OPARA Research Data Repository of Saxon Universities
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Farnesischer Stier - Bodenplatte unter Amphion, Universität Leipzig, Antikenmuseum, G 661 - TF 1, high-poly
No full textDieser Datensatz enthält das High-Poly-Modell der Bodenplatte unter Amphion aus der Gipsabformung der Skulpturengruppe des Farnesischen Stiers, die sich im Antikenmuseum der Universität Leipzig (Inventarnummer G 661, TF 1) befindet. Das 3D-Modell basiert auf den hochaufgelösten Rohdaten und wurde durch Polygonreduktion optimiert. Dabei blieb die geometrische und visuelle Qualität erhalten, während die Dateigröße deutlich reduziert wurde
Data for "Dirac quantum criticality in twisted double bilayer transition metal dichalcogenides"
No full textThe archive contains the data used to construct Figs. 2-6 and 8 of the paper "Dirac quantum criticality in twisted double bilayer transition metal dichalcogenides" by Jan Biedermann and Lukas Janssen [arXiv:2509.04561]. The work uses self-consistent Hartree-Fock calculations to compute the phase diagram of twisted double bilayer transition metal dichalcogenides as a function of the twist angle and applied pressure
GRK 2802: Extraction of Vanadium from CaO–SiO2–MgO–Al2O3 Slags Based on Vaporization of Vanadium Pentoxide
No full textVanadium is an important micro-alloying element for various steel grades. Consequently, it is also present in the slags used in the production of those grades. During steelmaking, the vanadium vaporization from the slag is not desirable, as it increases vanadium consumption and at the same time releases toxic vapors of its higher oxides. However, the recovery of vanadium from the slag after the processing is worthwhile. In oxidic form as vanadium pentoxide (V2O5), vanadium can be extracted from the slag. In this research, the vaporization behavior of vanadium from CaO–SiO2–MgO–Al2O3 industrial slag is investigated at 1873 K. The effect of different process parameters, e.g., the pressure in the furnace chamber, the duration of the oxygen treatment of the slag, and the oxygen flow rate, is considered. The effect of P2O5 and Fe2O3 addition on the extraction of vanadium is studied. It is possible to induce formation of V2O5 gas bubbles in the slag due to the oxidation of vanadium. Thus, vanadium respectively V2O5 is extracted from the slag
Data for "An Elephant Under the Microscope: Analyzing the Interaction of Optimizer Components in PostgreSQL"
No full textThis dataset presents benchmark data for the SIGMOD 2025 publication "An Elephant Under the Microscope: Analyzing the Interaction of Optimizer Components in PostgreSQL" (https://doi.org/10.1145/3709659).
The dataset spans multiple different experiments, each analyzing how different components of relational query optimizers influence each other and how they perform when faced with faulty input.
For each experiment a dedicated ZIP file is available. These files contain READMEs with technical information (e.g. table columns).
Detailed descriptions of the individual experiments can be found in the actual publication, as well as in the code repository that provides the actual experiment scripts for reproducibility (available at https://github.com/db-tu-dresden/SIGMOD25-PostgreEval)
Data corresponding to the publication "Optical and acoustic plasmons in the layered material Sr2RuO4"
No full textWe use momentum-dependent electron energy-loss spectroscopy in transmission to study collective charge excitations in the layer metal Sr2RuO4. This metal has a transition from a perfect Fermi liquid below T~30 K into a "strange" metal phase above T~800 K. We cover a complete range between in-phase and out-of-phase oscillations. Outside the classical range of electron-hole excitations, leading to a Landau damping, we observe well-defined plasmons. The optical (acoustic) plasmon due to an in-phase (out-of-phase) charge oscillation of neighbouring layers exhibits a quadratic (linear) positive dispersion. Using a model for the Coulomb interaction of the charges in a layered system, it is possible to describe the range of optical plasmon excitations at high energies in a mean-field random phase approximation without taking correlation effects into account. In contrast, resonant inelastic X-ray scattering data show at low energies an enhancement of the acoustic plasmon velocity due to correlation effects. This difference can be explained by an energy dependent effective mass which changes from ~ 3.5 at low energy to 1 at high energy near the optical plasmon energy. There are no signs of over-damped plasmons predicted by holographic theories
Data Underpinning: Correlated proton disorder in the crystal structure of the double hydroxide perovskite CuSn(OH)₆
No full textThis contains the data underpinning our paper on CuSn(OH)₆. The abstract of the article is reproduced here:
CuSn(OH)6 is a quantum spin system from the family of magnetic double perovskite hydroxides, having a frustrated magnetic sublattice. It is also known as the natural mineral mushistonite, whose crystal structure has remained elusive for decades. Here we employ x-ray and neutron powder diffraction to solve the crystal structure of CuSn(OH)6 and propose a structure model in the orthorhombic space group Pnnn with correlated proton disorder. The occupation of the hydrogen sites in the structure is constrained by “ice rules” similar to those known for water ice. The resulting frustration of the hydrogen bonding network is likely to have a complex and interesting interplay with the strong magnetic frustration expected in the face-centred magnetic sublattice. Structural distortions, which are quite pronounced in Cu2+ compounds due to the Jahn-Teller effect, partially alleviate both types of frustration. We also show that hydrostatic pressure tends to suppress proton disorder through a sequence of proton-ordering transitions, as some of the split hydrogen sites merge already at 1.75 GPa while others show a tendency toward possible merging at higher pressures
Data corresponding to paper: "Incorporation of a Viscoelastic-Elastoplastic Material Model for Asphalt based on the Multiscale Microlayer Model into an ALE Formulation for Pavement Structures Considering Dynamic Tire Loadings" by May et al. (submitted 2025)
No full textThis data publication contains the data related to the scientific contribution "Incorporation of a Viscoelastic-Elastoplastic Material Model for Asphalt based on the Multiscale Microlayer Model into an ALE Formulation for Pavement Structures Considering Dynamic Tire Loadings" by May et al. (submitted 2025).
