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Rigorous full 3D modeling of coherence scanning interferometry and confocal microscopy [Dataset]
No full textIn order to validate a rigorous simulation model for confocal microscopes and coherence scanning interferometers, measurements were performed by a home-built Linnik interferometer (100x, NA=0.95) and a commercial confocal microscope (150x, NA=0.95). The dataset contains image stacks obtained by the Linnik interferometer for TE-, TM-, and unpolarized light. Additionally, the gratings reconstructed using a combination of envelope and phase analysis are included. In case of the confocal microscope, image stacks are not available, so only the reconstructed grating is stored. For further discussion, an AFM measurement result (tip radius 10 nm) is given as well. If you use the data please refer to our corresponding article mentioned below.LE 992/14-3LE 992/18-
Correlation of the crystalline structure, moisture content, texture and aging-induced degradation of polyamide 5.10 using wide-angle x-ray scattering analysis [Dataset]
No full textThis study provides a detailed analysis of the crystalline structure of polyamide 5.10 (PA5.10) and determines the effects of hydrothermal aging on its moisture content, crystallinity, and texture. Using wide-angle X-ray scattering (WAXS), the investigation revealed insights into both the amorphous boundary layer and the semi-crystalline core, with a Python script based on Bragg’s law enabling precise identification of crystalline phase planes. Gaussian fitting of crystalline peaks further refined the structural understanding. The effects of experimental parameters on WAXS measurements were examined to identify additional factors influencing PA5.10. Hydrothermal aging led to notable changes, including increased moisture absorption, volume expansion, enhanced crystallinity, and shifts in molecular structure and crystalline morphology. WAXS showed that moisture-induced scattering reduced intensity, which was reversible upon re-drying. Despite an increase in crystallinity observed by DSC, WAXS did not capture a corresponding shift, likely due to the combined effects of residual moisture and annealing processes. Overall, this study enhances the understanding of PA5.10's crystalline behavior under hydrothermal exposure and provides a basis for future investigations into its aging processes and structural evolution. These findings contribute to a broader understanding of the long-term degradation mechanisms and stability of bio-based polyamides under hydrothermal and humid conditions. Moreover, the insights gained are relevant for predicting material performance in moisture-sensitive applications and can inform the development of stabilization strategies for hygroscopic polymers.This dataset consists of the measured data from the conducted experiments, python scripts as well as the data analysis.In case you use the data please cite the corresponding article. The corresponding publication is currently in publication process.FNR, 2220NR089
Motion of water-immersed superparamagnetic microparticles on top of a topographically flat thin film substrate imprinted with engineered magnetic stripe domains of gradually increasing/decreasing stripe width and alternating head-to-head/tail-to-tail magnetization configuration
No full textThe controlled transport and fractionation of magnetic microparticles according to their structural and magnetic properties is of great importance for the realization of miniaturized Lab-on-a-chip devices, applicable, e.g., for medical point-of-care diagnostics. We designed a transport and pre-sorting system for superparamagnetic beads based on an engineered magnetic stray field landscape emerging from a magnetic stripe domain pattern inside an exchange-biased thin film system. The magnetic stripe domains were imprinted into the system via ion bombardment induced magnetic patterning. The pattern consists of stripe domains with gradually increasing and decreasing stripe width, periodically repeated across the whole substrate. Directed motion of superparamagnetic beads above the substrate inside a quiescent liquid (water) is induced by applying weak external magnetic field pulses, superposing the static magnetic stray field landscape. The beads are forced to perform a jumping motion with increasing/decreasing jump length owing to the arrangement of the underlying domain pattern. Our data shows a simultaneous fractionation of all particles into mobile and immobile units according to their magnetophoretic mobilities. The motion velocity of the particles is thereby a function of jump length (stripe domain width) and the magnitude of the external field pulses. Superparamagnetic beads of significantly different sizes can be spatially separated using a short sequence of constant field pulses.
