Chemical Signature
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Encoding of Luminescent Ink Markers Using Low-Level Data Fusion and Chemometrics
The identification and analysis of documentary fraud is always a challenge for forensic science. Document analysis has proven to be an important branch of forensics in elucidating the authenticity of documents. The development and incorporation of luminescent inks in authentic documents have proved to be an excellent security feature. This paper purposes the
Journal of the Brazilian Chemical Society. Publicado em: 2023
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2. Provenance of the Ediacaran Salinas Formation (Araçuaí Orogen, Brazil): Clues from lithochemical data and zircon U-Pb (SHRIMP) ages of volcanic clasts
Abstract Salinas Formation occurs in a large region of the Northern Araçuaí orogen, Southeastern Brazil. It includes turbiditic wackes (> 10% matrix) to arenites (< 10% matrix), pelites and clast-supported conglomerates, metamorphosed from the biotite zone of the greenschist facies to the sillimanite zone of the amphibolite facies. Salinas Formation lies u
Braz. J. Geol.. Publicado em: 01/07/2019
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3. Geochemistry and Spatial Variability of Rare Earth Elements in Soils under Different Geological and Climate Patterns of the Brazilian Northeast
ABSTRACT Growth in the agricultural and industrial sectors has increased the demand for rare earth elements (REEs) in the production of technological devices and fertilizers. Thus, the accumulation of these elements in the soil has become an environmental concern. Here, we aim to determine the natural contents of REEs in soils derived from different parent m
Rev. Bras. Ciênc. Solo. Publicado em: 02/07/2018
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4. Geochemical Signature of Amazon Tropical Rainforest Soils
ABSTRACT: Evaluating soil geochemical diversity in the Amazon Basin has been a challenge largely because most study sites have been at the edge of the basin and it is difficult to get samples in such a region. Here we show that even among the most weathered soils, physicochemical soil properties express lithology. Our results are based on topsoil samples col
Rev. Bras. Ciênc. Solo. Publicado em: 15/02/2018
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5. Characterization of CBD-CdS Doped with Some Rare Earths III (Eu3+,Ce3+) as Function of Synthesis Time
Rare earths (Europium, cerium)-doped CdS nanofilms are prepared using the growth technique chemical bath deposition (CBD) at the reservoir temperature of 70±2°C varying the synthesis time in a wide range. For the rare earths doped CdS nanofilms the synthesis time was ranged from 80 to 135 min. The rare earths molar concentration was in the range 0.0≤x≤
Mat. Res.. Publicado em: 01/02/2018
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6. Petrography, geochemistry and geochronology of the potassic granitoids of the Rio Itacambiruçu Supersuite: implications for the Meso- to Neoarchean evolution of the Itacambira-Monte Azul block
ABSTRACT: In the Itacambira-Monte Azul block (BIMA) the Archean rocks are represented by tonalite-trondhjemite-granodiorite (TTGs) of the Porteirinha Complex and by potassic granitoids of the Rio Itacambiruçu Suite that crop out at the Pedra do Urubu (PUp), Rio Gorutuba (RGp), Barrocão (BAp) and Lagoa Nova (LNp) plutons. This work presents new data for the
Braz. J. Geol.. Publicado em: 2018-01
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7. Chemical cuticular signature of leafcutter ant Atta sexdens (Hymenoptera, Formicidae) worker subcastes
ABSTRACT In leafcutter ants the division of labour is associated to worker size variation clustered in four subcastes. In this work we used Atta sexdens Forel (1908) as a model to test the hypothesis that each subcaste expresses its own chemical signature comprised of cuticular lipids. To assess it, we extracted epicuticular compounds by using nonpolar solve
Rev. Bras. entomol.. Publicado em: 2016-12
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8. Geoquímica e isótopos de Nd de rochas metavulcânicas da antiforme Capané, complexo metamórfico Porongos, RS
The Capané Antiform, located in the northern part of the Neoproterozoic Porongos Metamorphic Complex (RS), is composed of a supracrustal sequence metamorphosed under greenschist (eastern flank) to amphibolite (western flank) facies. Four groups of rocks were recognized. Groups 1 and 2 are constituted of felsic and mafic rocks from the central and western pa
Publicado em: 2010
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9. Mineralogia e petrologia de xenólitos mantélicos das regiões de Ubatuba (SP) e Monte Carmelo (MG): evidências de fusão parcial e metassomatismo no manto superior do sudeste do Brasil / Mineralogy and petrology of mantle xenoliths from Ubatuba (SP) and Monte Carmelo (MG): melting and metasomatism evidences in the upper mantle from southeast Brazil
Mineralogical and petrological studies were conducted in mantle xenoliths included in a kaersutite lamprophyre dyke from Ubatuba (SP) (Serra do Mar Igneous Province), and in the Limeira 1 Kimberlite (Monte Carmelo, MG; Alto Paranaíba Alkalic Province), using petrography and major and trace element geochemistry in minerals by electron microprobe and LA-ICPMS
Publicado em: 2009
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10. Petrogêneses do complexo vulcânico Yate (42, 30ºS), Andes do Sul, Chile / Petrogenesis of the Yate Volcanic Complex (42, 30ºS), Andes Southern, Chile
The Yate Volcanic Complex (CVY) is located in the Southern Volcanic Zone of the Chilean Andes, at 42°30S, comprising the Yate, Gualaihué and Hornopirén volcanoes. The Yate volcano is a major compound type in which effusive activity occurred since Upper Pleistocene (c. 122 ka) until Holocene. Hornopirén and Gualaihué are minor, and represent strombilian-
Publicado em: 2009
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11. Vulnerability of soil organic matter to temperature increase / Vulnerabilidade da matéria orgânica do solo ao aumento de temperatura
Soil organic matter (SOM) decomposition emits greenhouse gases to the atmosphere and this may contribute to global warming. Global warming can promote a positive feedback on SOM decomposition rate and it can increase soil C losses. The SOM has different pools with inherent temperature sensitivity. Some researches suggest that resistant soil C is less sensiti
Publicado em: 2008
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12. Classificação estrutural de famílias de proteínas com base em mas de contatos.
The objective of this work was to verify if it is possible to classify protein chain structures using only the chemical interactions between its residues. Through contact maps and using three different metrics based on image processing techniques we have showed that we are able to classify such structures in families of similar structure and function with pr
Publicado em: 2008