Feiii Complex
Mostrando 1-12 de 38 artigos, teses e dissertações.
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1. A Procedure for Assessment of the Reducing Capacity of Plants-Derived Beverages Based on the Formation of the FeII/2,2’-Bipyridine Complex
An alternative spectrophotometric ferric reducing activity power (FRAP) method for quantification of total reducing capacity (TRC) was developed. The method is based on the reduction of FeIII to FeII by antioxidant compounds containing 2,2’-bipyridine (bipy) in aqueous solution. Absorbance values recorded at 521 nm, characteristic of the Fe(bipy)32+ comple
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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2. Contribution of Irradiation and Dihydroxybenzenes on Iron(III) Reduction in Fenton Process
The contribution of irradiation and the dihydroxybenzenes (DHB), catechol (CAT) and hydroquinone (HQ), added or formed as phenol oxidation intermediates, was evaluated for the reduction of FeIII and for phenol degradation via Fenton processes. The formation of CAT and HQ was observed during phenol degradation starting with Fe2+ or Fe3+ in the presence or abs
J. Braz. Chem. Soc.. Publicado em: 2016-06
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3. Degradation of organic pollutants and characteristics of activated sludge in an anaerobic/anoxic/oxic reactor treating chemical industrial wastewater
A laboratory-scale anaerobic/anoxic/oxic system operated at the hydraulic retention times (HRT) of 20, 40, and 60 h with mixed liquor suspended solids (MLSS) concentrations of 3 g/L and 6 g/L was considered for treating chemical industrial wastewater rich in complex organic compounds and total dissolved solids. Extending the HRT and increasing the MLSS conce
Braz. J. Chem. Eng.. Publicado em: 2014-09
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4. Preconcentration, determination and speciation of iron by solid-phase extraction using dimethyl (E)-2-[(Z)-1-acetyl)-2-hydroxy-1-propenyl]-2-butenedioate
A new sensitive and selective procedure for speciation of trace dissolved Fe(III) and Fe(II), using modified octadecyl silica membrane disks and determination by flame atomic absorption spectrometry was developed. A ML3 complex is formed between the ligand and Fe(III) responsible for extraction of metal ion on the disk. Various factors influencing the separa
Química Nova. Publicado em: 2012
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5. Zn-edta degradation by catechol-driven fenton reaction
Zn-EDTA degradabilty by catechol-driven Fenton reaction was studied. Response surface methodology central composite design was employed to maximize this complex degradation. Theoretical speciation calculations were in good agreement with the experimental results. Fenton and Fenton type treatments are typically thought to be applicable only in the highly acid
Quím. Nova. Publicado em: 2012
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6. Catalytic promiscuity: catecholase-like activity and hydrolytic DNA cleavage promoted by a mixed-valence FeIII FeII complex
Os estudos sobre enzimas têm mostrado que existe uma relação clara entre a evolução enzimática e a propriedade de promiscuidade catalítica que elas podem apresentar. Com isto, o desenvolvimento de sistemas biomiméticos capazes de atuar de modo promíscuo, de forma similar a algumas enzimas, mostrou-se um novo desafio para os químicos bioinorgânicos
Journal of the Brazilian Chemical Society. Publicado em: 2010
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7. DEVELOPMENT OF FLOW PROCEDURES INVOLVING SOLID-PHASE REACTOR AND ANALYTICAL MICROSYSTEM CONSTRUCTED WITH LTCC (LOW TEMPERATURE CO-FIRED CERAMICS) TO DETERMINATION OF ANALYTES OF PHARMACEUTICAL INTEREST / Desenvolvimento de procedimentos em fluxo envolvendo reatores em fase sólida e microssistema analítico construído com LTCC (Low Temperature Co-fired Ceramics) para a determinação de analitos de interesse farmacêutico
The employment of flow injection systems to determination of N-acetylcysteine, captopril, dipyrone and fluoxetine hydrochloride in pharmaceutical formulations was investigated. The N-acetylcysteine was determinated employing a solid-phase reactor containing Zn3(PO4)2 immobilized in a polyester resin coupled to a flow injection system. The procedure was based
Publicado em: 2009
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8. Mecanismos de ação de antioxidantes de origem vegetal : estudo do polifenol ácido elágico e do extrato de caqui (Diospyros kaki)
The present work was divided in 2 chapters. In the first chapter, we investigated the antioxidant mechanism of ellagic acid (EA) to prevent oxyradical formation in a system containing Cu(II) plus ascorbate. The antioxidant property of persimmon pulp in oxidative processes mediated by Fe(III) in vitro was studied in the second chapter. EA study demonstrated t
Publicado em: 2008
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9. COMPLEXOS METÁLICOS DE 2-PIRIDINOFORMAMIDA TIOSSEMICARBAZONAS: ESTUDOS EM SOLUÇÃO, NO ESTADO SÓLIDO E ATIVIDADE CITOTÓXICA / METAL COMPLEXES OF 2-PYRIDINEFORMAMIDE THIOSEMICARBAZONES: SOLUTION STUDIES, SOLID STATE STUDIES AND CYTOTOXIC ACTIVITY.
Thiosemicarbazones and their metal complexes present a wide range of bioactivities. It has been shown that the antitumoral action of á(N)-heterocyclic thiosemicarbazones occurs through the inhibition of ribonucleotide diphosphate reductase (RDR), a key enzyme involved in the conversion of ribonucleotides into deoxyribonucleotides during DNA syntheses. The a
Publicado em: 2008
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10. Extração dos íons Cu(II), Cd(II), Fe(III) e Zn(II) utilizando um sistema aquoso bifásico constituído pelo copolímero L35 e o sal Li2SO4 / Extraction of the ions Cu(II), Cd(II), Fe(III) and Zn(II) using aqueous biphasic system constituted by the copolymer L35 and the salt Li2SO4
In this work, the extraction behavior of the metal ions Cd (II), Cu(II), Fe(III) and Zn(II) has been separately investigated in aqueous biphasic systems (ABS) formed by the triblock copolymer (Pluronic L35,
= 1900.g.mol-1) and the salt Li2SO4, in the presence of extractant agents either soluble or insoluble in water. The extractant thiocyanate (SCN-), io Publicado em: 2007
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11. SÃntese, caracterizaÃÃo e estudo da liberaÃÃo fotoquÃmica de Ãxido nÃtrico por nitrosilo complexos de Ru e Fe e pelo composto [cyclam(NO)4]. / Synthesis, characterization and study of the release nitric oxide photochemistry complex for nitrosilo of Ru and Fe and for the composition [cyclam (IN) 4].
Neste trabalho à apresentada a sÃntese, caracterizaÃÃo e o estudo da liberaÃÃo fotoquÃmica de Ãxido nÃtrico pelos nitrosilo complexos trans-[Fe(cyclam)(NO+)Cl]Cl2 e trans-[Ru(NH3)4L(NO)]Cl3, onde L=Imidazol, Benzoimidazol, CafeÃna e Teofileno, bem como pelo novo composto [cyclam(NO)4]. AtravÃs de uma nova rota sintÃtica, obteve-se o composto tran
Publicado em: 2006
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12. Estudo da oxidação de pirita em meio alcalino através de modelagem termodinâmica e de análises por difração de raios-x, espectroscopia de infravermelho e raman
An investigation of pyrite oxidation in alkaline solutions by thermodynamic modeling and analyses by Xray diffraction, infrared and Raman spectroscopy was carried out. The effect of pH and solution composition on the nature of the oxide product and complex formation is explained. A mechanism is proposed to explain the increase of the oxidation rates in carbo
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 31/08/2005