Quantifying of a dynamic refractory wear test setup for MgO-C products

The induction furnace test is one of the most common used refractory wear testing methods for MgO-C products. Due to the high oxidation rates in the ITO test setup and the significant changes in slag chemistry the test method sometimes gives results which cannot be compared to the field. For a general “Yes or No” decision this test is suitable for testing MgO-C refractories, determination of small differences in performance of MgO-C products, which is especially important for the development of new grades, is hardly possible. Due to that the application of a supplementary testing method was tested at the Chair of Metallurgy (Montanuniversitaet Leoben).     

BASF NanoSelect? Technology: Innovative Supported Pd- and Pt-based Catalysts for Selective Hydrogenation Reactions

An innovative BASF catalyst manufacturing technology (NanoSelect?) is introduced which allows production of heterogeneous catalysts with excellent control over metal crystallite sizes. NanoSelect? technology enabled the development of Pd catalysts which are lead-free Lindlar catalyst replacements in alkyne-to-cis-alkene hydrogenations. NanoSelect? Pt catalysts showed excellent chemoselectivity in substituted nitro-arene hydrogenation reactions without build-up of hydroxylamine intermediates. All NanoSelect? produced catalysts show markedly higher activity per gram of metal leading to ten-fold less use of precious metal.     

Cost-benefit analysis for disruption prevention in low-volume assembly

Manufacturing companies face rising pressure due to increased competition. Traditionally, companies have merely concentrated on offering impeccable, cost-efficient products. Today, however, flexibility and on-time delivery are additional requirements to satisfy the customers. At the same time, disruptions in production, especially in low-volume assembly, still frequently occur, leading to economic losses and delayed customer deliveries. The approach proposed in this paper strives for improving the disruption situation in low-volume assemblies. A detailed disruption management methodology has been developed, aiming at realizing an efficient reduction of disruptions, while at the same time considering the specific characteristics of low-volume assembly. The methodology is supported by a catalog of pre-emptive measures. These measures are known to reduce the disruptions’ occurrence or to diminish their consequences. In general, the approach pursues the basic idea to implement particularly those measures, which have the best cost-benefit-ratio. Based on the analysis of the cost-benefit-ratio of each measure, the developed methodology aims at improving the disruption situation in assembly and thus providing a high on-time delivery rate. The usability of the methodology for the low-volume assembly context has been confirmed by assembly experts on the basis of an application of the methodology in an exemplary case study.     

Development and Performance of Crystallization with Additives Applied on Different Milk Samples

Crystallization with additives is developed on milk samples from different processing treatments. Performance tests are carried out based on structure analysis of the crystallization patterns. Crystallization with milk as additive is applied following changes in milk after different processing treatments. When an aqueous cupric chloride dihydrate solution crystallizes in the presence of milk as additive, specific patterns emerge, which can be evaluated by image analysis. Milk samples were heated and homogenized in a pilot plant and characterized by various parameters. Furthermore, milk samples from the market were tested. Patterns from milk after heat treatment and homogenization are significantly different from those derived from untreated milk. The experiments could be reproduced for other milk samples, on different days and in another laboratory.     

Design and analysis of UW-OFDM signals

Unique word-orthogonal frequency division multiplexing (UW-OFDM) is a novel signaling concept where the guard interval is implemented as a deterministic sequence, the so-called unique word. The UW is generated by introducing a certain level of redundancy in the frequency domain. Different data estimation strategies and the favourable bit error ratio (BER) performance of UW-OFDM, as well as comparisons to competing concepts have already extensively been discussed in previous papers. This work focuses on the different possibilities on how to generate UW-OFDM signals. The optimality of the two-step over the direct approach in systematic UW-OFDM is proved analytically, we present a heuristic algorithm that allows a fast numerical optimization of the redundant subcarrier positions, and we show that our original intuitive approach of spreading the redundant subcarriers in systematically encoded UW-OFDM by minimizing the mean redundant energy is practically also optimum w.r.t. transceiver based cost functions. Finally, we derive closed form approximations of the statistical symbol distributions on individual subcarriers as well as the redundant energy distribution and compare them with numerically found results.     

Hydraulic linkage of a storm water tank to a karst spring (Gallusquelle)

Grundwasser - A significant proportion of the global water supply is ensured by karst aquifers. However, these are often highly vulnerable to contamination. A storm water tank...     

Transport mode preferences,risk perception and worry in a Norwegian urban population

The main aim of the present study was to compare risk perception among Norwegians (n = 512) living in the region of Oslo. This study was part of an ERANET 13 project entitled PETRIS, Perception of transport risk in France and Norway. The data collection was carried out in January 2011. The response rate was 51 percent. The results showed that respondents, divided in two groups according to their transport mode preferences, assessed differently risk perception in public and private transportation. Respondents who preferred collective transportation assessed the probability of experiencing criminality in collective transport modes as higher than those who preferred private modes. They were also more worried of experiencing accidents, criminality, and terror attacks in collective transportation. The relationship between transport mode preferences and use, risk perception and worry are discussed.     

Aqueous‐Phase Reforming in a Microreactor: The Role of Surface Bubbles

In heterogeneous catalysis, the creation of gaseous products as bubbles in a liquid phase on the catalytic surface is associated with slip phenomena. In a microreactor, the slip length at the gas‐liquid interface is in the same order of magnitude as the reactor dimensions, which can affect fluid dynamics and transport phenomena. Here, the interplay of momentum, heat and mass transfer in a microreactor, when bubbles form on the catalytic surface, was investigated using two‐dimensional simulations. The effect of bubbles on the endothermic process of aqueous‐phase reforming of a glycerol solution was evaluated in terms of conversion and conversion and temperature in the reactor. Altogether, this study highlights the impact of bubbles, not only on the transport phenomena but also on the reactor performance.