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Exploring electrical resistivity tomography (ERT) to detect soil pipes : theoretical modeling and field experiments
No full textSoil erosion research remains critical for sustainable development as it impacts soil health through different erosive processes. Recent studies on soil piping highlight advancements in detecting surface features (using UAV); however, detecting underground pipes still remains challenging. This study aims to evaluate electrical resistivity tomography (ERT), a frequently used geophysical method, for detecting soil pipes. The study was based on field experiments conducted in the Bieszczady Mountains (the Carpathians, SE Poland) and theoretical modeling using Resistivity 2D modeling software. The results were compared with the existing research and confirmed by the trench. We evaluated various measurement settings, including array configurations (Wenner—W, Wenner-Schlumberger—WS and dipole–dipole—DD), electrode spacing, and measurement orientation through the pipe system to determine their impact on detecting pipes regarding their size, shape, and depth. We performed six ERT profiles in the field, and we modeled the electrical response of a theoretical void at varying subsurface positions. In the theoretical modeling, we considered two scenarios with root-mean-squared errors (RMS) of 0% and 5%. The results confirmed that higher resistivity anomalies indicated pipes, with the DD configuration showing lower resistivity (105 Ωm) compared to W and WS configurations (268–427 Ωm). The comparison with other studies indicates that there is no universal threshold confirming soil pipe presence; instead, a clear electrical contrast with surroundings is crucial. Our findings suggest that while all tested configurations effectively detect pipes, their choice impacts image quality in the case of anomaly contrast and shape dependent on the sensitivity of the selected configuration. We recommend using the WS configuration for detecting both vertical and horizontal features. The number of anomalies influences RMS and should be critically evaluated during surveys. Our findings can assist researchers and practitioners in designing ERT studies in different environments
Focus group interview in educational research
No full textMetoda zogniskowanych wywiadów grupowych stanowi instrument badawczy umożliwiający gromadzenie danych jakościowych, poprzez analizę opinii, poglądów i spostrzeżeń uczestników w sytuacji interakcyjnej, wspieranej odpowiednią infrastrukturą. W artykule przedstawiono potencjał zastosowania grup fokusowych w badaniach z zakresu andragogiki, wskazując na ich rosnącą popularność. Tekst przedstawia metodę wywiadów fokusowych uwzględniając różne warianty oraz metodykę zastosowania. Autorzy analizują zarówno potencjał wykorzystania tej metody i jej ograniczenia, szczególnie w badaniach jakościowych skoncentrowanych na procesie uczenia się w dorosłości.The focus group interview method provides a research instrument for collecting qualitative data by analysing the opinions, views and perceptions of participants in an interactive situation supported by an appropriate infrastructure. The article outlines the potential of using focus groups in andragogy research, pointing to their growing popularity. The text presents the focus interview method taking into account the different variants and the methodology of application. The authors analyse both the potential for the use of this method and its limitations, especially in qualitative research focusing on learning in adulthood
Realization of complex‐shaped magnetic nanotubes with 3D printing and electrodeposition
No full textThe expansion of nanomagnetism to the third dimension leads to phenomena such as curvature-induced magnetochirality and anisotropy, which can significantly influence the behavior of magnetic textures. One of the most promising systems is the magnetic nanotube – where intrinsic curvature effects are present. However, studies of magnetic nanotubes remain limited to straight systems, and little is known about the influence of 3D geometries. In this work, three dimensional (3D) complex-shaped nanotubes are fabricated by combining nanoprinting with the conformal deposition of magnetic films. Specifically, 3D conductive non-magnetic tungsten scaffolds are fabricated using focused electron beam induced deposition and subsequently coated with a nickel magnetic shell, resulting in complex-shaped magnetic nanotubes whose geometry can be controlled by tuning the electron-beam parameters and electrodeposition conditions. Performing X-ray microscopy revealed that nanotubes of various geometries host a vortex-like azimuthal state, and that the energy landscape of the magnetic configuration can be tailored geometrically. Specifically, the pinning of magnetic domain walls at curved vertices is observed experimentally and confirmed with micromagnetic simulations, offering geometrical control of magnetic configurations in nanotube architectures. This approach provides a new pathway to fabricate and study complex 3D core-shell magnetic structures, facilitating experimental investigations of their fundamental properties, key for the next-generation of spintronic devices
Reporting guidelines can be used to foster reporting of evidence-based research principles : a cross-sectional study
No full textPediatric MASLD in severe obesity : current clinical perspectives on diagnosis and treatment
No full textStructural changes of iron active sites in zeolite FER during and conversion to oxygenates
No full textThe direct co-conversion of and into oxygenates offers an atom-efficient strategy for the simultaneous valorization of two major greenhouse gases. This work presents an integrated spectroscopic, diffraction, and computational investigation of Fe-containing ferrierite (Fe-FER) as a bifunctional catalyst capable of selectively transforming and into methanol and acetic acid, with methanol further converted into olefins. In situ FTIR–MS studies reveal sequential formation of methanol and acetic acid, indicating that under mild conditions, is first oxidized to methanol on redox-active Fe centers, followed by methanol carbonylation on Brønsted acid sites. At elevated temperatures, methanol-to-olefin conversion becomes competitive. Mössbauer spectroscopy shows that the interaction of Fe(II) with decreases the electron density around Fe nuclei, resulting in partial oxidation and coordination changes between tetrahedral and octahedral environments. Neutron powder diffraction confirms Fe displacement within the 6-membered ring plane upon interaction, while subsequent exposure restores Fe(II) species in tetrahedral coordination. Density functional theory, combined with machine-learning interatomic potentials, identifies hydrocarbonate species as key intermediates inducing Fe oxidation and local structural distortion, consistent with experimental observations. The cooperative interplay of redox-active and acidic sites enables coupled activation of and oxidation of with complete atom utilization. Overall, two types of Fe(II) species with distorted tetrahedral symmetry are involved in activation, whereas other Fe(II) species remain inactive, establishing Fe-FER as a structurally flexible and electronically adaptive catalyst for sustainable conversion chemistry
Exploring maximum likelihood and Bayesian approaches for two-dimensional image restoration : a machine learning perspective
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