ChemInform Abstract: THE STANDARD OXIDATION POTENTIALS OF THE (II-III) AND (III-IV) REDOX SYSTEMS OF THE LANTHANIDES AND THE ACTINIDES IN NONAQUEOUS SOLVENTS

1978 ◽  
Vol 9 (3) ◽  
Author(s):  
G. DUYCKAERTS ◽  
B. GILBERT
Keyword(s):  
Nonaqueous Solvents ◽  
Redox Systems ◽  
Oxidation Potentials

Triarylamines on [3]Radialene Scaffold: Novel [3]Radialene-based, Multistep, Wide-range Redox Systems with Remarkably Low Oxidation Potentials

2011 ◽  
Vol 40 (9) ◽  
pp. 1033-1035 ◽  
Author(s):  
Kouzou Matsumoto ◽  
Nao Yamada ◽  
Tetsuya Enomoto ◽  
Hiroyuki Kurata ◽  
Takeshi Kawase ◽  
...  
Keyword(s):  
Redox Systems ◽  
Oxidation Potentials ◽  
Wide Range

Redox Systems, Antioxidants and Sarcopenia

2018 ◽  
Vol 19 (7) ◽  
pp. 643-648 ◽  
Author(s):  
Bertrand Fougère ◽  
Gabor Abellan van Kan ◽  
Bruno Vellas ◽  
Matteo Cesari
Keyword(s):  
Redox Systems

Polymerization of acrylonitrile initiated by peroxomonosulphate-thiols redox systems

1990 ◽  
Vol 55 (8) ◽  
pp. 2001-2007
Author(s):  
Gurusamy Manivannan ◽  
Pichai Maruthamuthu
Keyword(s):  
Ionic Strength ◽  
Thermodynamic Parameters ◽  
Thermal Polymerization ◽  
Reaction Scheme ◽  
Degree Of Polymerization ◽  
Reducing Agent ◽  
Redox Systems ◽  
Temperature Range ◽  
Rate Of Polymerization

Aqueous thermal polymerization of acrylonitrile (AN) initiated by peroxomonosulphate (HSO5-, PMS)-thiolactic acid (TLA) and PMS-thiomalic acid (TMA) redox systems has been carried out in the temperature range 30-50 °C. The effect of concentration of monomer, initiator, reducing agent, H+, and ionic strength on rate of polymerization, Rp, has been investigated under deaerated conditions. The Rp has been found to depend on, Rp ~ [AN]01.5 [PMS]0.5 [TLA]0.5 in PMS-TLA system and, Rp ~ [AN]02.0 [PMS]1.0 [TMA]0 in PMS-TMA system. The degree of polymerization (Xn) values and thermodynamic parameters have been evaluated. Suitable reaction scheme has been proposed and expressions for Rp and Xn have been obtained.

Effects of Doping on the Electrochemical and Electrical Properties of Poly(2,5-di(2-thienyl)pyrrole)

1999 ◽  
Vol 64 (8) ◽  
pp. 1357-1368 ◽  
Author(s):  
Enric Brillas ◽  
José Carrasco ◽  
Ramon Oliver ◽  
Francesc Estrany ◽  
Víctor Ruiz
Keyword(s):  
Mass Spectrometry ◽  
Fast Atom Bombardment ◽  
Oxidation Potential ◽  
Ethanolic Solution ◽  
Pt Electrode ◽  
Reversible Process ◽  
Oxidation Potentials ◽  
Lower Productivity ◽  
Polymeric Chains ◽  
Linear Molecules

The electropolymerization of 2,5-di(2-(thienyl)pyrrole) (SNS) on a Pt electrode from ethanolic solution with LiClO4 or LiCl as electrolyte has been studied by cyclic voltammetry (CV) and chronoamperometry (CA). In both media, a quasi-reversible process has been indicated by CV, reversing the scan at low oxidation potentials. Under these conditions, reducible positive charges formed in both oxidized polymers are compensated by the entrance of anions from solution. Elemental analysis reveals that polymers generated at a low oxidation potential by CA contain a 21.03% (w/w) of ClO4- or a 9.56% (w/w) of Cl-. The poly(SNS) doped with Cl- presents higher proportion of reducible positive charges, higher polymerization charge and lower productivity. A much higher electrical conductivity, however, has been found for the poly(SNS) doped with ClO4-. Both polymers are soluble in DMSO, acetone and methanol. The dimer, trimer, tetramer and pentamer have been detected as soluble and neutral linear oligomers by mass spectrometry-fast atom bombardment. The analysis of polymers by infrared spectroscopy confirms the predominant formation of linear molecules with α-α linkages between monomeric units. A condensation mechanism involving one-electron oxidation of all electrogenerated linear and neutral polymeric chains is proposed to explain the SNS electropolymerization.