Videos of the particle motion were recorded using high-speed cameras attached to an optical microscope. The water-dispersed particles were placed on top of the magnetically patterned substrate inside a microfluidic chamber and motion was initiated by applying periodically repeated magnetic field pulses (pulse lengths in the ms-range; pulse magnitudes in the mT-range) using orthogonally arranged Helmholtz coils. The videos were analyzed qualitatively and quantitatively (particle velocity) using a custom Python code.51485852443350169936137929236139616
Data selection strategies for minimizing measurement time in materials characterization, measurement data
No full textEvery new material needs to be assessed and qualified for an envisaged application. A steadily increasing number of new alloys, designed to address challenges in terms of reliability and sustainability, poses significant demands on well-known analysis methods in terms of their efficiency, e.g., in X-Ray diffraction analysis. Particularly in laboratory measurements, where the intensities in diffraction experiments tend to be low, a possibility to adapt the exposure time to the prevailing boundary conditions, i.e., the investigated microstructure, is seen to be a very effective approach. The counting time is decisive for, e.g., complex texture, phase, and residual stress measurements. Traditionally, more measurement points and, thus, longer data collection times lead to more accurate information. Here, too short counting times result in poor signal-to-background ratios and dominant signal noise, respectively, rendering subsequent evaluation more difficult or even impossible. Then, it is necessary to repeat experiments with adjusted, usually significantly longer counting time. To prevent redundant measurements, it is state-of-the-art to always consider the entire measurement range, regardless of whether the investigated points are relevant and contribute to the subsequent materials characterization, respectively. Obviously, this kind of approach is extremely time consuming and, eventually, not efficient. All relevant data including the code are carefully assessed and will be the basis for a widely adapted strategy enabling efficient measurements not only in lab environments but also large scale facilities. This data set consists of the fully measured data from the diffraction experiments as well as the manuscript for data analyzing.IMPORTANT: In case you use the data please cite our corresponding article: https://doi.org/10.1038/s41598-025-96221-1</p
Investigation of Synergistic Effects of UV Radiation and Elevated Temperatures on Regenerated Cellulose Fiber-Reinforced Bio-Polyamide 5.10 Composites and the Contribution of UV Stabilizers to their Stability [Dataset]
No full textThis study investigates the thermo- and photo-oxidative degradation behavior of a bio-based polyamide (PA) 5.10, both neat and 20 wt.% regenerated cellulose fiber-reinforced (RCF). In addition, these materials were modified with two different UV stabilizers, AddWorks IBC760 (IBC), a hindered amine light stabilizer, and LUBIO UV16 (LUBIO), an UV absorber. 168 hours of storage at temperatures of 23 °C, 50 °C, 70 °C to 90 °C at 50 %rH, with and without UV exposure of 1000 W/m², revealed significant degradation effects both in neat and LUBIO-stabilized batches, including molecular chain splitting processes, embrittlement, reduction in surface polarity and pronounced yellowing. In contrast, the IBC provided superior stabilization, maintaining thermal and mechanical properties as well as color stability. RCF-reinforced PA 5.10 exhibited moisture-induced plasticization, increasing ductility as well as aging-induced embrittlement at elevated temperatures. SEM imaging confirmed an increased share of fiber ruptures in the UV exposed neat RCF-composites, while IBC-stabilized specimens preserved the high amount of fiber pull-outs. Melt volume rate measurements demonstrate the reduction in molecular weight due to the thermo- and photo-oxidative degradation. A linear polynomial regression was also used to demonstrate the characteristic degradation mechanisms of polyamide. Overall, the IBC-stabilized batches show a significant stabilization effect across all tested storage conditions. These findings highlight the potential of UV-stabilized RCF-reinforced PA 5.10 composites as sustainable replacements for petro-based polyamide composites in applications requiring long-term resistance to thermo- and photo-oxidative stress.
This data set consists of the measured data from the conducted experiments as well as the data analysis.In case you use the data please cite the corresponding article. The corresponding publication is currently in publication process.FNR, 2220NR089
Assessing biodiversity of apricot landraces in Gilgit-Baltistan (Pakistan) using morphological and genetic traits (Microsatellite data)
