Key to xenobiotic carotenoids

A listing of carotenoids with heteroatoms (X = F, Cl, Br, I, Si, N, S, Se, Fe) directly attached to the carotenoid carbon skeleton has been compiled. The 178 listed carotenoids with C, H, X atoms demonstrate that the classical division of carotenoids into hydrocarbon carotenoids (C, H) and xanthophylls (C, H, O) has become obsolete.     

Quantitative Bestimmung von Mono- und Dienen in Kohlenwasserstoffgemischen

Zusammenfassung Konjugierte Diene und Monoene werden colorimetrisch in Kohlenwasserstoffgemischen durch Kupplung mit diazotiertem p-Phenylendiamin bestimmt. Die Methode ermöglicht auch die Bestimmung beider Kohlenwasserstoffgruppen nebeneinander.

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Summary Conjugated dienes and monoenes may be determined in mixtures of hydrocarbons by colorimetry of the dye obtained by coupling with diazotized p-phenylenediamine. Both groups of hydrocarbons can also be determined in presence of each other.

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Der ESSO-AG Hamburg danken wir für weitreichende Unterstützung der vorliegenden Arbeit und für die Erlaubnis, die gefundenen Resultate zu veröffentlichen.

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Herrn Prof. Dr. C. Mahr zum 65. Geburtstag gewidmet.

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Marxmeier, H.: Diplom-Arbeit, Marburg 1960.

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Wolf, W.: Staatsexamensarbeit, Marburg 1962.     

Reaktionen an komplexgebundenen liganden : XXXIII. Synthese,reaktivität und struktur von eisen-carbonyl-komplexen mit vierzähnigen thioäther-thiolato-liganden

The reaction of the anion [Fe(CO)₂(S₂C₆H₄)₂]^2? with 1,2-C₂H₄Br₂ yields [Fe(CO)₂(dttd)] containing the dianion of the new tetradentate thioether-thiol ligand 2,3,8,9-dibenzo-1,4,7,10-tetrathiadecan (dttd-H₂). Iron(II) salts coordinate CO under normal conditions also in the presence of alkyl mercaptides; the reaction of, e.g., Fe²⁺, 1,2-S₂C₂H₄^2? and CO yields [Fe(CO)₂(S₂C₂H₄)]^2? which reacts with 1,2-C₂H₄Br₂ analogously yielding [Fe(CO)₂(tdd)], (ttd = [1,4,7,10-tetrathiadecane]^2?). As shown by X-ray analysis the iron centre in [Fe(CO)₂(ttd)] is coordinated pseudo-octahedrally by four sulfur atoms and two cis-carbonyl groups. [Fe(CO)₂(dttd)] splits off one CO ligand upon heating in THF yielding [Fe(CO)(dttd)], which on reaction with PMe₃ yields [Fe(CO)(PMe₃)(dttd)]. The new complexes are characterized by elemental analyses as well as by IR, ¹H NMR and mass spectroscopy.     

Pattern formation in flowing electrorheological fluids

A two-fluid continuum model is developed to describe mass transport in electro- and magnetorheological suspensions. The particle flux is related to the field-induced stresses. Solutions of the resulting mass balance show column formation in the absence of flow, and stripe formation when a suspension is subjected simultaneously to an applied electric field and shear flow.     

Qualitative anorganische Analyse mittels Papierchromatographie, Trennungsgang der gebr?uchlichen Kationen

Ohne Zusammenfassung     

Trennung der Schwefelwasserstoffgruppe mit Hilfe der Papierchromatographie

Ohne Zusammenfassung     

A partial-wave analysis for proton compton scattering in the Δ(1232) energy region

Based on the nowadays available phenomenological multipoles for pion photoproduction, a systematic dispersion theoretic calculation of Compton partial amplitudes has been performed. By comparing with the new experimental data in the Δ(1232) region it is found that the hitherto existing discrepancies between the data and theory remain. Our results allow us to isolate the basis of this problem. It is due to the fact that the imaginary parts of the Compton amplitudes determined already by unitarity, give too large contributions to the cross section thus leaving no space for real parts required by the dispersion integrals.Therefore a simultaneous partial-wave analysis for Compton scattering and pion photoproduction was carried through employing only the unitarity connections between both. The resulting amplitudes give a good fit to the Compton cross section and all photoproduction data; moreover the photoproduction multipoles agree essentially with those of the previous analyses. On the other hand for Compton scattering, phenomenological amplitudes are obtained for the first time and a model independent test of dispersion theoretic amplitudes can be carried out. For the resonating f_MM¹⁺ amplitude which describes the M1 excitation and deexcitation to the Δ-isobar, large discrepancies have been found. Possible consequences especially for the forward scattering amplitude and the validity of the Kramers-Kronig relation are discussed.