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Aufsatz
Lexikalische Ellipsen. Fragen und Vorschläge
(1991)
Sieht man die einschlägige Fachliteratur auf Belege durch, fühlt man sich von der unerwarteten Fülle der als (relativ) kontextunabhängig charakterisierten Ellipsen geradezu erschlagen. Vor einer Untersuchung ist man demnach vor folgende Alternative gestellt: Entweder man folgt der bisherigen Praxis und analysiert einige (wie auch immer ausgewählte) Beispiele oder man versucht, ausgehend von einem größeren Material, zumindest manche der Probleme, die einer Lösung harren oder die in exemplarischen Analysen erst gar ...
Aufsatz
Grammatische Korrektheit als typologisches Problem
(1991)
Dem Begriff der grammatischen Korrektheit (Grammatikalität) kommt sowohl im Muttersprach- wie auch im Fremdsprachenunterricht nach wie vor zentrale Bedeutung zu. Da jeder Sprachunterricht Unterricht einer bestimmten Sprache ist, wächst dieser Begriff wie natürlich mit dem der Einzelsprache zusammen: Korrekt/grammatikalisch ist der Satz oder das Syntagma (evtl. der Text) X der Sprache L.
Aufsatz
Prediction of some thermodynamic properties of selected compounds of element 104
(1991)
A set of parametrized equations has been published by Bratsch and Lagowski for calculating thermodynamic properties of the lanthanides, actinides, element 104, and certainrelated elements. Since these equations were applied to element 104, new values for the first four ionization energies and radii of the ions of charge +1, +2, +3, and +4 have been calculated for this element. The parametrized equations are used here with these new values to calculate some thermodynamic properties of element 104.
Aufsatz
Two-photon decay of the 1s2s ^1S_0 state in _36Kr^34+ produced by resonant transfer and excitation
(1991)
The doubly excited 2s2p ^1P_1 level of Kr^{34+} populated via resonant transfer and excitation (RTE) feeds selectively the metastable ls2s ^1 S_0 state which can only decay via simultaneous emission of two photons to the ground state 1s^2 ^1 S_0. X-ray/X-ray coincidence measurements in heavy ionatom collisions enable the direct measurement of the spectral distribution of the two-photon decay in He-like ions. In addition, we observe strong photon cascades indueed by radiative electron capture.
Aufsatz
Further investigations on doubly excited four-electron ions: beam-foil experiment and MCDF theory
(1991)
In continuation of our previous work on the quintet transitions 1s2s2p^2 ^5 P-1s2s2p3d ^5 P^0, ^5 D^0, results on other n = 2 - n' = 3 quintet transitions for elements N, 0 and F are presented. Assignments have been established by comparison with Multi-Configuration Dirac-Fock calculations. High spectral resolution on beam-foil spectroscopy was essential for the identification of most of the lines. For some of the quintet lines decay curves were measured, and the lifetimes extracted were found to be in reasonable ...
Aufsatz
Femtosecond time-resolved wave packet motion in molecular multiphoton ionization and fragmentation
(1991)
The dynamics of molecular multiphoton ionization and fragmentation of a diatomic molecule (Na_2) have been studied in molecular beam experiments. Femtosecond laser pulses from an amplified colliding-pulse mode-locked (CPM) ring dye laser are employed to induce and probe the molecular transitions. The final continuum states are analyzed by photoelectron spectroscopy, by ion mass spectrometry and by measuring the kinetic energy of the formed ionic fragments. Pump-probe spectra employing 70-fs laser pulses have been ...
Aufsatz
Femtosecond time-resolved molecular multiphoton ionization: the Na_2 system
(1991)
We report here the first experimental study of femtosecond time-resolved molecular multiphoton ionization.
Femtosecond pump-probe techniques are combined with time-of-flight spectroscopy to measure
transient ionization spectra of Na_2 in a molecular-beam experiment. The wave-packet motions in
different molecular potentials show that incoherent contributions from direct photoionization of a singly
excited state and from excitation and autoionization of a bound doubly excited molecular state determine
the observed ...