No full textFor centuries, apricots (Prunus armeniaca L.) were used as a staple food in Gilgit-Baltistan (G-B), northern Pakistan where their high nutritional and medicinal value is still highly appreciated by many inhabitants. Here, many locally recognized landraces (referring to mainly undescribed varieties or cultivars) of apricot are available of which some are at risk of extinction, because of current human preferences replacing landraces by modern cultivars and other crop species. To assess the distribution, diversity, management and use of apricots in G-B, we made use of the region’s unique topography by employing the so-called ‘Dead-end valley sampling’ approach. It allowed to test the influence of market distance on morphological parameter classes. In 2021 and 2022, landrace richness, quantitative and qualitative morphological characteristics, and genetic diversity were investigated from 240 samples of several valleys. By employing 12 SSR markers we elaborated the identification of homonyms and synonyms of landraces. In addition, a total of 52 households from five valleys with three villages each as well as employees of two arboricultural research centres of Gilgit and Baltistan were interviewed.Among the sampled landraces, 120 different landraces were named by farmers of which Halman, Habi, Karfo chuli and Shikanda were most frequent. The highest Simpson index (0.96) was found in Ishkoman, the most western valley studied. The high average genetic diversity (He = 0.729) across three identified genetic clusters, was supported by high excess of heterozygotes, indicated by negative inbreeding coefficients. Across-valley β-diversity was 0.737. Correlation between phenotypic and genetic dendrograms was moderate (r = 0.45, p = 0.001) indicating genetically linked fruit traits, warranting further investigation. Due to its considerable genetic and phenotypic diversity, Gilgit-Baltistan constitutes an important reservoir of apricot germplasm for future breeding programs. Promoting local landraces—potentially even recognized as distinct varieties—could help farmers diversify production and income sources while preserving the region’s historically significant bio-cultural heritage. To realize this potential, conservation and management measures combined with stakeholder-driven research and controlled breeding initiatives for effective monitoring will be essential.ID 57569302
Transkript des dritten Projekttreffens 'Wie Bilder laufen lernten'
No full text<p>Der Datensatz stammt aus der Dissertation &bdquo;Das au&szlig;erunterrichtliche Lernangebot &sbquo;Kinder-Uni&lsquo; als Ressource f&uuml;r den Ausbau kindlicher Diskurskompetenz: Rekonstruktion explanativer diskursiver Praktiken in einem ausgew&auml;hlten Lehr-Lernarrangement f&uuml;r Sch&uuml;ler/innen der Primarstufe&ldquo;. Die gespr&auml;chsanalytisch orientierte Studie untersucht das Potenzial des au&szlig;erunterrichtlichen Lernangebots &sbquo;Kinder-Uni&lsquo; f&uuml;r die F&ouml;rderung diskursiver F&auml;higkeiten von Grundschulkindern, besonders im Kontext von Bildungsbenachteiligung bei Kindern mit Zuwanderungshintergrund. Analysiert werden Interaktionen zwischen Kindern und Studierenden, wobei rekonstruiert wird, wie beide Seiten die Relevanz kindlicher Erkl&auml;rungen herstellen und gespr&auml;chsstrukturelle Aufgaben gemeinsam bearbeiten. Die Ergebnisse zeigen, dass das Lehr-Lernarrangement Potenzial zur F&ouml;rderung von Erkl&auml;rkompetenz besitzt, insbesondere hinsichtlich der Dimensionen &bdquo;Kontextualisierung&ldquo; und &bdquo;Vertextung&ldquo;.</p>
<p>Im Lehr-Lernarrangement &bdquo;Wie Bilder laufen lernten&ldquo; erstellen Lehramtsstudierende gemeinsam mit mehrsprachig aufwachsenden Grundschulkindern einen Legom&auml;nnchen-Film. Beim dritten Projekttreffen lernen die Kinder den Begriff &bdquo;Storyboard&ldquo; kennen, entwickeln ein eigenes Storyboard f&uuml;r ihre Geschichte, bauen das Szenenbild auf und beginnen anschlie&szlig;end mit den Dreharbeiten.</p>
<p>Transkriptionskonventionen: GAT2 &ndash; Basistranskript<br />Ursprungsdatei: Audioaufnahme mit einem Audio-Recorder ZOOM H1n</p>
Simulationsmodell für die Auswirkungen verschiedener mietrechtlicher Umlagesysteme für Energie- und Modernisierungskosten auf Mieter und Vermieterinnen bei beispielhaften Gebäuden und Modernisierungsoptionen
No full textDas Simulationsmodell dient der Berechnung der Wirtschaftlichkeit je dreier Energieeffizienz-Modernisierungen bei fünf ausgewählten Beispielgebäuden unter der Annahme vierer mietrechtlicher Umlagesysteme für Energie- und Modernisierungskosten.
Das Modell entstand im Rahmen des FLAMME-Forschungsprojektes (Fairness, Lastenverteilung und Akzeptanz des Mietrechts bei Modernisierungen für Energieeffizienz), gefördert vom Bundesministerium für Wirtschaft und Klimaschutz, FKZ 03EI5231. Dem Forschungsverbund gehören an: Universität Kassel, Umweltbundesamt, ITG Dresden, FIW München.
Das Modell errechnet über einen Zeitraum von 20 Jahren (2023-2042) u.a. Energiekosten und Miethöhen und ermöglicht den Vergleich zwischen den Zahlungsströmen bei Erhalt des energetischen Status Quo und der Durchführung energetischer Modernisierungen.
