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'Belousov Zhabotinsky Reaction' in keywords Facet section ZfN Section A [X]

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1	Author	H. D. Försterling, H. Schreiber	Requires cookie*
	Title
	Abstract	The reaction HBr02 + Br " + H + -»2 HOBr, which is the most important control reaction in the Belousov-Zhabotinsky (BZ) system, is investigated in competition to the AgBr precipitation reaction Ag+ + Br" — ► AgBr. It turns out that the bromite-bromide reaction starts even in the presence of Ag^ in high concentration; the rate of consumption of bromite by bromide, however, is slowed down significantly if silver ions are present in the system. The experiments reveal that the AgBr precipita tion reaction proceeds in a series of several steps, starting with a fast equilibrium. This way different experimental results on the influence of silver ions on the kinetics of the BZ reaction may now be better understood.
	Reference	Z. Naturforsch. 43a, 956—960 (1988); received August 8 1988
	Published	1988
	Keywords	Belousov-Zhabotinsky Reaction, Bromous Acid, Bromide, Silver Bromide
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	TEI-XML for	default:Reihe_A/43/ZNA-1988-43a-0956.pdf
	Identifier	ZNA-1988-43a-0956
	Volume	43

2	Author	Szilvia Murányi, Horst-Dieter Försterling	Requires cookie*
	Title	Chloride Induced Oscillations in the Classical Belousov-Zhabotinsky Reaction Explained by the "Radicalator"-Model
	Abstract	We detected non-bromide controlled oscillations, which appear in a classical Belousov-Zhabotin-sky (BZ) system at a high malonic acid/bromate ratio in the presence of added chloride. The oscillations start immediately after the addition of the catalyst. To explain the oscillations we assume control by a synergetic process involving both chloride ions and malonyl radicals. The experiments are well in accordance with calculations based on the "Radicalator" model. This model is also capable of explaining the rate of formation of C0 2 in the BZ system.
	Reference	Z. Naturforsch. 45a, 135—144 (1990); received October 24 1989
	Published	1990
	Keywords	Belousov-Zhabotinsky reaction, Bromous acid, Chloride, Autocatalysis
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	TEI-XML for	default:Reihe_A/45/ZNA-1990-45a-0135.pdf
	Identifier	ZNA-1990-45a-0135
	Volume	45

3	Author	H. D. Försterling, R. Pachl, H. Schreiber	Requires cookie*
	Title	Oxidation of Malonic Acid by Ceric Ions Subset of the Belousov-Zhabotinsky Reaction
	Abstract	The kinetics o f the Ce4+ -decay and the formation o f C 0 2 are measured in sulfuric acid solutions o f m alonic acid. The reaction rate is slowed down by Ce3+ -ions due to a reaction o f Ce3+ with m alonic acid radicals. The primary source o f C 0 2 is the decarboxylation o f m alonic acid radicals. Implications on the mechanism o f the BZ reaction are discussed.
	Reference	Z. Naturforsch. 42a, 963—9 (1987); received July 10 1987
	Published	1987
	Keywords	Belousov-Zhabotinsky Reaction, M alonic Acid, M alonic Acid Radical, C 0 2, Ce4+
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0963.pdf
	Identifier	ZNA-1987-42a-0963
	Volume	42

4	Author	Horst-Dieter Försterling, Szilvia Murányi, Helmut Schreiber	Requires cookie*
	Title
	Abstract	In the Belousov-Zhabotinsky system bromine species of oxidation states — 1 to 5 are important for the start and for the inhibition of the autocatalytic reaction steps. Especially, the reaction of Br~ with HBr02 competes with the oxidation of Ce3+ by BrOz formed from HBrO, and HBr03. In our investigation the reaction of Br with HBr02 (solvent 1 M sulfuric acid) is followed spectroscopi-cally in a mixture of bromine and hypobromous acid, which system works as a buffer for bromide. Including experiments on the hydrolysis of Br2 and on the solubility product of AgBr in 1 M sulfuric acid solution direct information about the rate constant kl of the Br~/HBrO, reaction is obtained (fc, = 2.5 x 106 M"2 s"1 at 20 C and 4x 106 M"2 s"1 at 25°C, which values are valid in the range of 0.01 to 1 M sulfuric acid). R a te o f th e B ro m o u s A c i d -B r o m i d e R e a c tio n
	Reference	Z. Naturforsch. 44a, 555 (1989); received March 15 1989
	Published	1989
	Keywords	Belousov-Zhabotinsky reaction, Bromous acid Bromide, Bromine hydrolysis, Bromate, Dual wavelength spectroscopy
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0555.pdf
	Identifier	ZNA-1989-44a-0555
	Volume	44

5	Author	Horst-Dieter Försterling, Szilvia Murányi	Requires cookie*
	Title	Contribution of Malonyl Radical Control in the Classical Belousov-Zhabotinsky Reaction
	Abstract	In the original theory of the Belousov-Zhabotinsky reaction it is assumed that the oscillations are exclusively controlled by bromide ions. From uv/vls and ESR experiments on BZ systems started with Ce 4+ we conclude that malonyl radicals play an important role as additional intermediates. The experiments are in agreement with calculations based on the Radicalator model.
	Reference	Z. Naturforsch. 45a, 1259—1266 (1990); received July 15 1990
	Published	1990
	Keywords	Belousov-Zhabotinsky reaction, Cerium, Malonic acid, Bromate, Bromide, Feedback, Malonyl radicals
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	TEI-XML for	default:Reihe_A/45/ZNA-1990-45a-1259.pdf
	Identifier	ZNA-1990-45a-1259
	Volume	45