Rock fall analysis in an Alpine area by using a reliable integrated monitoring system: results from the Ingelsberg slope (Salzburg Land,Austria)

The present work illustrates the monitoring system of the Ingelsberg slope (Bad Hofgastein, Austria), which hosts one of the most dangerous landslides in the Salzburg Land. It is a rock fall, which can be considered as representative of landslides commonly occurring in the Alpine area. During the monitoring campaign (March 2013–July 2014), a rock fall occurred at the end of April, 2013 that involved 20–40 m³ of rocks. The comparison of surface measurements (by Ground-Based Interferometric Synthetic Aperture Radar—GB-InSAR) with measurements in depth (by extensometers) allowed the understanding of the failure process of the rock mass. Data are discussed taking into account meteorological conditions antecedent to the landslide triggering, indicating that factors such as rapid snow melting (added to first spring rainfall events) and rock thermal dilatation are very important in slopes located far below the permafrost line.     

Catalytic partial oxidation of n-octane and iso-octane: Experimental and modeling results

The Catalytic Partial Oxidation (CPO) of two octane isomers, 2,2,4-trimethyl pentane (iso-octane) and n-octane, chosen as representative of gasoline is investigated by means of adiabatic tests and mathematical modeling. CPO experiments were carried out in a lab scale auto-thermal reformer with honeycomb monolith catalysts (2% Rh/α-Al₂O₃), equipped with probes for spatially resolved measurements of temperature and concentration. Tests were performed with about 50% N₂ dilution to prevent risks of deactivation due to catalyst over temperature. The CPO of the two isomers follows similar reaction pathways, which mainly consist of the exothermic combustion reaction and the endothermic steam reforming. This results in a close similarity of the concentration profiles of the main species and of the temperature profiles obtained with the two isomers. On the other hand, gas phase reactions proceed to a different extent and bring about a different distribution of thermal cracking products, iso-octane being more reactive and selective to iso-butylene and propene, while n-octane being selective to ethylene. Coke formation was observed upon adiabatic tests which was responsible for partial deactivation of the reforming zone of the catalyst. Post mortem TPO tests show that n-octane exhibits a higher tendency to coke deposition than iso-octane in the adopted CPO conditions. Thermodynamic and modeling calculations show that the risk of coking can be reduced by using exhaust gas recycling instead of N₂ to dilute the reactants.     

Deep neural networks and mixed integer linear optimization

Deep Neural Networks (DNNs) are very popular these days, and are the subject of a very intense investigation. A DNN is made up of layers of internal units (or neurons), each of which computes an affine combination of the output of the units in the previous layer, applies a nonlinear operator, and outputs the corresponding value (also known as activation). A commonly-used nonlinear operator is the so-called rectified linear unit (ReLU), whose output is just the maximum between its input value and zero. In this (and other similar cases like max pooling, where the max operation involves more than one input value), for fixed parameters one can model the DNN as a 0-1 Mixed Integer Linear Program (0-1 MILP) where the continuous variables correspond to the output values of each unit, and a binary variable is associated with each ReLU to model its yes/no nature. In this paper we discuss the peculiarity of this kind of 0-1 MILP models, and describe an effective bound-tightening technique intended to ease its solution. We also present possible applications of the 0-1 MILP model arising in feature visualization and in the construction of adversarial examples. Computational results are reported, aimed at investigating (on small DNNs) the computational performance of a state-of-the-art MILP solver when applied to a known test case, namely, hand-written digit recognition.     

High resolution magic angle spinning MRS in prostate cancer

Magnetic Resonance Materials in Physics, Biology and Medicine - Prostate cancer (PCa) is one of the leading causes of death among men worldwide. The current methods utilized to screen for prostate...     

Role of elongational viscosity of feedstock in extrusion-based additive manufacturing of powder-binder mixtures

The 3D printing of metals and ceramics by the extrusion of a powder/thermoplastic binder feedstock is an extrusion-based additive manufacturing (EAM) techn     

The effect of silylation on titanium-containing silica catalysts for the epoxidation of functionalised molecules

The epoxidation of functionalised substrates of interest as fine chemicals using mesoporous titanium-containing silicas is here reported and the role of silylation in changing the surface hydrophilic character of these catalysts is investigated. The silylation procedure was carried out on two titanium-grafted silicas with different morphologies. An ordered MCM-41 and a non-ordered commercial mesoporous silica were used as supports. The reactivity of bulky substrates with different characteristics (limonene, -terpineol, carveol and methyl linoleate) is studied and compared. The effect of silylation is more pronounced on Ti–MCM-41 than with low-surface area Ti–SiO₂ and it is shown that the catalytic performances are strongly dependent on the nature of the reactant. Purely alkenic molecules show better reactivity over silylated catalysts than over non-silylated ones. On the other hand, a hydrophilic environment around the titanium active sites has often a beneficial effect in the epoxidation of richly functionalised substrates.     

A temperature programmed desorption study of the interaction of acetic anhydride with zeolite beta (BEA)

The interaction of acetic anhydride with the Na- and H-forms of zeolite BETA, as well as with materials where copper or iron has been introduced into BEA by ion exchange, has been studied by temperature programmed desorption (TPD). In all cases acetic acid is a main desorption product in the temperature range 370–570 K. Ketene desorption is also significant, although it is argued that much of it is retained in the zeolite pores, where it undergoes further decomposition into carbon monoxide, hydrogen and water. There is an inverse correlation between the quantity of ketene desorbed and the activity of the catalysts in the catalytic acylation of anisole by acetic anhydride to yield p-methoxyacetophenone. The significance of this observation is discussed and an acylation mechanism involving ketene is proposed.