Research Data Repository of Saxon Universities
OPARA is the Open Access Repository and Archive for Research Data of Saxon Universities.
Researchers of Saxon Universities can either publish their research data on OPARA, or archive it here to comply with requirements of funding acencies and good scientic practice, without public access.
You can find the documentation of this service at the ZIH Data Compendium websites. If you need suppourt using OPARA please contact the Servicedesk of TU Dresden.
Please note: The OPARA service was recently upgraded to a new technical platform (this site). Previously stored data will not be available here immediately. It can be found at the still active old version of OPARA. These stock data will be migrated in near future and then the old version of OPARA will finally be shut down. Existing DOIs for data publications remain valid.
Communities in OPARA
Select a community to browse its collections.
Recent Submissions
X-ray CT Data of Lunar Regolith Simulants and Gray Value Sensitive Simulation Data
(Technische Universität Bergakademie Freiberg, 2026-02-18) Ditscherlein, Ralf
This dataset provides reconstructed X-ray microtomography data of four lunar regolith simulants together with simulated data for method evaluation. The dataset enables reproducibility of the particle fingerprint visualization technique, supports exploration of imaging artifacts, and provides reference implementations in Python. It is intended for use in particle system characterization, image analysis, and method benchmarking.
Magnetic suscptibility classes of WEEE slag and Norra Kärr Ore
(Technische Universität Bergakademie Freiberg, 2026-02-17) Siddique, Asim; Leißner, Thomas
This dataset contains particle-scale mineralogical and magnetic characterization data of particulate materials relevant to magnetic separation in mineral processing. It was developed to enable quantitative assessment of magnetic susceptibility variability at both class and particle scales and to support geometallurgical analysis of separation behavior. The dataset integrates experimental magnetic classification, bulk magnetic susceptibility measurements, and SEM-based automated mineralogical analysis.
The data were generated from two contrasting material systems: a natural ore (Norra Kärr) and a secondary resource derived from Waste of Electrical and Electronic Equipment (WEEE) slag. For the natural ore, two particle size fractions were investigated (500–1000 µm and 125–250 µm), while for the WEEE slag a finer particle size fraction (63–100 µm) was analyzed. This combination of materials and size fractions allows evaluation of magnetic heterogeneity across different mineralogical complexities and processing-relevant conditions.
Components of the Dataset
Magnetic Susceptibility Classification Data:
• Particles were separated into discrete magnetic susceptibility classes using a Frantz Isodynamic Separator by systematically varying the applied magnetic field strength under controlled chute conditions.
• Each susceptibility class represents a population of particles with comparable magnetic response.
Bulk Magnetic Susceptibility Measurements:
• For each magnetic susceptibility class, bulk magnetic susceptibility was measured using a magnetic susceptibility balance.
• Multiple sub-samples and repeated measurements were performed per class to improve representativity and reduce measurement uncertainty.
• The resulting values provide class-average magnetic susceptibility used as reference data.
SEM-Based Automated Mineralogy (MLA) Data:
• Quantitative mineralogical characterization of each magnetic susceptibility class was performed using Mineral Liberation Analysis (MLA).
• The data include modal mineral phase proportions for each susceptibility class.
• Particle-by-particle mineralogical compositions were extracted, providing phase fractions and mineral associations at the individual particle scale.
Metadata and Experimental Context:
• The dataset includes metadata describing particle size fractions, magnetic separation conditions, measurement procedures, and material context.
• This information enables reproducibility and supports reuse of the data in comparative or methodological studies.
The dataset enables analysis of relationships between mineralogical composition and magnetic response, estimation of particle-scale magnetic susceptibility, and assessment of magnetic heterogeneity in mineral feeds. It is suitable for applications in magnetic separation studies, geometallurgical analysis, particle-based mineral processing research, and the development or validation of data-driven characterization methods. Users should note that MLA-derived mineralogical data are based on two-dimensional polished sections and may be subject to stereological effects.
GRK 2802: MgO-C REFRACTORIES BASED ON REFRACTORY RECYCLATES AND ENVIRONMENTALLY FRIENDLY BINDERS
(Technische Universität Bergakademie Freiberg, 2026-02-16) Stadtmüller, Till Manon Jannis; Storti, Enrico; Brachhold, Nora; Lauermannová, Anna-Marie; Jankovský, Ondřej; Schemmel, Thomas; Hubálková, Jana; Gehre, Patrick; Aneziris, Christos
This study focused on the development of an environmentally friendly binder system based on lignin and collagen for uniaxial pressed MgO-C refractories as an alternative to commonly used resin or pitch binders. Additionally, recycled MgO-C refractories from steel plants were partially utilized as raw material, investigating their influence on the resulting physical and mechanical properties. The binder system showed reliable binding properties, although the recyclate-containing MgO-C exhibited higher porosity, slightly lower density, and lower strength compared to the reference batches without recyclates. However, antioxidants significantly improved the properties of the recyclatecontaining MgO-C samples. Scanning electron microscopy analysis with energydispersive X-ray spectroscopy revealed the formation of whiskers, as well as oxidation and nitridation of aluminum particles. This research highlights the potential of environmentally friendly binders and the utilization of recycled materials in MgO-C refractories to mitigate their environmental impact and enhances the environmental performance of carbon containing refractory materials.
GRK 2802: IMPROVEMENT OF THE PROCESSABILITY AND THE PROPERTIES OF LIGNIN AND COLLAGEN BONDED MGO-C REFRATORY MATERIALS BY ETHYLENE GLYCOL ADJUSTMENT
(Technische Universität Bergakademie Freiberg, 2026-02-16) Stadtmüller, Till Manon Jannis
This study systematically investigates the influence of the ethylene glycol content on the physical properties of lignin- and collagenbonded MgO-C refractory materials, particularly the compressibility, density, and porosity. The results show that an ethylene glycol content of 1.5 wt.% results optimal material properties, achieving the highest geometric bulk density, lowest open porosity, and maximum cold crushing strength of the experimental series. This work highlights the crucial role of the moisture content on the processability and its impact on the mechanical properties of the final product. The findings provide valuable insights into optimizing the binder systems of MgO-C materials, leading to improved production processes and enhanced performance in hightemperature applications.
GRK 2802: Pre‐oxidized Recycled MgO–Steel Composite Material for Possible Application in Cryolitic Melts
(Technische Universität Bergakademie Freiberg, 2026-02-16) Yaroshevskyi, Serhii; Brachhold, Nora; Malczyk, Piotr; Gehre, Patrick; Aneziris, Christos
Recycled MgO–C lining bricks and 316L stainless steel are used to manufacture composite material for inert anode samples for aluminum electrolysis cell. The microstructure of the composite material is characterized after preoxidation thermal treatments at 800, 900, and 1000 °C as well as in its sintered state. Preoxidation (PO) process is designed to enhance the material's corrosion resistance in molten cryolite environments by developing robust Fe–Mg–O, Fe–Cr–O- containing phases. Analytical techniques including scanning electron microscopy, electron backscatter diffraction, and energy dispersive X-ray spectrometry are applied to characterize the phase formation, revealing the potential of these composites for use as inert anodes in aluminum electrolysis cells. PO at 800 °C is not sufficient to form adequate protective oxide layers. Whereas, PO at 900 and 1000 °C leads to the formation of protective oxide layers containing Mg–O Fe–O halite-like solid solutions and (Cr,Fe)3O4 spinel phase. Sample, preoxidized at 1000 °C is sealed in Mg–Fe–O spinel phase.