Zum Einfluß der intermolekularen Wechselwirkung auf den Depolarisationsgrad von Ramanlinien

A perturbation calculation is used to determine the effect of intermolecular interactions on the depolarization ratio of Raman lines. For highly polarized Raman lines an approximate formula is given, which enables the evaluation of the relative change of the anisotropy scattering using the change in the degree of depolarization.     

The source of excess linewidth in EPR of triplet excitons in molecular crystals

It is shown that the EPR linewidth spectrum of triplet excitons in molecular crystals can be severely distorted by weak orientational disorder. The demonstration employs a one-parameter correction procedure based on the assumption that the angular dependence of excess width is directly proportional to the angular gradient of the resonant field. Application to the discrepant data of Haarer and Wolf brings them into agreement with theory and with more recent experiments. A phenomenological model of the disorder is used to interpret the distortion parameter. These results suggest the potential value of exciton EPR as a probe of structural imperfections in molecular crystals.     

Thermal and electronic transport properties and two-phase mixtures in La(5/8-x)Pr(x)Ca(3/8)MnO3

We measured thermal conductivity kappa, thermoelectric power S, and electric conductivity sigma of La(5/8-x)Pr(x)Ca(3/8)MnO3, showing an intricate interplay between metallic ferromagnetism (FM) and charge ordering (CO) instability. The change of kappa, S, and sigma with temperature (T) and x agrees well with the effective medium theories for binary metal-insulator mixtures. This agreement clearly demonstrates that with the variation of T as well as x, the relative volumes of FM and CO phases drastically change and percolative metal-insulator transition occurs in the mixture of FM and CO domains.     

Rheological evidence for a dynamical crossover in polymer melts via nonequilibrium molecular dynamics

A certain "critical" molecular weight controls rheological properties of the multibead finitely extensible nonlinear elastic (FENE) chain model polymer melt. The rheological crossover manifests itself in a change of power law behavior for the viscous properties at a critical number of beads per chain N(c) = 100+/-10. This finding confirms a newly proposed relationship between dimensionless critical weight, characteristic length, and flexibility which we obtain as a side result. Results further suggest that the entanglement molecular weight N(e) for the flexible FENE chain model could be comparable in size or even larger than its critical molecular weight N(c).     

On the Pettis Integral of Closed Valued Multifunctions

In this work, the study of Pettis integrability for multifunctions (alias set-valued maps), whose values are allowed to be unbounded, is initiated. For this purpose, two notions of Pettis integrability, and of Pettis integral, are considered and compared. The first notion is similar to that of the weak integral, already known for vector-valued functions, and is defined via support functions. The second notion resembles the classical Aumann definition using integrable selections, but it involves the Pettis integrable selections rather than the Bochner integrable ones. The above two integrals are shown to coincide in a quite general setting. Several criteria for a multifunction to be Pettis integrable (in one sense or the other) are proved. On the other hand, due to the possibility of infinite values for the support functions, we are led to introduce a more general notion of scalar integrability involving the negative part of these functions. We compare the scalar integrability of a multifunction with that of its measurable selections. We also provide some new results concerning multifunctions with bounded values and/or new proofs of already existing ones. Examples are included to illustrate the results and to introduce open problems.     

An efficient inversion algorithm for atmospheric remote sensing with application to UV limb observations

In this paper we present a retrieval algorithm for atmospheric remote sensing. The algorithm combines Tikhonov regularization and the iteratively regularized Gauss-Newton method and is devoted to the solution of multi-parameter inverse problems with simple bounds on the variables. The basic features of the algorithm: the solution of the bound-constrained minimization problem, the selection of the optimal regularization parameter, the derivation of the global regularization matrix and the characterization of the solution (error analysis) are discussed in detailed. The inversion algorithm is applied to ozone retrieval from SCIAMACHY limb scatter measurements in the ultraviolet spectral range.