Bartel, Hans

Not all encounters in the reaction of 02 with eaq" lead to 02 ", and the appropriate spin factor for this is 2/3 because of the large zero-field splitting of triplet 02 (Schmidt et al. 1995). Similarly, spin dephasing is observed for the reaction of H with 02 (Han and Bartels 1994), and this may apply also to other R plus 02 reactions. 

Han P, Bartels DM (1994) Encounters of H and D atoms with 02 in water relative diffusion and reaction rates. In Gauduel Y, Rossky P (eds) AIP conference proceedings 298. "Ultrafast reaction dynamics and solvent effects." AIP Press, New York, 72 pp Hasegawa K, Patterson LK (1978) Pulse radiolysis studies in model lipid systems formation and behavior of peroxy radicals in fatty acids. Photochem Photobiol 28 817-823 Herdener M, Heigold S, Saran M, Bauer G (2000) Target cell-derived superoxide anions cause efficiency and selectivity of intercellular induction of apoptosis. Free Rad Biol Med 29 1260-1271 Hildenbrand K, Schulte-Frohlinde D (1997) Time-resolved EPR studies on the reaction rates of peroxyl radicals of polyfacrylic acid) and of calf thymus DNA with glutathione. Re-examination of a rate constant for DNA. Int J Radiat Biol 71 377-385 Howard JA (1978) Self-reactions of alkylperoxy radicals in solution (1). In Pryor WA(ed) Organic free radicals. ACS Symp Ser 69 413-432... 

Diffusion coefficients were reported to be (7.0 1.5) x 10 m s for H in H2O and (5.0 1.0) x 10" m s for D in D2O [36]. After correction for the different viscosities of H2O and D2O one obtains Dy Do = 1.41 0.46, which is compatible with 7/2 but also with unity, and it matdies the presumably more accurate relative value of ca. 1.10 that was deduced by Han and Bartels fiom EPR dephasing rates in the reaction of the isotope with molecular oxygen [37], assuming that it is diffusion controlled. On the same basis, DmJDh was determined to be 2.0 0.2, indicating that Mu difiuses in water significantly ftister than H [3S]. 

Research by the chemist Ludwig Ziehl presents yet another example of war materials research at the Institute. While still an undergraduate in 1944-1945, Ziehl conducted experiments with a model, stainless-steel combustion chamber in the basement of the partly destroyed KWI for Chemistry. His secret apparatus consisted of a sealed reaction chamber with a window through which the combustion of the samples, probably fuels and fuel additives, could be directly observed. Like Werner Wittstadt and Hans Bartel, Ziehl was among the members of the Institute who would follow Thiessen to the USSR in the fall of 1945 and become involved with the Soviet atomic bomb program. As an expert physical chemist, Thiessen himself evaluated and tested some, often rather fanciful, ideas for Nazi wonder weapons which had been sent to the authorities. ... 

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