Mossbauer
Mostrando 13-24 de 293 artigos, teses e dissertações.
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13. Structural, Morphological and Magnetic Properties of FeCo-(Fe,Co)3O4 Nanocomposite Synthesized by Proteic Sol-Gel Method Using a Rotary Oven
FeCo nanoparticles coated with (Fe,Co)3O4 (magnetite doped with cobalt) were synthesized by the proteic sol-gel chemical route. The synthesized materials were characterized by Thermogravimetry (TG), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), vibrating-sample magnetometer (VSM) and Mössbauer spectrosc
Mat. Res.. Publicado em: 18/03/2019
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14. Controlled Dehydration of Fe(OH)3 to Fe2O3: Developing Mesopores with Complexing Iron Species for the Adsorption of β-Lactam Antibiotics
In this work, efficient adsorbents for β-lactam antibiotics based on mesoporous iron oxide containing surface [FeOx(OH)y] sites were produced by controlled precipitation of iron hydroxide and thermal treatment at 150, 200, 300 and 450 ºC (150FeOH, 200FeOH, 300FeOH and 450FeOH, respectively). Mössbauer, X-ray diffraction (XRD), thermogravimetry-mass spectr
J. Braz. Chem. Soc.. Publicado em: 2019-02
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15. The Structural and the Magnetic Properties of Aluminum Substituted Yttrium Iron Garnet
In this paper, Y3AlxFe5-xO12 powders with x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0 were prepared via solid state reaction method. X-ray diffraction, Vibrating Sample Magnetometry, and Mössbauer Spectroscopy were used to study their structural and magnetic properties. The XRD patterns of the samples show single phase structure with decreasing lattice constant wh
Mat. Res.. Publicado em: 15/03/2018
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16. Physical and chemical study of lattice kaolinites and their interaction with orthophosphate
ABSTRACT This study covers the evaluation of the structure and the capacity in adsorbing orthophosphate ions of kaolinites collected from sampling sites in Manaus (Brazil). The kaolinites were obtained using physical fractioning (sieving/siphoning) techniques and chemical treatment with HCl, H2SO4, H2O2 and KCl. The investigation of the kaolinite lattices in
An. Acad. Bras. Ciênc.. Publicado em: 2017-09
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17. Structure and Physical Properties of the LaBiFe2O6 Perovskite Produced by the Modified Pechini Method
In this paper the synthesis of the LaBiFe2O6 material by the modified Pechini method is reported. Structural, morphologic, magnetic and optic experimental studies were performed. Rietveld refinement of x-ray diffraction patterns revealed that LaBiFe2O6 crystallizes in an orthorhombic perovskite structure (space group Pnma, # 62). Scanning electron microscopy
Mat. Res.. Publicado em: 24/07/2017
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18. Chemical-Mineralogical Characterization of Magnetic Materials from Magnetic Soils of the Southern Espinhaço Mountain Chain and of the Upper Jequitinhonha Valley, State of Minas Gerais, Brazil
ABSTRACT In the Southern Espinhaço Mountain Chain and in the Upper Jequitinhonha Valley, magnetic soils, in different pedogenetic stages, are found to be forming over intrusions of basic lithology. The essential chemical and mineralogical properties of samples from magnetic soil profiles from those two physiographic environments in the state of Minas Gerais
Rev. Bras. Ciênc. Solo. Publicado em: 27/03/2017
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19. A Mesoporous SiO2/γ-Fe2O3/KI Heterogeneous Magnetic Catalyst for the Green Synthesis of Biodiesel
A magnetic catalyst (sample MCat) consisting of KI supported on a mixture of silica and maghemite (γ-Fe2O3) was prepared and used in the transesterification reaction for the synthesis of biodiesel. The energy dispersive X-ray spectrum of the catalyst showed signals due to Si, Fe, K, and I. Powder X-ray diffraction data revealed the amorphous nature of the S
J. Braz. Chem. Soc.. Publicado em: 2016-12
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20. SÍNTESE E CARACTERIZAÇÃO DE NOVOS ORGANOMETÁLICOS DE ESTANHO (IV) COM LIGANTES DITIOCARBIMATOS E SUA AÇÃO ACCELERADORA NA VULCANIZAÇÃO DE BORRACHA NITRÍLICA
This paper describes the synthesis of four new organotin compounds of general formula: (Ph4P)[Sn(Cy)3(RSO2N=CS2)] [Ph4P = tetraphenylphosphonium cation, Cy = cyclohexyl, R = C6H5 (1), 4-ClC6H4 (2), 4-BrC6H4 (3) and 4-IC6H4 (4)]. They were obtained by the reaction between four different potassium N-R-sulfonyldithiocarbimate salts and tricyclohexyltin chloride
Quím. Nova. Publicado em: 2016-08
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21. SAIS DE TETRAFENILFOSFÔNIO E TRIS(1,10-FENANTROLINA)FERRO(II) DE COMPLEXOS ANIÔNICOS DE DIBUTILESTANHO(IV) COM DITIOCARBIMATOS: SÍNTESE, CARACTERIZAÇÃO E ATIVIDADE ANTIFÚNGICA
Six new salts of organometallic complexes of tin(IV) with the general formulae: (Ph4P)2[Sn(Bu)2(RSO2N=CS2)2] and [Fe(phen)3][Sn(Bu)2(RSO2N=CS2)2] [Ph4P = tetraphenylphosphonium, R = CH3 (1), C2H5 (2) and C4H9 (3); Fe(phen)3 = tris(1,10-phenanthroline)iron(II), R = CH3 (4), C2H5 (5) and C4H9 (6)] were synthetized from potassium dithiocarbimates (RSO2N=CS2K2.H
Quím. Nova. Publicado em: 2016-06
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22. Cellulose Nanocrystals Assembled on the Fe3O4Surface as Precursor to Prepare Interfaced C/Fe3O4Composites for the Oxidation of Aqueous Sulfide
In this work, composites based on carbon (1, 10 and 20 wt.%) interfaced with Fe3O4 (magnetite) have been studied as catalysts for the oxidation of aqueous sulfide. The composites were prepared by assembling cellulose nanocrystals surrounding Fe3O4 followed by a controlled thermal decomposition at 400, 600 and 800 ºC. Mössbauer, X-ray diffractometry (XRD),
J. Braz. Chem. Soc.. Publicado em: 2016-02
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23. Use of Biodiesel Press Cake Waste to Prepare Fe/Carbon Reactive Composites for Environmental Applications: Removal of Hazardous CrVI Contaminants
In this work, Ricinus communis L. press cake waste from biodiesel production was used to produce a versatile reactive material for environmental applications. The biodiesel cake waste was impregnated with FeIII at different concentrations (19-45 wt.%) and treated at 400, 600 and 800 °C. Mössbauer, X-ray diffraction (XRD), thermogravimetric analysis (TG/DTA
J. Braz. Chem. Soc.. Publicado em: 2015-10
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24. Microesferas magnéticas à base de poli(metacrilato de metila-co-divinilbenzeno) obtidas por polimerização em suspensão
Microesferas poliméricas à base de metacrilato de metila (MMA), divinilbenzeno (DVB) e material magnético foram preparadas via polimerização por suspensão. Foi estudada a influência da polimerização em suspensão ou semisuspensão, concentração de material magnético e concentração de divinilbenzeno sobre as características das microesferas obt
Polímeros. Publicado em: 2015-04