Exact and Earth Sciences: Recent Submissions
Now showing items 461-470 of 6389
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Spectroscopic insights into the role of CO2 on the nature of Cr species in a CrOX/Al2O3 catalysts during ethane dehydrogenation with CO2
(2023) [Journal article]The dehydrogenation of ethane with CO2 was studied on CrOx/Al2O3 catalysts (8 wt% of CrOx) in the 600–675 °C temperature range. The role of CO2 was determined by comparison with catalytic and spectroscopic data of ethane ... -
First report of chemical composition and cytotoxicity evaluation of Foraminispora rugosa basidiomata from Brazil
(2022) [Journal article]Foraminispora rugosa is a species reported from Brazil, Venezuela, French Guiana, Costa Rica and Cuba. It is a basidiomycete in the Ganodermataceae family. In this study, both chemical composition and cytotoxicity of the ... -
Estimativa da taxa de erosão sedimentar da geleira Wanda (Shetlands do Sul) com o uso de modelo numérico
(2012) [Journal article]A produção sedimentar glacial resulta da erosão glacial e é influenciada por vários fatores incluindo o grau de retração glacial, velocidade do fluxo de gelo e o regime termal. Este artigo estima o grau de erosão atual e ... -
Dinâmica glacial e características sedimentares da zona proglacial da Geleira Ecolology - Baía do Almirantado, Ilha Rei George - Antártica
(2006) [Journal article]A geleira Ecology, localizada na ilha Rei George, ilhas Shetlands do Sul, está sofrendo um processo de rápida retração ao longo das últimas décadas, sendo que no período de 1956 a 1992/95 a geleira retrocedeu 0,37 km². ... -
Compilation of geomorphological map for reconstructing the deglaciation of ice-free areas in the Martel intlet, King George island, Antarctica
(2013) [Journal article]We compiled a geomorphological map and a reconstruction map of glacier extension and ice-free areas in the Martel Inlet, located in King George Island, South Shetlands, Antarctica. Glacier extension data were derived from ... -
Efeitos do sistema Keller sobre o estudante
(1979) [Journal article]Em um curso de Física Geral, na UFRGS, são comparados dois grupos, em egresso do sistema de ensino tradicional e outro do sistema Keller, quando ambos são submetidos a cada um dos métodos Keller e Audiotutorial. Os sistemas ... -
Volatile profile of sparkling wines produced with the addition of mannoproteins or lees before second fermentation performed with free and immobilized yeasts
(2018) [Journal article]Heat map and hierarchical cluster analysis showed that sparkling wines produced with immobilized yeasts contained mostly higher levels of compounds that impart positive notes to wines. Fisher ratio pointed out nine volatile ... -
Method development and total uncertainty estimation for boron, sulfur and phosphorus determination in mineral fertilizer using ICP OES
(2016) [Journal article]This study deals with B, S, and P determination in mineral fertilizer and S in commercial sulfur-formulation using inductively coupled plasma optical emission spectrometry. According to multivariate optimization using a ... -
Computational study of electronic effects from β-substituents on the tautomerism of naphthazarin derivatives
(2017) [Journal article]In this work, semi-empirical AM1 and DFT B3LYP/6-31G** calculations were applied in the study of the interconversion among tautomers of several naphthazarin and 5-amino-8-hydroxy-1,4-naphthoquinone β-substituted derivatives ... -
Relações não lineares na curva de Phillips : uma abordagem semi-paramétrica
(2015) [Journal article]A relação entre inflação e atividade econômica é um dos principais interesses dos macroeconomistas. Geralmente, o trade-off entre inflação e produto é considerado linear. Mas isso é correto? Caso não seja, qual é a forma ...