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'Redox Potentials' in keywords

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1	Author	G. Abou-Elenien+, J. Rieser++, N. Ismail+++, K. Wallenfels	Requires cookie*
	Title	Elektrochemische Eigenschaften von Dihydropyridin-und Pyridinderivaten Electrochemical Properties of Pyridine and Dihydropyridine Derivatives
	Abstract	The electrochemical oxidation and reduction properties of different dihydropyridines and pyridines have been investigated in non aqueous solvent as benzonitrile and aceto-nitrile with tetra-n-butylammonium perchlorate as supporting electrolyte at platinium electrodes using DC-voltametry, cycl. voltametry and coulometry. Possible redox-mechanisms are discussed.
	Reference	Z. Naturforsch. 36b, 386—390 (1981); eingegangen am 26. November 1980
	Published	1981
	Keywords	Pyridines, Dihydropyridines, Electrochemical Behavior, Redox-Potentials
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	TEI-XML for	default:Reihe_B/36/ZNB-1981-36b-0386.pdf
	Identifier	ZNB-1981-36b-0386
	Volume	36

2	Author	Michael Neumann-Spallart, K. Kalyanasundaram	Requires cookie*
	Title	On the One and Two-Electron Oxidations of Water-Soluble Zinc Porphyrins in Aqueous Media
	Abstract	The one and two-electron oxidations of water soluble ionic zinc porphyrins (Zinctetra-methylpyridylporphyrin, ZnTMPyP, Zinc-tetra-p-sulfonato-phenyl-porphyrin, ZnTPPS, and Zinc-tetra-p-carboxy-phenylporphyrin, ZnTPPC) leading to the porphyrin /7-cations and /7-dications have been investigated in water by electrochemical (cyclic voltammetry and controlled potential electrolysis) and chemical methods. The half-wave potentials for the oxidation are shown to be markedly dependent on the charge on the /?-substituents. While the one-electron oxidations for all these porphyrins are reversible, the dication formation leads to labile isoporphyrins as intermediates.
	Reference	Z. Naturforsch. 36b, 596—600 (1981); received December 1 1980/February 19 1981
	Published	1981
	Keywords	Redox Potentials, yr-Cation Radicals, Electrochemistry
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	TEI-XML for	default:Reihe_B/36/ZNB-1981-36b-0596.pdf
	Identifier	ZNB-1981-36b-0596
	Volume	36

3	Author	Berthold Kiefer, Helmut Sapper, WolfgangL. Ohm Ann	Requires cookie*
	Title	The Influence of Amino Acid Ligands and Vitamin C on the Reduction Potential of Fe(III): Polarographie and Electron Spin Resonance Investigations
	Abstract	The pH dependence o f Fe(III)-am ino acid com plexes has been studied polarographically and by means o f ESR spectroscopy. It could be shown that, at least, two com plexes exist: one with a low m olecular weight, ESR detectable at acid pH. and one with a high molecular w eight at alkaline pH, ESR non detectable. The half wave potential o f Fe (III) is lowered by am ino acid ligands. The redox interaction o f the Fe(III)-amino acid com plexes with vitam in C results in a decrease o f the ascorbyl radical concentration. Ascorbic acid also forms a com plex with Fe(III) as in dicated by a polarographic half wave potential near -0.55 V vs. S.C.E. at pH 7.
	Reference	Z. Naturforsch. 39c, 102—106 (1984); received September 22 1983
	Published	1984
	Keywords	Ferrous Ions Ascorbic Acid, Redox-Potential, Polarography, ESR -Spectroscopy
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	TEI-XML for	default:Reihe_C/39/ZNC-1984-39c-0102.pdf
	Identifier	ZNC-1984-39c-0102
	Volume	39

4	Author	Alena Novoselova, Vladimir Shishkin, Vladimir Khokhlov	Requires cookie*
	Title	Redox Potentials of Samarium and Europium in Molten Lithium Chloride
	Abstract	The samarium (III)/(II) and europium (III)/(II) redox potentials in molten lithium chloride were measured using the direct potentiometric method in the temperature range from 923 to 1094 K. Glassy carbon was used as the indifferent working electrode, and the standard chlorine electrode as a reference. The total concentration of rare-earth chlorides dissolved in molten lithium chloride did not exceed 4.5 mol%.
	Reference	Z. Naturforsch. 56a, 754—756 (2001); received August 20 2001
	Published	2001
	Keywords	Molten Salts, Redox Potentials, Samarium Chlorides, Europium Chlorides, Lithium Chloride
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	TEI-XML for	default:Reihe_A/56/ZNA-2001-56a-0754.pdf
	Identifier	ZNA-2001-56a-0754
	Volume	56

5	Author	WernerH. Kalus, WilliamG. Filby	Requires cookie*
	Title	Is there an Equilibrium between A scorbic and Dehydroascorbic Acids?
	Abstract	The previously reported interaction between ascorbate monoanion and dehydroascorbic acid yielding semidehy-droascorbic acid has been shown to be therm odynam ically unfeasible and non-existent. N o evidence for radical for mation in the reinvestigation o f the reaction using ESR spectroscopy under careful exclusion o f air could be found. Our results show that the detection o f the free radical in earlier studies resulted from the reaction of ascorbate with traces of oxygen and/o r metals.
	Reference	Z. Naturforsch. 36c, 1088—1090 (1981); received May 19 1981
	Published	1981
	Keywords	Ascorbic Acid, Dehydroascorbic Acid, Redox Potential, Free Radical, ESR
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	TEI-XML for	default:Reihe_C/36/ZNC-1981-36c-1088_n.pdf
	Identifier	ZNC-1981-36c-1088_n
	Volume	36

6	Author	Alena Novoselova, Vladimir Khokhlov, Vladimir Shishkin	Requires cookie*
	Title	Thermodynamic Characteristics of Samarium and Europium Chlorides in Molten Alkali Metal Chlorides
	Abstract	The formal standard redox potentials of samarium (III)/(II) (EZmi+/ Smi+) and europium (III)/(II) (• £, £u3+/eu2+) *n molten alkali metal chlorides were measured potentiometrically against a reference chlorine electrode. The Gibbs energy changes and equilibrium constants for the reaction LnCl2(D + V2 Cl2(g) LnCl3(I) were calculated for the salt systems studied. The effect o f the cationic composition of the melt-solvent on the above thermodynamic characteristics is also reported.
	Reference	Z. Naturforsch. 56a, 837—840 (2001); received August 20 2001
	Published	2001
	Keywords	Thermodynamic Stability, Rare Earth Chlorides, Molten Alkali Metal Chlorides, Redox Potentials, Gibbs Energy Changes
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	TEI-XML for	default:Reihe_A/56/ZNA-2001-56a-0837.pdf
	Identifier	ZNA-2001-56a-0837
	Volume	56