Search Results - (Author, Cooperation:R. Knochenmuss)
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1Latest Papers from Table of Contents or Articles in PressS. Hannedouche ; J. Zhang ; T. Yi ; W. Shen ; D. Nguyen ; J. P. Pereira ; D. Guerini ; B. U. Baumgarten ; S. Roggo ; B. Wen ; R. Knochenmuss ; S. Noel ; F. Gessier ; L. M. Kelly ; M. Vanek ; S. Laurent ; I. Preuss ; C. Miault ; I. Christen ; R. Karuna ; W. Li ; D. I. Koo ; T. Suply ; C. Schmedt ; E. C. Peters ; R. Falchetto ; A. Katopodis ; C. Spanka ; M. O. Roy ; M. Detheux ; Y. A. Chen ; P. G. Schultz ; C. Y. Cho ; K. Seuwen ; J. G. Cyster ; A. W. Sailer
Nature Publishing Group (NPG)
Published 2011Staff ViewPublication Date: 2011-07-29Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Animals ; Antibody Formation/immunology ; B-Lymphocytes ; Cell Line ; Cell Movement/drug effects ; Gene Expression Profiling ; Gene Expression Regulation/drug effects/immunology ; Humans ; Hydroxycholesterols/chemistry/*pharmacology ; Liver/chemistry ; Mice ; Mice, Knockout ; Receptors, Cell Surface/*immunology ; Receptors, G-Protein-Coupled ; Sheep ; T-Lymphocytes/immunologyPublished by: -
2Articles: DFG German National LicensesKnochenmuss, R. ; Leutwyler, S.
College Park, Md. : American Institute of Physics (AIP)
Published 1992Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: Fully optimized structures were calculated for (H2O)n, n=5 and 8, at the SCF (self-consistent field) level using the 4–31G and, for n=5, also 6–31G* basis sets. The n=5 cluster was found to have a cyclic structure with five H bonded and five free hydrogens. The n=8 minimum energy structure has almost D2d symmetry, with an approximately cubical oxygen framework and four tetrahedrally arranged free hydrogens; four of the water molecules are single- and four are double-hydrogen donors. Harmonic vibrational frequencies, IR and Raman intensities were calculated for n=5 and 8, as well as for the previously optimized n=2–4 clusters. The band positions and intensities in the 3000–3800 cm−1 region correlate well with IR predissociation spectra of (H2O)n clusters. The O–H stretching frequencies of single- and double-hydrogen donor water molecules are relatively well separated from each other, and both from the frequency region of the free O–H stretches, suggesting a new interpretation for some of the data. The low-frequency translational/librational modes of both n=5 and 8 show strong mixing with intramolecular stretching and bending. The stretch–stretch coupling constants for OH oscillators on different molecules kij(OH,OH) show a strong increase, and those for intramolecular coupling kii(OH,OH) a rapid decrease with increasing cluster size. For n≥5, kij(OH,OH)(very-much-greater-than)kii(OH,OH), implying that the cluster can be viewed as a supermolecule of strongly coupled O–H oscillators. The n=8 spectra show significant similarity to those of ice.Type of Medium: Electronic ResourceURL: -
3Articles: DFG German National LicensesKnochenmuss, R. ; Leutwyler, S.
College Park, Md. : American Institute of Physics (AIP)
Published 1990Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: Two size-selective spectroscopic techniques were used to experimentally differentiate between nearly rigid (solid-like) and highly fluxional (liquid-like) carbazole⋅Arn (n=4–6) clusters produced and cooled in supersonic molecular beams: (1) ionization potential selective resonant two-photon ionization (IP selective R2PI) spectroscopy; and (2) spectral hole-burning with R2PI detection. For each cluster size, separate and qualitatively very different electronic spectra were obtained by IP selective R2PI, depending on total ionization energy. At low ionization energies, broad bands of halfwidth ≈50 cm−1 (FWHM) were obtained, which are interpreted as due to fluxional clusters of high internal energy. When ionizing slightly above an abrupt step in the ionization efficiency curve, additional narrow (Δν≈5 cm−1) features appear superimposed on the semicontinuous spectra; these are interpreted as due to (near) rigid clusters with low internal energy. The spectral hole-burning experiments support this interpretation in that deep holes of ≈5 cm−1 width could be burned in the rigid cluster spectra, but no spectral holes could be observed in the broad bands. The latter fact is interpreted as due to spectral diffusion of the fluxional subpopulation on a 10−8 s or faster time scale. These results are in good agreement with conclusions drawn from recent numerical simulations.Type of Medium: Electronic ResourceURL: -
4Articles: DFG German National LicensesKnochenmuss, R. ; Güdel, H. U.
College Park, Md. : American Institute of Physics (AIP)
Published 1987Staff ViewISSN: 1089-7690Source: AIP Digital ArchiveTopics: PhysicsChemistry and PharmacologyNotes: The dynamics of exciton motion in tetramethylammonium manganese (II) trichloride (TMMC) are investigated in the presence of copper (II) and cobalt (II) traps. Manganese luminescence decay curves are analyzed using several models and at various trap concentrations and temperatures, with the conclusion that trapping does not occur on every encounter. Trapping efficiencies are about 10−4. On-chain transport is found to be incoherent, with hop rates of approximately 1012 s−1 at 273 K and 1011 s−1 at 160 K. The Mn to trap rates and the rate of hopping between trap-limited chain segments are also estimated.Type of Medium: Electronic ResourceURL: -
5Articles: DFG German National LicensesStaff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
6Articles: DFG German National LicensesStaff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesStaff View
ISSN: 0009-2614Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002Topics: Chemistry and PharmacologyPhysicsType of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesLeutwyler, S. ; Furlan, A. ; Knochenmuss, R. ; Schütz, M. ; Troxler, T. ; Wülfert, S.
Springer
Published 1991Staff ViewISSN: 1434-6079Keywords: 68.45 Gd ; 33.10.Gx ; 33.80. − b ; 36.40. + dSource: Springer Online Journal Archives 1860-2000Topics: PhysicsNotes: Abstract At the atomic size level, descriptions of rearrangement of structures and shapes of molecules are couched in chemical terminology (isomerization, racemization, rearrangement, etc.). In bulk solids, structural changes are described on a collective scale as order-disorder transformations and phase transitions (melting). To describe structural changes in atomic and molecular clusters we employ elements of both pictures:(a) local bonding rearrangements in molecules, and(b) collective permutational and/or translational rearrangements in the bulk. Various examples are given of isomerism and collective structural transformations in clusters.Type of Medium: Electronic ResourceURL: