Magnetic Metals
Mostrando 1-12 de 59 artigos, teses e dissertações.
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1. APRESENTAÇÃO - História Antiga: Diferentes Perspectivas
Biodiesel is a suitable alternative to replace the petro-diesel. The biodiesel is formed by unsaturated esters easily degraded by interferences of oxygen, temperature, contact with metals or contaminants. The aim of this research was to investigate the biodiesel degradation process via 1H nuclear magnetic resonance (NMR) spectroscopy, observing the olefinic,
Rev. Bras. Hist.. Publicado em: 2020-08
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2. Evaluation of the Oxidation Degradation Process of Biodiesel via 1H NMR Spectroscopy
Biodiesel is a suitable alternative to replace the petro-diesel. The biodiesel is formed by unsaturated esters easily degraded by interferences of oxygen, temperature, contact with metals or contaminants. The aim of this research was to investigate the biodiesel degradation process via 1H nuclear magnetic resonance (NMR) spectroscopy, observing the olefinic,
J. Braz. Chem. Soc.. Publicado em: 2020-08
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3. Combined Analytical Py-GC/MS, SEM, FTIR and 13C NMR for Investigating the Removal of Trace Metals from Aqueous Solutions by Biochar
In this study, the efficiency of biochar (BC) produced from sugarcane bagasse at different pyrolysis temperatures (300, 400, 500 and 600 ºC) for simultaneous removal of CdII, PbII, CuII, CrIII, NiII and ZnII ions from aqueous solutions was assessed. All BC were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), 13C nu
J. Braz. Chem. Soc.. Publicado em: 2020-07
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4. Análisis comparativo en la determinación de ferrita delta para aceros inoxidables austeníticos
ABSTRACT In the welding of austenitic stainless steels, the determination of delta ferrite (δ-ferrite) is very important to assess the susceptibility of weld metal to hot cracking, one of the major problems related to weldability, metallurgical and mechanical behavior of this type of steels. The determining δ-ferrite in the weld metal can be performed with
Matéria (Rio J.). Publicado em: 19/07/2018
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5. Operational conditions of an electrostatic separator for concentrate copper from electronic waste
Abstract Interest in recycling for the recovery of valuable substances, such as precious metals from electric and electronic waste has been increasing year after year due to the large amount present in such waste compared to primary sources. There is environmental concern, since the amount of this kind of waste is increasing due to rapid technological advanc
REM, Int. Eng. J.. Publicado em: 2018-07
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6. OS LANTANÍDEOS NAS REDES METALORGÂNICAS: UMA NOVA CLASSE DE MATERIAIS POROSOS
Lanthanoid organic frameworks (LOFs) stand out as an important class of functional materials. The possibility to employ a great range of metals and ligands lead to the formation of varied and highly porous structures, with diverse applications. The presence of lanthanoid ions favours the improvement of the optical, magnetic and redox properties of MOFs. This
Quím. Nova. Publicado em: 2018-06
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7. Green Processing of Strategic Elements Based on Magnetic Nanohydrometallurgy
Magnetic nanohydrometallurgy (NHM) is a new process based on engineered superparamagnetic nanoparticles capable of performing as complexing agents for extracting and recovering strategic metals from mineral sources and urban wastes, as well as for removing hazardous elements from contaminated water. Its principles and application are reviewed in this paper.
J. Braz. Chem. Soc.. Publicado em: 2018-05
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8. Cellulose Oxidation and the Use of Carboxyl Cellulose Metal Complexes in Heterogeneous Catalytic Systems to Promote Suzuki-Miyaura Coupling and C-O Bond Formation Reaction
This work shows the modification of microcrystalline cellulose by the selective oxidation of primary hydroxyl groups to carboxylate groups by a 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated system and its application as a heterogeneous ligand by ionic exchange with catalytic metals ions such as palladium, nickel and copper. Afterwards is desc
J. Braz. Chem. Soc.. Publicado em: 2017-11
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9. Electronic Effect of V, Ti, and Sc Impurities on the Hyperfine Interactions of Fe Atoms in α-Fe: A First Principles Study
The Linearized Augmented Plane Wave method, as implemented in the Wien2k computational code, was used to investigate the effects of the 3d transition metals (TM) Sc, Ti, and V impurities on the hyperfine interaction of iron atoms in α-Fe. The calculation results of this study suggest that the introduction of a TM (TM = Sc, Ti, and V) impurity into α-Fe inc
Mat. Res.. Publicado em: 02/03/2017
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10. MICROEMULSÕES: COMPONENTES, CARACTERÍSTICAS, POTENCIALIDADES EM QUÍMICA DE ALIMENTOS E OUTRAS APLICAÇÕES
Microemulsions (MEs) are thermodynamically stable systems consisting of nanosized droplets dispersed in a solvent continuous medium (known as pseudo-phase), which is immiscible with the dispersed phase. These systems consist of water, a hydrophobic solvent called "oil," an amphiphile and often, a co-surfactant that is normally a medium chain alcohol. A large
Quím. Nova. Publicado em: 2015-11
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11. Síntese e caracterização de nanopartículas Fe3O4@Au e desenvolvimento de sensores para aplicações em nanomedicina / Synthesis and characterization of Fe3O4@Au nanoparticles and development of sensors for application in nanomedicine
Along with the development of nanomaterials came the knowledge and design of their unique eletronic, optical and catalitycal properties which may be used for a variety of nanotecnological applications. A special class of nanomaterials with interesting characteristics is represented by the CoreαShell nanoparticles, which combine the physicochemical prop
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/07/2012
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12. Valores de referência para metais potencialmente tóxicos em sedimentos e em moluscos filtradores no Rio Ribeira de Iguape / Reference values to potentially toxic metals in sediments and mussels in the River Ribeira de Iguape
The Ribeira do Iguape River Basin (RIRB) was historically influenced by intense mining activities mainly related to lead (Pb) extraction. For many decades, such exploitation was conducted under rudimentary conditions without control of environmental impacts produced during the stages of ore extraction and beneficiation. Thus, mining wastes and metallurgical
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 20/06/2012