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Düsseldorf, Germany

A characterization of the classical Noctuidae sensu Hampson, Boursin, Hartig & Heinicke, Nye and Poole is achieved by considering larval morphology. Larval characters indicate that the Noctuidae sensu Hampson and the Nolidae sensu stricto sensu Hampson are monophyletic. Comparison of the setal maps of the larvae of Tyria jacobaeae (Hübner) and Jocheaera (Apatele auct.) alni (Linnaeus) with the common chaetogram of the Noctuidae demonstrate this, and suggest, as already supposed from imaginal systematics, that the Arctiidae are the sister-family of the Noctuidae. The choice of unsuitable imaginal character systems plus the failure to include suitable features of the immature stages and especially the wrong interpretation of reversals and the acceptance of using them (as part of a new holomorphis of a quite different taxon) have resulted in the present unsatisfying situation of the higher classification of the Noctuoidea, especially of the Noctuidae.- A larval characterization of the classical Nolidae sensu stricto, sensu Hampson is given. This precludes any combination between these Nolidae and the Noctuidae sensu Hampson. The capacity of phylogenetical systematization is complicated by reversals or limited by them if they will not be used as characters of a completely different and modern taxon (as compared with the "plesiomorphic" more ancient one). Source

Santa M.,Max Planck Institute Fur Eisenforschung | Posner R.,Max Planck Strasse | Posner R.,Ohio State University | Grundmeier G.,Max Planck Strasse | Grundmeier G.,University of Paderborn
Journal of the Electrochemical Society | Year: 2011

Low carbon steel substrates were covered with a γ -glycidoxypropyltrimethoxysilane (γ -GPS) modified epoxy layer. Electrochemical impedance spectroscopy and attenuated total reflection infrared spectroscopy were used to investigate the barrier properties of the coating. The resistance of the samples to ion transport processes along the epoxy/steel interface was determined by in situ scanning Kelvin probe (SKP) measurements of the interface potential. X-ray photoelectron spectroscopy studies helped to analyze the resulting ion distribution on the substrate surface. The application of γ -GPS resulted in a reduction of the interfacial water activity and temporarily stabilized the polymer/steel interface. In contrast to the experiments with the unmodified epoxy coating, interfacial ion transport processes were verifiable with the SKP. After some days of sample exposure to humid air, the stabilizing effect of γ -GPS diminished and SKP potential profiles had to be recorded in dry atmosphere to identify the electrolyte front position, zones of cation and anion separation, and areas of local corrosion damage at the interface. This approach seems to be generally promising to analyze the degradation state of polymer/oxide/metal interfaces after long-term exposures in humid air. © 2010 The Electrochemical Society. Source

Posner R.,Max Planck Institute Fur Eisenforschung | Posner R.,Ohio State University | Santa M.,Max Planck Strasse | Grundmeier G.,Max Planck Institute Fur Eisenforschung | Grundmeier G.,University of Paderborn
Journal of the Electrochemical Society | Year: 2011

Steel substrates were coated with a water-borne epoxy polymer layer and investigated by in situ scanning Kelvin probe (SKP) experiments, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and peel tests. After ion transport processes along the polymer/substrate interface were initialized at an electrolyte covered coating defect, nonspecific potential profiles were detected with the SKP. An identification of the front position of the electrolyte was not possible in air of high relative humidity, because wet de-adhesion and hydrolysis processes determined the local interface potential. Although the established mechanistic model for cathodic delamination solely predicts a cation transport in humid air, anions of the defect electrolyte were also verifiable at the epoxy/steel interface. It is discussed which forces rather than ion diffusion were additionally effective and contributed to the overall driving forces for the ion transport in this case. The oxidation state of the resulting substrate structure was investigated to further analyze the epoxy/steel interface degradation. These results are compared to the initial surface condition of the uncoated steel surface. They are also compared to the surface condition after oxygen reduction induced electrolyte spreading proceeded along the uncoated steel substrate. © 2010 The Electrochemical Society. Source

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