scholarly journals An EPR Investigation of Defect Structure and Electron Transfer Mechanism in Mixed-Conductive LiBO2-V2O5 Glasses

2021 ◽  
Author(s):  
Jacob N. Spencer ◽  
Andrea Folli ◽  
Hong Ren ◽  
Damien M. Murphy
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Electron Transfer ◽  
Epr Spectroscopy ◽  
Defect Structure ◽  
Continuous Wave ◽  
Transfer Mechanism ◽  
Paramagnetic Resonance ◽  
Electron Transfer Mechanism ◽  
Electron Paramagnetic

Continuous Wave (CW) Electron Paramagnetic Resonance (EPR) spectroscopy was used to study the defect structure and electron transfer mechanism in a series of LiBO2-V2O5 mixed conductive glasses of varying V2O5...

Operando Electron Paramagnetic Resonance for Elucidating the Electron Transfer Mechanism of Coenzymes

2019 ◽  
Vol 123 (26) ◽  
pp. 16058-16064
Author(s):  
Mian A. Ali ◽  
Ayaz Hassan ◽  
Graziela C. Sedenho ◽  
Renato V. Gonçalves ◽  
Daniel R. Cardoso ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Electron Transfer ◽  
Transfer Mechanism ◽  
Paramagnetic Resonance ◽  
Electron Transfer Mechanism ◽  
Electron Paramagnetic

FORMATION OF $({\rm Ti}'_{\rm Ti} - V_{\rm O}^{\bullet \bullet})^{\bullet}$ DEFECT DIPOLES IN BaTiO3 CERAMICS HEAT-TREATED UNDER REDUCED OXYGEN PARTIAL-PRESSURE

2010 ◽  
Vol 03 (01) ◽  
pp. 65-68 ◽  
Author(s):  
EMRE ERDEM ◽  
PETER JAKES ◽  
RÜDIGER-A. EICHEL ◽  
DEREK C. SINCLAIR ◽  
MAHABOOB PASHA ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Barium Titanate ◽  
Oxygen Partial Pressure ◽  
Epr Spectroscopy ◽  
Defect Structure ◽  
Relative Size ◽  
Paramagnetic Resonance ◽  
Local Distortion ◽  
Heat Treated ◽  
Electron Paramagnetic

The defect structure of barium titanate ( BaTiO 3) heat-treated under reduced p O 2 has been investigated by electron paramagnetic resonance (EPR) spectroscopy. The results confirm the formation of [Formula: see text]-centers. Based on the relative size of the principal values of the electron g-matrix, g⊥ > g‖, the local distortion of the oxygen octahedron about the [Formula: see text]-centers was also analyzed and the formation of [Formula: see text] defect associates unambiguously established.

Investigation of Antioxidant Activity of Pomegranate Juices by Means of Electron Paramagnetic Resonance and UV-Vis Spectroscopy

2015 ◽  
Vol 98 (4) ◽  
pp. 866-870 ◽  
Author(s):  
Violetta Kozik ◽  
Krystyna Jarzembek ◽  
Agnieszka Jędrzejowska ◽  
Andrzej Bąk ◽  
Justyna Polak ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance ◽  
Free Radical ◽  
Epr Spectroscopy ◽  
Antioxidant Properties ◽  
Free Radical Scavenger ◽  
Pomegranate Juice ◽  
Radical Scavenger ◽  
Paramagnetic Resonance ◽  
Vis Spectroscopy ◽  
Electron Paramagnetic

Abstract Pomegranate fruit (Punica granatum L.) is a source of numerous phenolic compounds, and it contains flavonoids such as anthocyanins, anthocyanidins, cyanidins, catechins and other complexes of flavonoids, ellagitannins, and hydrolyzed tannins. Pomegranate juice shows antioxidant, antiproliferative, and anti-atherosclerotic properties. The antioxidant capacity (TEAC) of the pomegranate juices was measured using electron paramagnetic resonance (EPR) spectroscopy and 1,1-diphenyl-2-picrylhydrazyl (DPPH•) as a source of free radicals, and the total phenolic (TP) content was measured using UV-Vis spectroscopy. All the examined pomegranate juices exhibited relatively high antioxidant properties. The TEAC values determined by means of EPR spectroscopy using Trolox (TE) as a free radical scavenger were in the range of 463.12 to 1911.91 μmol TE/100 mL juice. The TP content measured by the Folin-Ciocalteu method, using gallic acid (GA) as a free radical scavenger, widely varied in the investigated pomegranate juice samples and ranged from 1673.62 to 5263.87 mg GA/1 L juice. The strongest antioxidant properties were observed with the fresh pomegranate juices obtained from the fruits originating from Israel, Lebanon, and Azerbaijan. Correlation analysis of numerical data obtained by means of EPR spectroscopy (TEAC) and UV-Vis spectroscopy (TP) gave correlation coefficient (r) = 0.90 and determination coefficient (r2) = 0.81 (P <0.05).

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