Search results for "FeO"

showing 2 items of 82 documents

Sustainable Recycling of Insoluble Rust Waste for the Synthesis of Iron-Containing Perovskite-Type Catalysts

2019

Insoluble rust waste from the scraping of rusted iron-containing materials represents a cheap, eco-friendly, and available source of iron. LaFeO3 perovskite-type powders were successfully prepared by solution combustion synthesis using rust waste from an electricity transmission tower manufacturer. Solution combustion synthesis enabled introduction of this insoluble iron precursor directly into the final product, bypassing complex extraction procedures. Catalytic activity in the propylene oxidation of the waste-derived LaFeO3 with stoichiometric Fe/La ratio was almost identical to the commercial iron nitrate-derived LaFeO3 , thus demonstrating the viability of this recycling solution. The a…

rust wasteInsoluble rust waste LaFeO3 perovskite solution combustion synthesis propylene oxidationiron catalystsChemistryGeneral Chemical EngineeringFinal productExtraction (chemistry)General ChemistrySolution combustionRustArticleCatalysislcsh:ChemistryChemical engineeringlcsh:QD1-999Binary systemSettore CHIM/07 - Fondamenti Chimici Delle TecnologieStoichiometryPerovskite (structure)
researchProduct

The Radó–Kneser–Choquet theorem for $p$-harmonic mappings between Riemannian surfaces

2020

In the planar setting the Rad\'o-Kneser-Choquet theorem states that a harmonic map from the unit disk onto a Jordan domain bounded by a convex curve is a diffeomorphism provided that the boundary mapping is a homeomorphism. We prove the injectivity criterion of Rad\'o-Kneser-Choquet for $p$-harmonic mappings between Riemannian surfaces. In our proof of the injecticity criterion we approximate the $p$-harmonic map with auxiliary mappings that solve uniformly elliptic systems. We prove that each auxiliary mapping has a positive Jacobian by a homotopy argument. We keep the maps injective all the way through the homotopy with the help of the minimum principle for a certain subharmonic expressio…

subharmonicityPure mathematicsFUNCTIONALSMINIMIZERSGeneral Mathematicsp-harmonic mappings01 natural sciencesJacobin matriisitMathematics - Analysis of PDEsMaximum principleBOUNDARY-REGULARITYSYSTEMSMAPSRiemannian surface111 MathematicsFOS: MathematicsComplex Variables (math.CV)0101 mathematicsMathematicsCurvatureMathematics - Complex VariablesHomotopy010102 general mathematicsConvex curveHarmonic mapUnit diskHomeomorphismInjective functionEXISTENCEUNIQUENESSmaximum principlecurvature35J47 (Primary) 58E20 35J70 35J92 (Secondary)ELLIPTIC PROBLEMSDiffeomorphismJacobianunivalentAnalysis of PDEs (math.AP)Revista Matemática Iberoamericana
researchProduct