Der Datensatz enthält fünf Excel-Spreadsheets mit Makros zur Berechnung der Zahlungen für die fünf Beispielgebäude. Weiterhin enthalten ist ein Excel-Spreadsheet ohne Makros zur Aggregation und Analyse der Ergebnisse der Sensitivitätsberechnung.03EI523
Monte-Carlo simulation of the three dimensional transfer function for coherence scanning interferometry [Code/Data]
No full textThe provided code is meant to simulate the 3D transfer function of a coherence scanning interferometer (CSI), which is a new approach to describe the transfer behavior of optical systems containing a depth scan. The software code is a python script which calculates the 3D optical transfer function by using a Monte-Carlo method applying reversed sampling. The related mathematical details and can be found in the related publication. The system which is simulated by the code is set to a numerical aperture of 0.9 and considers only monochromatic illumination of 440 nm. The .h5 dataset contains the raw data from the CSI measurement shown as a comparison. A silicon mirror was used as an measurement object, while the CSI used in this case is a Linnik setup. The provided code imports this dataset, plots an interferogram from one pixel and calculates its spectrum as a comparison to the histograms computed by the statistical Monte-Carlo simulation. The .npz files contain the analytically calculated transfer functions, based on the universal fourier optics model. The file "TF_ps.npz" is for the monochromatic case of royal blue illumination, while the file "TF_ps_spec_rb.npz" considers an full width of half maximum (FWHM) of 20 nm of the illuminating royal blue LED as presented in the paper. Running the simulation code should work without adjustments other than the paths of the datasets which have to be imported. Make sure plots of datasets that are not provided or necessary are commented out.LE 992/16-
An Initial Study of UHPC as Reusable Mold Material for Aluminum Casting
No full textDie Machbarkeit von Ultrahochleistungsbeton (UHPC) als Material fuer wiederverwendbare Formen im Aluminiumguss wird geprueft. Es wurden zwei spezielle UHPC-Formulierungen untersucht: eine auf der Basis von gewoehnlichem Portlandzement (OPC) und eine weitere unter Verwendung von alkalisch aktivierten Materialien (AAM), die aus mit Kaliwasserglas angeregtem Huettensandmehl bestanden. Der Schwerpunkt der Studie lag auf der Untersuchung der Oberflaeche durch Rauheitsmessungen und der thermischen Bestaendigkeit durch wiederholte Giesszyklen. Die thermische Stabilitaet der Formen wurde mittels thermogravimetrischer Analyse (TGA), Quecksilberdruckporosimetrie (MIP), Risssegmentierung, optischer Mikroskopie und Elektronenmikroskopie (REM) untersucht. Die Ergebnisse zeigen, dass aus AAM-UHPC hergestellte Formen gegenueber OPC-UHPC-Formen unter aehnlichen Bedingungen eine ueberlegene Stabilitaet bei Giesszyklen aufweisen. Es wurden mikrostrukturelle Veränderungen und die Wechselwirkung von UHPC-Materialien mit geschmolzenem Aluminium untersucht, wobei die geringe Adhaesion und Defektbildung deutlich wurde. Die damit hergestellten Gussbauteile wiesen eine solide Gussqualitaet auf, mit einer Korngroesse, die mit der von herkoemmlichen Stahlformen vergleichbar ist (~ 90 Mikrometer), was das Potenzial von UHPC-Werkstoffen zur Verbesserung der Gussqualitaet und -effizienz unterstreicht. Die Studie kommt zu dem Schluss, dass UHPC, insbesondere mit alkalisch aktivierten Formulierungen, vielversprechend fuer Niederdruckguss ist. Im Datensatz enthalten sind: - Abbildungen - Mikroskopdaten - Quecksilberdruck-Porosimetriemessungen - TGA-DSC Messungen 20 bis 800 Grad Celsius - XRD MessungenThe feasibility of ultra-high performance concrete (UHPC) as a material for reusable moulds in aluminium casting is being investigated. Two special UHPC formulations were investigated: one based on ordinary Portland cement (OPC) and another using alkali-activated materials (AAM) consisting of ground granulated blast furnace slag mixed with potassium silicate. The study focussed on the investigation of the surface by roughness measurements and the thermal stability by repeated casting cycles. The thermal stability of the moulds was investigated by thermogravimetric analysis (TGA), mercury intrusion porosimetry (MIP), crack segmentation, optical microscopy and electron microscopy (SEM). The results show that moulds made from AAM-UHPC exhibit superior stability to OPC-UHPC moulds under similar conditions during casting cycles. Microstructural changes and the interaction of UHPC materials with molten aluminium were investigated, revealing low adhesion and defect formation. The cast components produced exhibited solid casting quality, with a grain size comparable to that of conventional steel moulds (~90 microns), highlighting the potential of UHPC materials to improve casting quality and efficiency. The study concludes that UHPC, especially with alkali-activated formulations, is promising for low-pressure die casting. Included in the data set are: - Images - Microscope data - Mercury intrusion porosimetry measurements - TGA-DSC measurements 20 to 800 degrees Celsius - X-ray diffraction measurement