Die Bestimmung des Morphin-Gehaltes im Opium

Ohne Zusammenfassung     

An analytic formula for Macdonald polynomials

We give the explicit analytic development of any Jack or Macdonald polynomial in terms of elementary (resp. modified complete) symmetric functions. These two developments are obtained by inverting the Pieri formula. To cite this article: M. Lassalle, M. Schlosser, C. R. Acad. Sci. Paris, Ser. I 337 (2003).     

Ambiguity functions, Wigner distributions and Cohen's class for LCA groups

In this paper we construct a general class of time-frequency representations for LCA groups which parallel Cohen's class for the real line. For this, we generalize the notion of ambiguity function and Wigner distribution to the setting of general LCA groups in such a way that the Plancherel transform of the ambiguity function coincides with the Wigner distribution. Furthermore, properties of the general ambiguity function and Wigner distribution are studied. In detail we characterize those groups whose ambiguity functions and Wigner distributions vanish at infinity or are square-integrable. Finally, we explicitly construct Cohen's class for the group of p-adic numbers, p prime.     

Konfiguration und konformation von methyl- und aminylradikalen mit CF3S-substituenten

From the hyperfine ESR-splitting patterns of, $\text{a(}{}^{13}\text{C}{}_{\mathrm{\gamma }}\text{), a(}{}^{14}\text{N}\text{)}\text{and}\text{a(}{}^{19}\text{F}\text{)}$ it is concluded that the radicals (CF₃S)₃C·, (CF₃S)₂HC·, (CF₃S)H₂C·, (CF₃S)₂N· and (CF₃S)₃Si· are planar π-radicals existing in a nearly fully staggered conformation. The force which promotes the staggered conformation arises from conjugative delocalization between the 2 p_z-unpaired electron and the p-type lone pair on the sulfur atoms of the CF₃S-groups, causing a stabilization of the radicals. The electronegative CF₃-group decreases the extent of conjugative electron delocalization.Whereas fluorine atoms adopt equivalent positions in the radicals the staggered conformation implies inequivalence of the protons in CF₃SCH₂.     

Bridging the final gap in stereocontrolled wittig reactions: methoxymethoxy-armed allylic phosphorus ylides affording conjugated dienes with high cis selectivity

After treatment with an appropriate base (butyllithium or sodium amide), 2-alkenyltris(2-methoxymethoxyphenyl)phosphonium salts carrying an allyl, crotyl, or prenyl (3-methyl-2-butenyl) side chain condense with saturated or unsaturated aldehydes to give conjugated dienes with Z/E ratios ranging from 90:10 to > 99:1 and averaging 96:4. Owing to steric congestion, yields are only moderate (on average 41%; extremes 10-79%). The nonvolatile tris(2-methoxymethoxyphenyl)phosphine oxide by-product can be readily isolated and reduced to recover the phosphane starting material, or it may be hydrolyzed to the water-soluble tris(2-hydroxyphenyl)phosphine oxide.     

Recent development in dielectric relaxation spectroscopy of polymers

An evaluation strategy for dielectric measurements in the frequency and/or time domain is presented which provides complete information about a relaxation mechanism (intensity, position, and shape of the relaxation function) independent of overlapping with neighboring mechanisms. As an example results on poly-(ethyleneterephthalate) are given.     

Multiconfiguration self-consistent field theory of localized orbitals: The secular problem

In MC SCF theory both the orbitals and the wavefunction expansion coefficients are optimized by minimizing the energy of the system with respect to arbitrary variations of the orbitals and the wavefunction expansion coefficients. This procedure leads to separate equations for the optimal orbitals and to the secular equation for the expansion coefficients which must be solved self-consistently. In a previous paper we discussed the properties of several different choices of localization potential which may be used in the orbital equation. In this paper we derive an alternative native secular equation by making use of the transformation properties of the localized orbitals. This secular equation is considerably simpler than the conventional secular equation and leads to a simplified scheme for the self-consistent solution of the orbital and secular equations.     

Dielectric relaxation in polymeric solids Part 1. A new model for the interpretation of the shape of the dielectric relaxation function

A model is proposed which explains the shape of the dielectric relaxation function at the glass transition of polymers. The model is based on the idea that the molecular mobility at the glass transition is controlled by intra- and intermolecular interaction. In addition, a specific model for the local chain dynamics in amorphous polymer systems is used. According to the scaling hypothesis of molecular dynamics the model relates the high frequency dependence of the dielectric loss curve to the local chain dynamics and the low frequency dependence to the intermolecular correlation.