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Laser Micro-Wire Cladding: From Fundamental Mechanisms to Application
No full textLaser cladding using thin wires (<0.8 mm) presents significant potential for applications requiring high precision and minimal heat input, such as coatings for nuclear fuel rods. This work investigates Laser Micro-Wire Cladding (LMWC) using a 200 µm wire, showing the transition from fundamental process studies on single tracks and flat substrates to the application of FeCrAl coatings on 15-15Ti and 316L tubes relevant to nuclear fuel rods. High-resolution high-speed imaging (HSI) experiments revealed unique melt transfer characteristics, including a stable melt bridge and drop deposition mode. The mechanisms governing these modes were analysed. A novel wire-bending technique was developed to enhance process stability, crucial for consistent deposition. This understanding facilitated the successful deposition of thin (135 µm), low-dilution (< 7%), defect-free clad layers onto thin (500 µm) substrates. Characterization indicates that the coatings meet demanding requirements for nuclear applications.Fulltext license: CC BY</p
High‐Temperature Supercapacitors Enabled by Fluorine‐Free Ionic Liquid and Synergistic Alkali‐Doped Graphene Oxides
No full textThis study explores the synthesis and electrochemical performance of graphene oxide co-doped with sodium and potassium (Na–K–GO) as electrode materials for supercapacitors (SCs) designed to operate at 60°C over an extended voltage window. The Na–K–GO is employed as the electrode material, while a fluorine-free ionic liquid (IL), [P4444][MEEA]—comprising a tetrabutylphosphonium cation and a 2-2-(2-methoxyethoxy)ethoxy anion—served as the electrolyte, enabling stable operation over a wide voltage window at elevated temperatures. Using this combination, three coin-cell SCs are fabricated: two symmetric devices (SC-1 and SC-2) and one asymmetric device (SC-3). All the three exhibited remarkable charge storage abilities, a retaining performance over 10 000 charge–discharge cycles at 60°C. Among the three devices, SC-3 exhibited the best overall electrochemical performance, delivering a high specific capacitance of 47.01 F g−1 and an energy density of 27.77 Wh kg−1 at 0.5 A g−1. Even at a higher current density of 1 A g−1, SC-3 maintained a maximum power density of 1000 W kg−1 while sustaining an energy density of 14.21 Wh kg−1, reflecting its strong rate capability. Moreover, the long-term cycling tests at 2 A g−1 demonstrated an outstanding durability of SC-3, which retained 99% coulombic efficiency after 10 000 cycles, significantly outperforming the SC-2 (90%) and SC-1 (79%).Fulltext license: CC BY</p
Diversitet av ryggradslösa djur (evertebrater) i dagvattenpåverkade urbana vattendrag via eDNA
No full textDenna studie undersökte ekologiska effekter av urbanisering och urban dagvattenavrinning på vattendrag som passerar genom urbana områden. Diversitet av makroevertebrater (ryggradslösa djur) analyserades med environmental DNA (eDNA) metabarkodning av biofilmprover. Dessa har samlats in vid flera platser längs tre vattendrag i södra Sverige. Proverna samlades in längs en gradient från landsbygd uppströms till urbanpåverkade områden nedströms. Generellt dominerades makroevertebratsamhällena av föroreningståliga taxa, särskilt Chironomidae (fjädermyggor), vilket indikerar antropogent tryck längs provsträckan från uppströms till nedströms. Även om diversiteten ökade nedströms speglade detta en ökad heterogenitet av habitat som gynnar föroreningståliga arter snarare än ekologiska förbättringar, vilket speglar en möjlig påverkan från urbana områden och därmed från dagvatten.Dag&Nä
Classifying climate-related failures for regional-national railway networks
No full textThe frequency and intensity of extreme weather events pose various types of hazards and vulnerabilities to the railway system. This article aims to challenge the assumption that a single, nationally and internationally aggregated model is sufficient to capture region-specific failure patterns. While useful, these national models are often unable to account for linkages and feedback between heterogeneous regions and associated railway failure mechanisms and processes. This study develops and evaluates regional-national specific machine learning (ML) framework to enhance the classification of climate-related railway failures utilizing a synchronized five-fold cross-validation strategy. We illustrate the approach through a case study of the Switches and Crossings (S&C) assets across five railway operational regions in Sweden, over a 24-year period, to demonstrate meaningful climate variability. Our methodology provides a consistent procedure that consistently compares national models with region-specific models. Results show that the localized model outperforms the national baseline, with improvements of up to 2.0% in Matthews Correlation Coefficient and 1.2% in F1-score at the 24-hour window preceding failure. Shapley Additive Explanations (SHAP) analysis revealed regionally distinct predictors, such as snow accumulation in the North and weather data coverage issues in the West. The results provide a basis for further process refinement, offering interpretable insights for operation and maintenance planning, risk assessment and supporting climate adaptation actions to achieve a climate-proof and resilient railway system. Godkänd;2025;Nivå 0;2025-12-22 (u8);Full text license: CC BYClimate Adaptation and Risk Mitigation of Swedish Railway Infrastructure (AdaptRail
