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56 spider species have been recorded in a 4-hours-fieldtrip. Twelve of them are endangered according to the red data book for spiders in Germany. Some interesting species are mentioned with comments on their habitat preference and distribution limits. Figures of two species (Theridion nigrovariegatum, Dipoena erythropus) are given because of variation in their genitalia.

Although strong references to expertise in different theoretical approaches to teacher noticing have been made in the last decades, empirical knowledge about the development of teacher noticing from novice to expert level is scarce. The present study aims to close this research gap by comparing three different groups of mathematics teachers with different degrees of professional teaching experience--pre-service teachers at the master's level, early career teachers, and experienced teachers--using data sampled in the frame of the research program from the Teacher Education and Development Study in Mathematics (TEDS-M). Furthermore, the construct of teacher noticing is assessed in a differentiated way by analyzing different noticing facets. Findings confirm that three facets of teacher noticing can be empirically distinguished--perception of important classroom events, their interpretation, and decisions regarding further developments. The results reveal a considerable increase in professional noticing between master's students and practicing teachers. However, in contrast to other studies, among examples from East Asia, a stagnation or decrease in professional noticing between early career teachers and experienced teachers could be observed. Overall, the study highlights the cultural dependency of expertise development regarding teachers' noticing.

Although mathematical modeling plays an important role in many curricula worldwide, significant discrepancies persist in the importance of mathematical modeling in ordinary mathematics classrooms and teacher education. This paper compares pre-service mathematics teachers' professional mathematical modeling competencies in three different regions--Germany, Mainland China, and Hong Kong--where educational and cultural traditions differ, including the role of mathematical modeling. In total, 232 pre-service mathematics teachers from the three regions completed a modeling task covering mathematics content knowledge (MCK) of modeling and mathematical pedagogical content knowledge (MPCK) of modeling. The results show that pre-service teachers from Germany demonstrated the strongest MCK and MPCK of mathematical modeling; by contrast, pre-service mathematics teachers from Mainland China and Hong Kong demonstrated relatively weaker MCK and MPCK of mathematical modeling. MCK and MPCK of mathematical modeling were also found to be unevenly developed at different competence levels for the three regions. These differences may be attributed to the history of mathematical modeling in mathematics curricula, teacher education, and teaching culture in these three regions.

Understanding how reaction heterogeneity impacts cathode materials during Li‐ion battery (LIB) electrochemical cycling is pivotal for unraveling their electrochemical performance. Yet, experimentally verifying these reactions has proven to be a challenge. To address this, we employed scanning μ‐XRD computed tomography to scrutinize Ni‐rich layered LiNi0.6Co0.2Mn0.2O2 (NCM622) and Li‐rich layered Li[Li0.2Ni0.2Mn0.6]O2 (LLNMO). By harnessing machine learning (ML) techniques, we scrutinized an extensive dataset of μ‐XRD patterns, about 100,000 patterns per slice, to unveil the spatial distribution of crystalline structure and microstrain. Our experimental findings unequivocally reveal the distinct behavior of these materials. NCM622 exhibits structural degradation and lattice strain intricately linked to the size of secondary particles. Smaller particles and the surface of larger particles in contact with the carbon/binder matrix experience intensified structural fatigue after long‐term cycling. Conversely, both the surface and bulk of LLNMO particles endure severe strain‐induced structural degradation during high‐voltage cycling, resulting in significant voltage decay and capacity fade. This work holds the potential to fine‐tune the microstructure of advanced layered materials and manipulate composite electrode construction in order to enhance the performance of LIBs and beyond. [ABSTRACT FROM AUTHOR]

Direct current (DC) magnetometry data obtained for polycrystalline Mg3V4(PO4)6 were fitted by various magnetic models based on angular momentum basis states. As a result, single‐ion anisotropy of the magnetic V 3+ ions could be identified to decisively determine the magnetic properties of Mg3V4(PO4)6 and not antiferromagnetic exchange interaction between V ions as supposed in literature. It could be demonstrated analytically, by utilization of the Van Vleck equation, that also single‐ion anisotropy can lead to a linear and origin shifted inverse susceptibility curve in the high temperature region. The Weiss constant obtained from a Curie‐Weiss fit to such a susceptibility curve might falsely be ascribed to antiferromagnetic exchange interactions if additional low temperature magnetic properties are not considered for verification. [ABSTRACT FROM AUTHOR]

Direct current (DC) magnetometry data obtained for polycrystalline Mg3V4(PO4)6 were fitted by various magnetic models based on angular momentum basis states. As a result, single‐ion anisotropy of the magnetic V 3+ ions could be identified to decisively determine the magnetic properties of Mg3V4(PO4)6 and not antiferromagnetic exchange interaction between V ions as supposed in literature. It could be demonstrated analytically, by utilization of the Van Vleck equation, that also single‐ion anisotropy can lead to a linear and origin shifted inverse susceptibility curve in the high temperature region. The Weiss constant obtained from a Curie‐Weiss fit to such a susceptibility curve might falsely be ascribed to antiferromagnetic exchange interactions if additional low temperature magnetic properties are not considered for verification. [ABSTRACT FROM AUTHOR]

