Electrochemistry
Mostrando 1-12 de 123 artigos, teses e dissertações.
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1. Dificuldades de ingressantes de um curso de licenciatura em química sobre conceitos da eletroquímica: um desafio para o ensino superior
The present work discusses some of the difficulties that chemistry undergraduates have with electrochemistry and possible impacts on higher education. They responded to a questionnaire about their insights and experiences regarding electrochemistry teaching, as well as their knowledge about it. The responses were categorized according to their difficulties,
Quím. Nova. Publicado em: 2021-06
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2. Electrochemical Behavior of Unusual Dimeric Flavonoids Isolated from Fridericia platyphylla
Brazil has the greatest plant diversity on the planet, distributed in different types of biomes. These plants are important sources of biologically active natural products, which are derived from various drugs marketed worldwide. This paper presents an electrochemical study of three unusual dimeric flavonoids, pharmacologically active, isolated and identifie
J. Braz. Chem. Soc.. Publicado em: 2021-06
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3. EFEITO DO HG2+ E DOS ÍONS CU2+, FE2+, NI2+, SN2+ E ZN2+ NA ESTABILIDADE DE NANOPARTÍCULAS DE PRATA: UMA PRÁTICA INTERDISCIPLINAR DE NANOTECNOLOGIA EXPERIMENTAL
The growing predominance of nanoscience and nanotechnology makes it increasingly important that these topics become an integral part of all scientific education. For this reason, in the present work, an interdisciplinary experiment of nanotechnology is introduced. As silver nanoparticles (AgNPs) are the most applied nanomaterial in consumer products, the cur
Quím. Nova. Publicado em: 2021-04
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4. LEARNING ABOUT EDGE EFFECTS AND ULTRAMICROELECTRODES IN ELECTROCHEMISTRY: SYNERGY BETWEEN EXPERIMENTS AND SIMULATIONS
A short experimental activity aimed at upper level undergraduate students or beginner researchers is presented to introduce the concepts of edge effects and hemispherical diffusion at ultramicroelectrodes. Students will perform simple cyclic voltammetry experiments varying the scan rate and using disk electrodes with different radii. They are then asked to i
Quím. Nova. Publicado em: 2020-09
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5. Medicinal Electrochemistry of Halogenated and Nitrated Pterocarpanquinones
Electrochemical methods are considered useful tools for simulations of biological redox reactions. The activities of quinones depend on their bioreduction. Biologically active pterocarpanquinones LQB-149 (nitroderivative), 150 and 151 (bromo and chloroderivatives, respectively) were electrochemically investigated by cyclic voltammetry, differential pulse vol
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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6. Antimicrobial Effects of Silver(I) and Bismuth(III) Complexes with Secnidazole-Derived Schiff Base Ligands: the Role of the Nitro Group Reduction
[Ag(HL)NO3] complexes (1-4) were obtained with (E)-N’-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)acetohydrazide (HL1); (E)-N’-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)benzohydrazide (HL2); (E)-2-(1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-ylidene)hydrazinecarbothioamide (HL3) and (E)-N-methyl-2-(1-(2-methyl-5-nitro-1H-imidazo
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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7. Nanoparticles of Fe2O3 and Co3O4 as Efficient Electrocatalysts for Oxygen Reduction Reaction in Acid Medium
This paper presents a comparative study about the oxygen reduction reaction (ORR) catalyzed by nanoparticles of Fe2O3 and Co3O4 applied on the surface of glassy carbon electrodes (GCE). The nanoparticles were synthesized using the modified polymeric precursor method (Pechini). These two nanomaterials were characterized by Fourier transform infrared spectrosc
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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8. MAGNETOMETRIA IN-SITU PARA CARACTERIZAÇÃO DE MATERIAIS ELETRODEPOSITADOS
We have recently made studies of electrodeposits of Co onto graphene attached to different substrates, successfully performed via in-situ magnetization measurements. The magnetic analysis of deposits as a function of time lapse, indicate that Co grows with different magnetic characteristics from the beginning to the end of each run, independent of the substr
Quím. Nova. Publicado em: 18/07/2019
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9. EFFECT OF THE NATURE OF THE ELECTROLYTE AND THE NATURE OF THE INTERFACE ON THE HYDROGEN EVOLUTION POTENTIAL: EXPERIMENTS FOR CHEMISTRY STUDENTS
This work presents an experiment done for chemistry students about the effect of the nature of the electrolyte and the nature of the interface on the hydrogen evolution reaction by electrolysis. Two techniques are suggested: method A - two identical copper electrodes in a direct current circuit and method B - three different electrodes in a dc potentiostatic
Quím. Nova. Publicado em: 27/05/2019
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10. Reduction Potential of RuIII-Based Complexes with Potential Antitumor Activity and Thermodynamics of their Hydrolysis Reactions and Interactions with Possible Biological Targets: a Theoretical Investigation
In this article density functional theory (DFT)-based calculations were employed to investigate the electrochemistry of the antitumor ruthenium complexes trans-tetrachloro(dimethylsulfoxide)imidazole ruthenate(III) (NAMI-A) and trans-[tetrachlorobis(1.-indazole)ruthenate(III)] (KP1019), their hydrolysis products as well as their interactions with biological
J. Braz. Chem. Soc.. Publicado em: 2019-03
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11. IMOBILIZAÇÃO DE COMPLEXO DE RUTÊNIO CONTENDO BASE DE SCHIFF NA UNIDADE METALOORGÂNICA UiO-67
Zirconium-based metal-organic framework, UiO-67, was synthesized and used as support for the immobilization of the [RuCl2(ENAPY)] (ENAPY = N,N'-bis(7-metyl-2-pyridylmethylene)-1,2-diiminoethane)). The immobilized system exhibited violet-blue color. The {UiO-67/[RuCl2(ENAPY)]} was characterized by cyclic voltammetry, X-ray diffraction, UV-Vis, FTIR and X-ray
Quím. Nova. Publicado em: 2018-07
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12. Advances in enzyme bioelectrochemistry
ABSTRACT Bioelectrochemistry can be defined as a branch of Chemical Science concerned with electron-proton transfer and transport involving biomolecules, as well as electrode reactions of redox enzymes. The bioelectrochemical reactions and system have direct impact in biotechnological development, in medical devices designing, in the behavior of DNA-protein
An. Acad. Bras. Ciênc.. Publicado em: 2018