Die Elektrolytwirkung auf organische isokolloide Systeme

Ohne Zusammenfassung     

Synthese des 2, 3-Pyridinoacenaphtens

Ohne Zusammenfassung     

Über die Erden des Gadolinits von Ytterby

Ohne ZusammenfassungZum Schlusse sei mir noch gestattet, dem Herrn Prof. Dr. A. Lie ben und seinem Assistenten Herrn Dr. Zeisel für die liebenswürdige Unterstützung, die sie mir während der Ausführnng meiner Arbeit angedeihen liessen, meinen warmsten Dank auszusprechen.     

Über die Elemente der Yttergruppe

Ohne Zusammenfassung     

Cationic,Methylene‐Bridged,Intramolecular Donor‐Acceptor Systems Based on Zirconium and Hafnium and Phosphino‐methanides

A new access to cationic zirconium and hafnium compounds [L₂MCH₂PR₂][MeB(C₆F₅)₃] (L = Cp, Ind; R = iso‐Pr, tert‐Bu; M = Zr, Hf) exhibiting an intramolecular donor‐acceptor system was established by treating the precursors L₂M(Me)CH₂PR₂ with B(C₆F₅)₃ (BCF). Precursors 1 – 6 [L₂M(Me)CH₂PR₂ with L = Cp, Ind; R = iso‐Pr, tert‐Bu; M = Zr, Hf] were fully characterized. The crystal structures of these compounds revealed large M–CH₂–P bond angles with values of about 134° indicating the absence of interactions between the Lewis‐acid and Lewis‐base. The cationic compounds [L₂MCH₂PR₂][MeB(C₆F₅)₃] ( 7 – 12 ) were obtained by treatment of 1 – 6 with BCF. They were characterized by NMR spectroscopy, mass spectrometry, and elemental analyses; in H/D‐scrambling experiments with H₂/D₂ mixtures 7 – 12 disclosed their reactivity towards cleavage of hydrogen.     

Viscoelastic properties of confined molecular layers

We study the viscoelastic properties of a film of n layers of spherical molecules confined between two walls. We find that the dynamic response arises from two competing contributions: the effective stiffness of n + 1 springs in series and softening due to strain fluctuations. In particular, the latter are the origin of the oscillatory behavior of the stiffness and the damping coefficient. The dissipation is strongest at the minima of the stiffness; the inverse behavior may occur for a modulated relaxation time. As a corollary we show that confined molecular layers cannot be described as Maxwell fluids.     

Stabilization of the radial equilibrium of a tethered satellite with respect to out-of-plane initial perturbations

We investigate the stabilization of the radial equilibrium of a tethered satellite by tension control, if both in-plane and out-of-plane deviations from the vertical position are taken into account. While in-plane perturbations can be eliminated in finite time, the length rate change of the tether acts as parametric control on the out-of-plane deviations. Therefore the control becomes less effective, if the perturbation decreases. In order to improve the convergence we investigate the optimal control problem assuming no costs for the applied tension force but restricting the control force to a finite interval. For tether cconfigurations close to the vertical target position this approach yields a solution with singular control, which leads to a faster decay of the deviations. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

The dynamics of brand equity: a hedonic regression approach to the laser printer market

The authors develop a dynamic hedonic regression approach to measuring the evolution of a comparative brand premium (pairwise price difference between two products that are identical in all respects apart from the brand). In contrast to existing approaches, the proposed Bayesian estimation method exploits the premia's intertemporal dependence structure, resulting in a higher level of accuracy of the estimated time paths of the brand premia. In addition, the authors present a novel, but straightforward way to construct confidence bands that cover the entire time series of brand premia with high probability. The authors apply their approach to a large, detailed data set on laser printers, which was gathered on a monthly basis over a 4-year period.