Gold- and platinum induced nanowires on Ge(001); structure, electronic properties and interactions with simple molecules

The ongoing miniaturization of (components of) electronic devices will\ud eventually need a totally new preparation route for these (components of)\ud devices. It is thought that the ultimate miniaturization requires the use of\ud functional molecules and their incorporation into nanostructured templates.\ud For that reason it is interesting to study nanostructured surfaces and the\ud behaviour of adsorbed molecules on these surfaces.\ud In this dissertation results are described on two different nanostructured\ud surfaces. Their structural and electronic properties were studied with\ud scanning tunneling microscopy (STM) and scanning tunneling spectroscopy\ud (STS)

Using Artificial Neural Networks to Determine Ontologies Most Relevant to Scientific Texts

This paper provides an insight into the possibility of how to find ontologies most relevant to scientific texts using artificial neural networks. The basic idea of the presented approach is to select a representative paragraph from a source text file, embed it to a vector space by a pre-trained fine-tuned transformer, and classify the embedded vector according to its relevance to a target ontology. We have considered different classifiers to categorize the output from the transformer, in particular random forest, support vector machine, multilayer perceptron, k-nearest neighbors, and Gaussian process classifiers. Their suitability has been evaluated in a use case with ontologies and scientific texts concerning catalysis research. From results we can say the worst results have random forest. The best results in this task brought support vector machine classifier

Sprunggelenksfrakturen im Alter:klinische Studie zum Vergleich der operativen Therapie bei jungen und älteren Patienten

Instabile Sprunggelenksfrakturen werden bei jüngeren Patienten standardmäßig operiert, während dies bei älteren Patienten kontrovers diskutiert wird. Es wurden die operativen Ergebnisse von 28 älteren Patienten über 65 Jahren mit instabilen Sprunggelenkfrakturen mit denen von 66 jüngeren Patienten unter 65 Jahren anhand des AOFAS Scores sowie weiteren Parametern verglichen. Im Durchschnitt erreichten die jüngeren Patienten mit 92,4 von 100 Punkten im AOFAS Score ein sehr gutes klinisches und signifikant besseres Resultat als die älteren Patienten. Diese erzielten mit 86,4 Punkten ein gutes Resultat.Risikofaktor für ein schlechteres Ergebnis bei älteren Patienten ist das Erleiden einer Trimalleolarfraktur. Bei jüngeren Patienten verschlechterten ein früher OP-Zeitpunkt, späte Mobilisation und eine pAVK das Ergebnis signifikant.Insgesamt ist eine operative Versorgung instabiler Sprunggelenkfrakturen bei älteren Patienten aufgrund guter postoperativer Resultate erstrebenswert

Local probing of coupled interfaces between two-dimensional electron and hole gases in oxide heterostructures by variable-temperature scanning tunneling spectroscopy

The electronic structure of an epitaxial oxide heterostructure containing two spatially separated two-dimensional conducting sheets, one electronlike (2DEG) and the other holelike (2DHG), has been investigated using variable temperature scanning tunneling spectroscopy. Heterostructures of LaAlO3/SrTiO3 bilayers on (001)-oriented SrTiO3 (STO) substrates provide the unique possibility to study the coupling between subnanometer spaced conducting interfaces. The band gap increases dramatically at low temperatures due to a blocking of the transition from the conduction band of the STO substrate to the top of the valence band of the STO capping layer. This prevents the replenishment of the depleted electrons in the capping layer from the underlying 2DEG and enables charging of the 2DHG by applying a negative sample bias voltage within the band gap region. At low temperatures the 2DHG can be probed separately with the proposed experimental geometry, although the 2DEG is located less than 1 nm belo

Chapitre 8 - Contribution du système de développement agricole à la dynamique de l’agronomie

Le développement agricole caractérise généralement un processus de transformation de l’agriculture se situant au carrefour entre la recherche et la formation, lieux de création de connaissances théoriques, génériques, et l’agriculture, lieu de leur mise en application à la diversité des situations locales. En France, depuis la fin de la Seconde Guerre mondiale, les activités de développement agricole soutenues par les pouvoirs publics sont portées par un ensemble d’acteurs au service d’un pr..

Removal of submicron particles from solid surfaces using surfactants

The removal of nano- or submicron particles from solid substrates is of considerable interest in a range of existing industries including cleaning of surfaces inside a spacecraft after evaporation of nanofluids. A method of nanoparticle removal using aqueous surfactant solutions is proposed. The surfactants' cleaning efficiency is investigated for all four combinations of hydrophilic (HL) and hydrophobic (HB) nanoparticles and surfaces, in order to find the most successful cleaning method in each combination. Carbon and silica nanoparticles deposited onto Teflon and glass surfaces were used. Cationic, anionic and non-ionic surfactants with a range of CMCs and HLBs were used in order to identify the best surfactant in each scenario

Numerical study of the coupling between reaction and mass transfer for liquid-liquid slug flow in square microchannels

While the benefits of miniaturisation on processes have been widely demonstrated, its impact on microfluidics and local mechanisms such as mass transfer is still little understood. The aim of this work is to simulate coupling between reaction and mass transfer in microchannels for liquid-liquid slug flow. First, the extrapolation to confined flow of the classical model used to calculate interfacial mass fluxes in reactive infinite media was studied. This model consists in estimating transferred fluxes between two phases as a function of the enhancement factor E. Its expression depends on the model used to represent interfacial mass transfer. In infinite media, Lewis and Whitman’s stagnant film theory is generally preferred for its simplicity and its reliability. In the case of confined slug flow, the limitation of such a model to predict interfacial fluxes is highlighted. Secondly, the case of liquid-liquid competitive consecutive reactions in microchannels is considered. This work emphasizes the unfavourable impact of the length between droplets on selectivity. This is a direct consequence of mass transport mechanisms in microchannels