Herein, the synthesis of Co2Si5N8 nitridosilicate from α‐Ca2Si5N8 by ion exchange is described. The monoclinic Co2Si5N8$\left(\text{Co}\right)_{2} \left(\text{Si}\right)_{5} \left(\text{N}\right)_{8}$ structure (space group Cc) is compared with those of the related nitridosilicates Ca2Si5N8 and Fe2Si5N8 its magnetic properties are profoundly investigated. Most interestingly, polycrystalline Co2Si5N8 exhibits a quasi‐temperature‐independent paramagnetic susceptibility of about 6×10−3 cm3 mol−1$>$$ 6\times {10}^{-3} {\text{cm}}^{3} {\text{mol}}^{-1}$$ over a wide temperature range from 100 to 600 K. Two different magnetic models based on a phenomenological Hamiltonian that takes into account magnetic exchange coupling, crystal‐field interactions, and Zeeman effects within the framework of an angular momentum basis set are refined to the experimental susceptibility datasets. The results of the refinements point to the realization of a pseudo temperature independent paramagnetism for Co2Si5N8 that results from a near‐perfect cancellation of temperature‐dependent contributions to the susceptibility depending delicately on the mixing of ion levels in the electronic states, their relative energies, and the magnetic coupling between them. Additionally, performed direct current field scan, alternating current susceptibility, and heat capacity measurements complete the magnetic characterization and facilitate the identification of impurity phase contributions. [ABSTRACT FROM AUTHOR]

The present work describes the dynamic magnetic properties of the complex [(CpAr3)4Dy III2 Cl4K2]·3.5(C7H8) (1), synthesized by employing a tri-aryl-substituted cyclopentadienyl ligand (CpAr3), [4,4′-(4-phenylcyclopenta-1,3-diene-1,2-diyl)bis(methylbenzene) = CpAr3H]. Each Dy(III)-metallocene weakly couples via K2Cl4, displaying slow relaxation of magnetization below 14.5 K under zero applied dc field via KD3 energy levels with an energy barrier of 136.9/133.7 cm−1 on the Dy sites. The single-ion axial anisotropy energy barrier is reduced by geometrical distortion due to the coordination of two chloride ions at each Dy centre. [ABSTRACT FROM AUTHOR]

Rating scales are a popular item format used in many types of assessments. Yet, defining which rating is correct often represents a challenge. Using expert ratings as benchmarks is one approach to ensuring the quality of a rating instrument. In this paper, such expert ratings are analyzed in detail taking a video-based test instrument of teachers' professional competencies from a follow-up study to TEDS-M (the so-called TEDS-FU study) as an example. The paper focuses on those items that did NOT reach sufficient consensus among the experts and analyzes in depth their features by coding the experts' comments on those items and additionally considering their rating outcome. The results revealed that the item-wording and the composition of the group of experts strengthened or weakened agreement among the experts.

As contemporary battery applications such as electric vehicles demand higher energy densities, layered LiNiO2 (LNO) could contribute as the end-member of the LiNi1−x−yCoxMnyO2 (NCM) family with the highest extractable specific capacity in a practical voltage window. Achieving high capacities requires among other things a defect free crystal structure, which is not easily achieved due to the natural occurrence of Ni excess on the Li site (NiLi) and/or antisite defects where Ni and Li switch crystallographic sites. Here, we present a study of the evolution of point defects in a series of LNO samples varying from underlithiated to fully lithiated stoichiometry in layered Li1−zNi1+zO2 with −0.05 ≤ z ≤ 0.35. Using the high angular resolution of synchrotron X-ray diffraction complemented with the different elements contrast provided by neutron diffraction, we are able to identify two defect regimes. In the first regime, at the underlithiated end, both NiLi as well as Li on the Ni site (LiNi) defects are present. Inhibited crystal growth during synthesis is found to coincide with the presence of these LiNi defects for z ≥ 0.15. Upon decreasing z values and the vanishing of LiNi, the primary particle size distribution as well as average refined crystallite size increases. Investigation of the local structure by nuclear magnetic resonance reveals the presence of a Li environment not detected by diffraction methods at low z, the Li-rich end of the sample series. Finally, magnetometry data suggest the onset of the ferrimagnetic-to-antiferromagnetic transition in LNO correlates with the elimination of LiNi defects in the structure. The present study thus not only highlights the correlation between defect chemistry and physical properties, but also shows the relationship to crystal growth, a field highly relevant for industrial battery cathode materials engineering. [ABSTRACT FROM AUTHOR]