Observation of Coherent (1020) Meson Photoproduction in Ultraperipheral PbPb Collisions at √NN=5.36 TeV
No full textThe first observation of coherent (1020) meson photoproduction off heavy nuclei is presented using ultraperipheral lead-lead collisions at a center-of-mass energy per nucleon pair of 5.36 TeV. The data were collected by the CMS experiment and correspond to an integrated luminosity of 1.62 μ−1. The (1020) meson signals are reconstructed via the +− decay channel. The production cross section is presented as a function of the (1020) meson rapidity in the range 0.3<||<1.0, probing gluons that carry a fraction of the nucleon momentum () around 10−4. The observed cross section exhibits little dependence on rapidity and is significantly suppressed, by a factor of ∼5, compared to a baseline model that treats a nucleus as a collection of free nucleons. Theoretical models that incorporate the nuclear shadowing effect generally provide a better description of the (1020) data than those incorporating gluon saturation. This study establishes a powerful new tool for exploring nuclear effects and nuclear gluonic structure in the small- regime at a unique energy scale bridging the perturbative and nonperturbative quantum chromodynamics domains.Full text license: CC BY 4.0;For funding information, see: https://journals.aps.org/prl/abstract/10.1103/2ssw-wwyy</p
Elucidating the Behaviour of Hybrid Fibre-Reinforced Concrete Using Post-Consumer Carpet Fibres
No full textCarpet waste degrades slowly, posing an environmental burden. Incorporating this waste as fibre reinforcement in concrete helps to reduce accumulation and improve the properties of concrete. However, varying fibre characteristics and their interaction in blends are not well established. Hence, understanding hybrid fibre effects is crucial for construction adoption. This study evaluates the mechanical performance, shrinkage, microstructure, pore structure, and interfacial characteristics of hybrid carpet fibre-reinforced concrete. Four fibres, nylon, polypropylene (PP), polytrimethylene terephthalate (PTT), and polyester were analysed using grey relation analysis in six hybrid combinations with three mix ratios at a 0.3% volume fraction. At 28 days, flexural and splitting tensile strengths increased by 4–11% and 8–26%, respectively. All mixtures exhibited reduced shrinkage compared to the control. The nylon/PP 2:1 mix showed the best overall performance. Microstructural analysis revealed pore refinement, reduced porosity, and improved fibre–matrix bonding influenced by fibre hydrophilicity or hydrophobicity. Nanoindentation indicated hydrophilic fibres minimized the interfacial transition zone thickness. The findings indicate fibre combinations exhibit additive effects. This suggests performance can be predicted for blended fibre mixes, potentially allowing the design of mixes using fibre combinations to compensate for poorer performing fibres, enabling their reuse and avoiding landfill disposal.Full text license: CC BY-NC-ND 4.0;Funder: Australian Research Council project (DE230101221)</p
XXXVI Konferencja z Historii Matematyki, Będlewo 2025 : [XXXVI Conference on the History of Mathematics, Będlewo 2025]
No full textPoniższy tekst zawiera informacje o XXXVI Konferencjiz Historii Matematyki, która odbyła się w Będlewie w dniach 18–22maja 2025 roku.This text contains information about XXXVI Conference on the History of Mathematics, which took place in The Mathematical Research and Conference Center of the Institute of Mathematics of the Polish Academy of Sciences in Będlewo on 18–22 May 2025.Full text license: CC BY 3.0</p
The Sisters B.: Collaborative Film Practice Using Embodied Montage Strategie
