Lanthanum
Mostrando 1-12 de 149 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. 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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3. 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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4. 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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5. Phosphate Adsorption by Montmorillonites Modified with Lanthanum/Iron and a Laboratory Test using Water from the Jacarepaguá Lagoon (RJ, Brazil)
Montmorillonites modified with lanthanum(III) and iron(III) were prepared from two commercial clays. These materials were characterized by powder X-ray diffraction analysis, X-ray fluorescence, infrared spectroscopy, N2 adsorption, and scanning electron microscopy. The incorporation of lanthanum(III) and iron(III) varied from 0 to 4.00%. The amount of these
J. Braz. Chem. Soc.. Publicado em: 2019-03
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6. Síntesis y caracterización de “tanatos” de lantano como inhibidores de la corrosión
ABSTRACT Tannins are polyphenols synthesized by plants. They are found in Quebracho (Schinopsis Balansae) wood, Tara (Caesalpinia spinosa) fruits, etc. They have been incorporated in the coating industry as "antifouling" agents and as corrosion inhibitors in acidic solutions. Moreover, lanthanum solutions have a great inhibitory effect over SAE 1010 steel co
Matéria (Rio J.). Publicado em: 19/07/2018
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7. Optimization of spin-coated electrodes for electrolyte-supported solid oxide fuel cells
ABSTRACT Electrodes for electrolyte-supported solid oxide fuel cells (SOFC's) were fabricated by spin coating. Strontium-doped lanthanum manganite (LSM) cathode and nickel yttria-stabilized zirconia cermet anodes were synthesized and processed for enhanced deposition conditions. The influence of electrode microstructural parameters was investigated by a syst
Matéria (Rio J.). Publicado em: 22/05/2017
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8. Effect of La 0.8 Sr 0.2 MnO 3 powder addition in the precursor solution on the properties of cathode films deposited by spray pyrolysis
ABSTRACT Films of lanthanum strontium manganite, LSM (La0.8Sr0.2MnO3) were deposited on yttria stabilized zirconia (YSZ) substrates by different methods aiming to establish the most suitable route to prepare cathodes for solid oxide fuel cells (SOFC). Samples were obtained by using a solution of lanthanum, strontium and manganese nitrates or a dispersion of
Matéria (Rio J.). Publicado em: 11/05/2017
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9. A study on the microstructural parameters of Zn (1-x)LaxZrxO nanopowders by X-ray line broadening analysis
In the present study, the pure and La-Zr co-doped ZnO nanoparticles were prepared by sol–gel technique using zinc acetate dehydrate (Zn(Ac)2·2H2O), lanthanum nitrate hexahydrate (La(NO3)3 ·6H2O) and zirconium chloride (ZrCl4) as precursor. The structure and morphology of the prepared nanoparticle samples were studied using X-ray diffraction and transmiss
Mat. Res.. Publicado em: 08/04/2016
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10. Preparation and characterization of a homemade Josephson junction prepared from a thin film sintered in a domestic microwave oven
A homemade Josephson junction was successfully obtained using a superconductor thin film of the BSCCO system. The film was deposited on a lanthanum aluminate, produced from a commercial powder with a nominal composition Bi1.8Pb0.4Sr2CaCu2Ox, was thermally treated by a domestic microwave oven. The XRD analysis of the film indicated the coexistence of Bi-2212
Mat. Res.. Publicado em: 08/03/2016
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11. Método hidrometalúrgico para reciclagem de metais terras raras, cobalto, níquel, ferro e manganês de eletrodos negativos de baterias exauridas de Ni-MH de telefone celular
A hydrometallurgical method for the recovery of rare earth metals, cobalt, nickel, iron, and manganese from the negative electrodes of spent Ni - MH mobile phone batteries was developed. The rare earth compounds were obtained by chemical precipitation at pH 1.5, with sodium cerium sulfate (NaCe(SO4)2.H2O) and lanthanum sulfate (La2(SO4)3.H2O) as the major re
Quím. Nova. Publicado em: 2014
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12. Study of the effects of lanthanum and the iron ion on the acidic properties of Al-pillared vermiculite
The synthesis of porous materials has attracted interest for decades due to their applications in catalysis and gas adsorption. Clay obtained by insertion of mesoporous oligomer [La xAl13-xO4 (OH)24 (H2O)12]7 + (where x equals the molar amount of lanthanum), followed by calcination, may cause variation in the acidic properties. The analyzes showed that incre
Mat. Res.. Publicado em: 05/07/2013