Redox Potential - (Electronic) Structure Relationships in 18- and 17-Electron Mononitrile (or Monocarbonyl) Diphosphine Complexes of Re and Fe

2001 ◽  
Vol 66 (1) ◽  
pp. 139-154 ◽  
Author(s):  
M. Fátima C. Guedes Da Silva ◽  
Luísa M. D. R. S. Martins ◽  
João J. R. Fraústo Da Silva ◽  
Armando J. L. Pombeiro
Keyword(s):  
Cyclic Voltammetry ◽  
Electronic Structure ◽  
Binding Sites ◽  
Closed Shell ◽  
Carbonyl Complexes ◽  
Metal Centre ◽  
Pt Electrode ◽  
Metal Site ◽  
Oxidation Potentials ◽  
First Time

The organonitrile or carbonyl complexes cis-[ReCl(RCN)(dppe)2] (1) (R = 4-Et2NC6H4 (1a), 4-MeOC6H4 (1b), 4-MeC6H4 (1c), C6H5 (1d), 4-FC6H4 (1e), 4-ClC6H4 (1f), 4-O2NC6H4 (1g), 4-ClC6H4CH2 (1h), t-Bu (1i); dppe = Ph2PCH2CH2PPh2), or cis-[ReCl(CO)(dppe)2] (2), as well as trans-[FeBr(RCN)(depe)2]BF4 (3) (R = 4-MeOC6H4 (3a), 4-MeC6H4 (3b), C6H5 (3c), 4-FC6H4 (3d), 4-O2NC6H4 (3e), Me (3f), Et (3g), 4-MeOC6H4CH2 (3h); depe = Et2PCH2CH2PEt2), novel trans-[FeBr(CO)(depe)2]BF4 (4) and trans-[FeBr2(depe)2] (5) undergo, as revealed by cyclic voltammetry at a Pt-electrode and in aprotic non-aqueous medium, two consecutive reversible or partly reversible one-electron oxidations assigned as ReI → ReII → ReIII or FeII → FeIII → FeIV. The corresponding values of the oxidation potentials IE1/2ox and IIE1/2ox (waves I and II, respectively) correlate with the Pickett's and Lever's electrochemical ligand and metal site parameters. This allows to estimate these parameters for the various nitrile ligands, depe and binding sites (for the first time for a FeIII/IV couple). The electrochemical ligand parameter show dependence on the "electron-richness" of the metal centre. The values of IE1/2ox for the ReI complexes provide some supporting for a curved overall relationship with the sum of Lever's electrochemical ligand parameter. The Pickett parametrization for closed-shell complexes is extended now also to 17-electron complexes, i.e. with the 15-electron ReII and FeIII centres in cis-{[ReCl(dppe)2]}+ and trans-{FeBr(depe)2}2+, respectively.

scholarly journals Mitochondrial redox systems as central hubs in plant metabolism and signalling

2021 ◽  
Author(s):  
Olivier Van Aken
Keyword(s):  
Stress Responses ◽  
Plant Mitochondria ◽  
Nuclear Gene ◽  
Tca Cycle ◽  
Cellular Damage ◽  
Future Research ◽  
Antioxidant Systems ◽  
Plant Metabolism ◽  
Redox Systems ◽  
Glutathione Cycle

Abstract Plant mitochondria are indispensable for plant metabolism and are tightly integrated into cellular homeostasis. This review provides an update on the latest research concerning the organisation and operation of plant mitochondrial redox systems, and how they affect cellular metabolism and signalling, plant development and stress responses. New insights into the organisation and operation of mitochondrial energy systems such as the tricarboxylic acid (TCA) cycle and mitochondrial electron chain (mtETC) are discussed. The mtETC produces reactive oxygen and nitrogen species, which can act as signals or lead to cellular damage, and are thus efficiently removed by mitochondrial antioxidant systems, including Mn-superoxide dismutase, ascorbate-glutathione cycle and thioredoxin-dependent peroxidases. Plant mitochondria are tightly connected with photosynthesis, photorespiration and cytosolic metabolism, thereby providing redox-balancing. Mitochondrial proteins are targets of extensive post-translational modifications, but their functional significance and how they are added or removed remains unclear. To operate in sync with the whole cell, mitochondria can communicate their functional status via mitochondrial retrograde signalling to change nuclear gene expression, and several recent breakthroughs here are discussed. At a whole organism level, plant mitochondria thus play crucial roles from the first minutes after seed imbibition, supporting meristem activity, growth and fertility, until senescence of darkened and aged tissue. Finally, plant mitochondria are tightly integrated with cellular and organismal responses to environmental challenges such as drought, salinity, heat and submergence, but also threats posed by pathogens. Both the major recent advances and outstanding questions are reviewed, which may help future research efforts on plant mitochondria.

Assembly of thin mesoporous titania films and their effects on the voltammetry of weakly adsorbing redox systems

2005 ◽  
Vol 579 (2) ◽  
pp. 267-275 ◽  
Author(s):  
Katy J. McKenzie ◽  
Pauline M. King ◽  
Frank Marken ◽  
Catherine E. Gardner ◽  
Julie V. Macpherson
Keyword(s):  
Mesoporous Titania ◽  
Redox Systems ◽  
Titania Films
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