No full textThis article is an invitation into an artistic research project on team-based filmmaking. Its format takes a montage approach congenial with the research ambitions: writings on a film process are interspersed by texts on research methods, script scenes, historical images and facts, while loosely traced by comic strips in the intended film’s chronology. The Sisters B. project responds to a lack of research on and through collaborative film practice. We situate the project in our time’s flood of media-based storytelling and ecological crises. This project’s multifaceted and exploratory approaches are informed by the complexity and entanglement of consequences – to environment, people and otherwise, directly and ideologically – of both cinematic production and its narratives. Our methodological framework draws from several academic fields and artistic disciplines, manifested through the article’s exposition of a filming week on the Bergman Estate. The Sisters B. explores loss and conditions for creativity through an embodied conversation with the composers Lili (1893-1918) and Nadia (1887-1979) Boulanger. The article proposes a range of embodied montage strategies; intertwining narrative levels, connecting times, activating audience imagination, embracing friction, responding to circumstances, producing by re-using; porously overlapping fact and fiction, theory and practice by relating biography, ecology and rhythmic gestures to script, performance and film editing.Full text license: CC BY-NC</p
Assessing the Accuracy of NASA Power Meteorological Data in Iraq : [تقييم دقة بيانات األرصاد الجوية لوكالة ناسا في العراق]
No full textThis study assesses the precision of NASA Power meteorological data in Iraq over a 12-year period, utilizing data from 10 meteorological stations. The research focuses on key meteorological parameters, i.e., average daily temperatures, rainfall, wind speed, solar radiation, and relative humidity. Through transparent data analysis and comparison, the validity of NASA Power in local climate monitoring within Iraq is evaluated. Through statistical analysis, the correlation between NASA Power data and meteorological station data is evaluated using Kendall's Tau correlation coefficient test and Mean Bias Error (MBE). The comparison of NASA Power meteorological data with observed data from ten meteorological stations in Iraq revealed significant findings. NASA Power data displayed a high correlation (0.748-0.912) with observed temperatures, indicating accuracy in temperature assessment. The data also showed weak to strong correlations (0.105-0.526) for rainfall and weak to moderate correlations (0.105-0.427) for wind speed, suggesting potential supplementary use, albeit with the need for calibration. For solar radiation, NASA Power data exhibited a strong to very strong correlation (r = 0.636-0.834), making it suitable for solar assessments. For relative humidity, a very strong correlation (r = 0.636-0.834) was demonstrated, indicating the need for further analysis. Despite its reliability as a meteorological data source in Iraq, NASA Power data should undergo validation across various applications and regions to ensure its accuracy and dependability.تقيم هذه الدراسة دقة بيانات األرصاد الجوية Power NASA في العراق على مدى 12 عا ًما، باستخدام بيانات من 10 محطات أرصاد جوية. يركز البحث على المعلمات الجوية الرئيسية: متوسط درجات الحرارة اليومية، وهطول األمطار، وسرعة الرياح، واإلشعاع الشمسي، والرطوبة النسبية. من خالل تحليل البيانات ومقارنتها بشكل شفاف، يتم تقييم صحة Power NASAفي مراقبة المناخ المحلي داخل العراق. من خالل التحليل اإلحصائي، يتم تقييم االرتباط بين بيانات Power NASAوبيانات محطة األرصاد الجوية باستخدام اختبار معامل ارتباط كيندال تاو وخطأ التحيز المتوسط .(MBE (أظهرت مقارنة بيانات األرصاد الجوية لـ Power NASA مع البيانات المرصودة من عشر محطات أرصاد ًطا عاليًا )0.748 - 0.912( مع درجات الحرارة المرصودة، مما يشير جوية في العراق نتائج مهمة: أظهرت بيانات Power NASA ارتبا( لهطول األمطار وارتبا 0.105 ًط إلى الدقة في تقييم درجة الحرارة، بينما أظهرت ارتبا 0.105 - 0.526 ا ضعيفًا إلى متوسط ) ًطا ضعيفًا إلى قوي )- 0.427( لسرعة الرياح، مما يشير إلى االستخدام التكميلي المحتمل مع الحاجة إلى المعايرة. بالنسبة لإلشعاع الشمسي، أظهرت بيانات NASAارتبا 0.636 - 0.834(، مما يجعلها مناسبة لتقييمات الطا قة الشمسية، وبالنسبة للرطوبة النسبية، فقد أظهرت ًط Power ا قويًا إلى قوي ج ًدا )ارتبا 0.636 - 0.834( لمزيد من التحليالت. وعلى الرغم من موثوقيتها كمصدر للبيانات الجوية في العراق، يجب أن تخضع بيانات ًطا قويًا ج ًدا ) Power NASA للتحقق عبر تطبيقات ومناطق مختلفة لضمان دقتها وموثوقيتها.Godkänd;2025;Nivå 0;2025-12-31 (u8);Full text license: CC BY</p
Search for New Physics in Jet Multiplicity Patterns of Multilepton Events at √ =13 TeV
No full textA first search for beyond the standard model physics in jet multiplicity patterns of multilepton events is presented, using a data sample corresponding to an integrated luminosity of 138 fb−1 of 13 TeV proton-proton collisions recorded by the CMS detector at the LHC. The search uses observed jet multiplicity distributions in one-, two-, and four-lepton events to explore possible enhancements in jet production rate in three-lepton events with and without bottom quarks. The data are found to be consistent with the standard model expectation. The results are interpreted in terms of supersymmetric production of electroweak chargino-neutralino superpartners with cascade decays terminating in prompt hadronic -parity violating interactions.Full text license: CC BY 4.0;For funding information, see: https://journals.aps.org/prl/abstract/10.1103/51fw-klz3</p