Strontium
Mostrando 1-12 de 194 artigos, teses e dissertações.
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1. Enhanced Catalytic Performance of Strontium-Doped Lanthanum Manganites by the Presence of Molybdenum Oxides for Electro-Reduction of Hydrogen Peroxide
In this work, two catalysts, lanthanum manganite strontium-doped perovskite without (LSM) and with (LSMMO) mixed molybdenum oxides, were synthesized by the sol-gel route and deposited by immersion in carbon cloth substrates. Their performance as cathodes in the hydrogen peroxide reduction reaction (HPRR) and oxygen reduction reaction (ORR) was investigated t
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. DETERMINATION OF TOTAL AND BIOACCESSIBLE ELEMENTS IN TEMPORARY ADHESIVE TATTOOS USED BY CHILDREN AND ADULTS
The presence of bioaccessible potentially-toxic elements in five different brands of temporary tattoos (packaged with bubble gums) aimed at children and three product brands used by young and adult audiences were analyzed in accordance with the Brazilian Organization of Technical Standards (ABNT) and International Organization for Standardization (ISO) for t
Química Nova. Publicado em: 2022
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3. ANODES FOR SOFC: REVIEW OF MATERIAL SELECTION, INTERFACE AND ELECTROCHEMICAL PHENOMENA
This paper presents a comprehensive interface and electrochemical phenomena review of different anodes for SOFC. In this way, it was possible to select some mixed electronic and ionic conductor materials alternatives to the conventional anode, Ni-YSZ conductor. New materials must present a satisfactory electronic and ionic conductivity at intermediate temper
Quím. Nova. Publicado em: 2021-01
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4. Strontium Oxide Decorated Iron Oxide Activated Carbon Nanocomposite: A New Adsorbent for Removal of Nitrate from Well Water
In the present study, activated carbon was magnetized by iron oxide and modified by strontium based nanoparticles (FeAC@Sr) to introduce it as an efficient favorable adsorbent for the removal of nitrate ions from underground water. The decorated adsorbent was characterized in terms of size, structure, morphology and composition using scanning electron micros
J. Braz. Chem. Soc.. Publicado em: 2020-01
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5. Preparation and characterization of yttria stabilized zirconia (YSZ) films deposited by dip-coating on LSM-YSZ substrate with different proportions
ABSTRACT In this work, sol-gel/dip-coating process for obtaining yttria stabilized zirconia (YSZ, ZrO2–8% Y2O3) films deposited onto LSM-YSZ (lanthanum strontium manganite (LSM, La0.7Sr0.3MnO3) mixed with YSZ) with different proportions (20/80, 50/50, 80/20) was investigated. The films were deposited on substrate varying the number of layers deposited. LSM
Matéria (Rio J.). Publicado em: 25/11/2019
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6. Magnetic Materials Enriched with Strontium: a Study of the use as Catalysts in the Transesterification Reaction of Babassu Oil
This work described a new magnetic material enriched with strontium as catalyst to produce babassu biodiesel. The use of magnetic materials has attracted attention due to easy and fast separation from reaction medium. Moreover, they are ecologically correct, due to they generate less discards to the environment. Techniques of analysis and characterization we
Mat. Res.. Publicado em: 30/09/2019
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7. Elemental Concentration and Sulfur Chemical Speciation in the Amazonian Plant Andira surinamensis Using Synchrotron Radiation Techniques (SR-XRF, XANES), RBS and WD-XRF
The inorganic composition of the bark and leaf of a plant from the Amazon rainforest, Andira surinamensis, was determined using two non-destructive, multi-element techniques: X-ray fluorescence (XRF) and Rutherford backscattering spectrometry (RBS). XRF measurements were made using both a conventional X-ray source and synchrotron radiation. It was observed t
J. Braz. Chem. Soc.. Publicado em: 16/09/2019
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8. Influence of Yttria-Stabilized Zirconia on Microstructure and Electrical Properties of Doped Lanthanum Gallate
Lanthanum gallate with partial substitutions for strontium and magnesium shows higher ionic conductivity than traditional ionic conductors such as yttria-stabilized zirconia (8YSZ), and has been considered for application as solid electrolyte and electrode in Solid Oxide Fuel Cells operating at intermediate temperatures (500-700ºC). Parallel to the developm
Mat. Res.. Publicado em: 01/08/2019
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9. Y3+ substituted Sr-hexaferrites: sol-gel synthesis, structural, magnetic and electrical characterization
Resumo Hexaferritas de estrôncio com adição de Y3+ com composição química SrYxFe12-xO19 (x= 0,0, 0,5, 1,0, 1,5) foram sintetizadas com sucesso pelo método sol-gel com autocombustão. Os estudos estruturais e morfológicos das amostras preparadas foram investigados usando a técnica de difração de raios X, espectroscopia de energia dispersiva, micros
Cerâmica. Publicado em: 06/06/2019
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10. Chemical characterization of archaeological pottery of the Lower Paraná River
Resumo Este artigo analisou a composição mineralógica da cerâmica arqueológica produzida por populações de caçadores-coletores e horticultores do Holoceno tardio na parte baixa da bacia do Paraná. Para analisar a composição química dos fragmentos foi utilizado um espectrômetro de fluorescência de raios X de energia dispersiva. Os resultados obt
Cerâmica. Publicado em: 06/06/2019
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11. Gold Supported on Strontium Surface-Enriched CoFe2O4 Nanoparticles: a Strategy for the Selective Oxidation of Benzyl Alcohol
The synthesis of efficient and reusable gold-based catalysts for the selective oxidation of alcohols is a strategy for the development of green processes. Pre-formed nanoparticles syntheses are an easy way to produce controlled-nanosized gold materials; however, the selection of a support is not trivial. Herein, we proposed a CoFe2O4 support enriched with Sr
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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12. Minerals multi-element analysis and its relationship with geographical origin of artisanal Mexican goat cheeses
Abstract The objective of this study was to perform a profile of mineral elements and the relationship of those as markers of geographical origin of artisanal goat cheese from the State of Veracruz, Mexico. In fresh and mature goat cheeses the quantified elements were: heavy (aluminum, arsenic, cadmium, lead), major (calcium, potassium, sodium, magnesium), e
Food Sci. Technol. Publicado em: 09/05/2019