Abstract of the corresponding paper:
During braking, acceleration, and steering maneuvers in road traffic, dynamic vertical loads are introduced into the pavement structure. These loads give rise to complex multiaxial stress states within the layered pavement structure, which consists of materials with differing mechanical behavior. The dynamic nature of these maneuvers requires that the resulting stress states have to be considered over large spatial and temporal intervals.
In this work, a novel multiscale ALE-FEM approach is introduced for the first time, capable of capturing the complex, multiaxial stress states within the asphalt pavement during steering and acceleration maneuvers. Numerical efficiency and physical representativeness are achieved through the use of a finite viscoelastic–elastoplastic material model embedded in the microlayer framework, a thermodynamically derived multiscale approach that avoids the computational cost of a conventional FE² scheme. Additionally, the application of a dynamic Arbitrary Lagrangian-Eulerian (ALE) formulation ensures that the meshed geometry remains small in comparison to the extensive length of the actually traversed road section.
To experimentally determine the loads generated by a tire during a steering maneuver, a single-wheel test rig is used, in which, the side slip angle is systematically varied. The measured data is then used to generate time- and space-resolved footprints, which serve as realistic boundary conditions for simulating tire pavement interaction
Photographic documentation of crack development on the openLAB during the loading test on 2025-05-06
No full textBetween 2025-05-05 and 2025-05-07, extensive experiments were carried out on the openLAB research bridge.
The test program was structured as follows:
- Day 1 (2025-05-05): Static and dynamic measurements in the reference state
- Day 2 (2025-05-06): Loading of the bridge with hydraulic jacks up to the ultimate limit state
- Day 3 (2025-05-07): Local damage to the prestressing tendons (cutting wires at several locations)
This dataset contains pictures of cracks in the precast element (PE) 2.1 during the load test conducted on day 2.
The load was applied locally to the prestressed element (PE) 2.1 (span 2, PE axis 1) using two hydraulic jacks and increased in steps up to a total of 400 kN.
The pictures were taken using a Dino-Lite AM4113T digital microscope connected to a laptop running the DinoCapture 2.0 software.
One set of pictures was taken for each load step, before applying the load and during the plateau of constant deflection (5 mm, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm)
Granule size and shape data from SOPAT for publication "Impact of Feed Rate and Binder Concentration on the Morphology of Spray Dried Alumina-Polymer Nano-composites"
No full textThis dataset comprises in-line experimental SOPAT data from spray drying investigations of alumina and polyvinylpyrrolidone-30 composite granules. The spray drying process outcomes are documented through inline optical images of dried granules obtained via a SOPAT in-line imaging system providing maximum and minimum Feret diameter and aspect ratio information
GRK 2802: Extra-carbonization of biochar pellets obtained after co-torrefaction and co-pyrolysis with bituminous coal
No full textThe paper investigates the chemical and structural changes in biochar pellets resulting from the co-torrefaction and co-pyrolysis of pine wood (Pinus sylvestris) pellets with bituminous coal at a 1:1 ratio at 300, 500, and 700 °C. At 500 °C co-pyrolysis, noticeable changes occur in biochar during co-treatment with coal, as observed by Fourier-transform infrared spectroscopy (FT-IR), graphite-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (GALDI-FT-ICR-MS), and Raman spectroscopy compared to individual pyrolysis. Proximate and ultimate analyses show an increase in carbon content and decreases in volatile matter, oxygen, and hydrogen in co-treated biochar pellets. FT-IR and van Krevelen plots indicate compounds with lower O/C ratios and fewer oxygen-rich functionalities. Raman spectroscopy shows that, at 300 and 500 °C, co-pyrolyzed biochar pellets have slightly more structural ordering and less disorder than biochar pellets from individual pyrolysis. This suggests that co-processing allows the creation of a more ordered aromatic carbon structure. GALDI-FT-ICR-MS indicates an increase in condensed aromatic hydrocarbons at the expense of lignin-like and oxygen-rich structures compared with individual pyrolysis. Specifically, 500 °C co-pyrolysis shifts biochar pellets composition toward lower O/C ratios (0–0.3); products are enriched in condensed aromatic hydrocarbons and occupy van Krevelen regions with low O/C (0–0.2) and H/C (0.4–0.8). The results demonstrate extra-carbonization effects in biochar pellets during co-pyrolysis with bituminous coal at 500 and 700 °C