Search
Now showing items 151-160 of 182
Aufsatz
The politics of energy landscapes: the influence of local anti-wind initiatives on state policies in Saxony, Germany
(2020-01-23)
Background
In recent years, landscapes in many countries have been transformed by efforts to fight global warming, specifically the shift towards renewable energies such as wind power. This development has been met by growing opposition from local citizens and their initiatives. There is an ongoing debate about whether and how such protests have a real impact on the development of energy landscapes.
Methods
Drawing on the rare case of a state government scaling back ambitious targets for the expansion of renewables, ...
Aufsatz
Access to the learning material enhances learning by means of generating questions: Comparing open- and closed-book conditions
(2020)
Generating questions referring to the learning material is a powerful learning strategy. The present study investigated potential mechanisms behind this effect. Students (N=231) read a text and then generated questions referring to the text in three conditions: (1) open-book (i.e., text accessible), (2) closed-book (i.e., text inaccessible), and (3) cued closed-book (i.e., text inaccessible but keywords provided). After one week, students’ knowledge gain was larger in the open-book and cued closed-book conditions ...
Aufsatz
Occurrence, distribution and alternative hosts of Wheat streak mosaic virus infecting ginger in Kaduna State, Nigeria
(2020-06-29)
A field survey was conducted during the 2018 rainy season (June – October) in three major ginger producing Local Government Areas (LGAs) of Kaduna State, Nigeria to determine the occurrence and spread of wheat streak mosaic virus (WSMV) infecting ginger. Symptomatic and asymptomatic ginger leaf samples (n=180) and weed samples (n=45) were collected from the surveyed fields and indexed against WSMV using Double Antibody Sandwich Enzyme-linked Immunosorbent Assay (DAS-ELISA). The results obtained showed that WSMV ...
Aufsatz
Typology of smallholder’s pig production systems in South Kivu, Democratic Republic of Congo: Challenges and opportunities
(2020-06-30)
Pig farming plays an important role in farmers’ livelihoods in many tropical countries. It contributes to food security of the poorest as well as the development of rural economy through multiplier effects. In the South Kivu province, pig farms are almost exclusively owned by smallholders. A few studies have attempted to describe thoroughly pig farming systems in this province. This study was undertaken to characterise pig production systems, in order to better understand their current situation, namely constraints ...
Aufsatz
On the influence of ϰ-carbides on the low-cycle fatigue behavior of high-Mn light-weight steels
(2021)
High-manganese light-weight steels offer a great potential for structural purposes in the mobility sector due to their reduced density combined with outstanding mechanical properties. As many of the envisaged applications of these materials will suffer from cyclic loading during their service life, the fundamentals of their fatigue behavior must be studied extensively. In the present work, the low-cycle fatigue (LCF) properties of an austenitic Fe-29.8Mn-7.65Al-1.11C light-weight steel were investigated. Two ...
Aufsatz
On the structural integrity of Fe-36Ni Invar alloy processed by selective laser melting
(2020)
Specimens made from pre-alloyed Invar (Fe-36Ni) powder were fabricated by selective laser melting and stress-relief heat treated afterwards. A relative density of the fabricated parts of 99.6 % was determined by computed tomography. The microstructure and mechanical behavior under monotonic and particularly cyclic loading at ambient temperature were investigated. Results reveal a bimodal microstructure containing columnar and equiaxed grains with an average grain size of 75 μm and pronounced texture 〈001〉 || BD. The ...
Aufsatz
Dynamic Tensile Deformation of High Strength Aluminum Alloys Processed Following Novel Thermomechanical Treatment Strategies
(2020-05-14)
Herein, the effects of a very recently introduced novel thermomechanical process route on the microstructural evolution and dynamic tensile deformation behavior of two different precipitation hardenable aluminum alloys, i.e., AA6082 and AA7075, are studied. The investigated materials are hot formed and quenched in differently tempered tools to reveal the influence of cooling rate. Microstructure analysis is conducted to study the influences of different cooling strategies on the microstructure evolution and prevailing ...
Aufsatz
Effect of Compositional Variation Induced by EBM Processing on Deformation Behavior and Phase Stability of Austenitic Cr-Mn-Ni TRIP Steel
(2020-01-24)
Electron beam melting (EBM) is an established powder bed-based additive manufacturing process for the fabrication of complex-shaped metallic components. For metastable austenitic Cr-Mn-Ni TRIP steel, the formation of a homogeneous fine-grained microstructure and outstanding damage tolerance have been reported. However, depending on the process parameters, a certain fraction of Mn evaporates. This can have a significant impact on deformation mechanisms as well as kinetics, as was previously shown for as-cast material. ...
Aufsatz
On the Impact of Texture and Grain Size on the Pseudoelastic Properties of Polycrystalline Fe–Ni–Co–Al–Ti Alloy
(2020-05-08)
The effects of thermomechanical treatments on crystallographic texture and grain size evolution and their impact on the pseudoelastic properties in Fe41–Ni28–Co17–Al11.5–Ti2.5 (at.%) were studied in the present paper. The results show that cold rolling leads to brass-type texture in this alloy, which is typical for low stacking fault energy materials. Thermal treatments up to 1300 °C were conducted and it is shown that the presence of β-phase helps to control grain growth. After the dissolution of the secondary phase ...
Aufsatz
Mittelalter erschließen
(2021-07-15)
Research communication has been gaining public attention in recent years. Therefore, medievalists also need to focus on the transfer of their research topics to the public both within and outside the university. Based on current political demands calling for a change in communication culture, the article first of all deals theoretically with two different concepts of research communication, by distinguishing between forms of translation and those of popularization. Numerous public events, exhibitions, and cooperative ...