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  • Efficacy of modal curvature damage detection in various pre-damage data assumptions and modal identification techniques
    • Milena Drozdowska
    • Marek Szafrański
    • Anna Szafrańska
    • Agnieszka Tomaszewska
    2025 Pełny tekst Bulletin of the Polish Academy of Sciences-Technical Sciences

    The efficacy of modal curvature approach for damage localization is discussed in the paper in the context of input data. Three modal identification methods, i.e., Eigensystem Realization Algorithm (ERA), Natural Excitation Technique with ERA (NExT-ERA) and Covariance Driven Stochastic Subspace Identification (SSI-Cov), and four methods of determining baseline data, i.e., real measurement of the undamaged state, analytical function, Finite Element (FE) model and approximation of current experimental mode shape, are considered. Practical conclusions are formulated based on analysis of two cases. The first is a laboratory beam with a notch and the second is a stone masonry historic lighthouse with modern restoration in its upper part. The analysis shows that NExT-ERA and SSI-Cov in combination with approximation of current mode shape provide high efficacy in damage localization alongside relatively straightforward determination of baseline data. It proves that the construction of advanced FE models of a structure can be replaced with a much simpler method of baseline data acquisition. Furthermore, the research shows the structural mode shapes identified with ERA may not always indicate the presence of damage.

  • Ekspertyz techniczne zabytkowych obiektów budowlanych . Wybrane zagadnienia
    • Maciej Niedostatkiewicz
    2025

    Współczesna tendencja do skracania czasu realizacji prac remontowo- naprawczych obiektów budowlanych będących zabytkami nieruchomymi, przy jednoczesnym ograniczaniu zakresu oraz stopnia szczegółowości dokumentacji projektowej, jak również często realizowane zmiany sposo- bu użytkowania obiektów zabytkowych wymagają zwrócenia szczególnej uwagi na zagadnienie właściwej oceny stanu technicznego tego typu obiek- tów prowadzonej na etapie przygotowywania opracowań o charakterze eksperckim, określanych powszechnie jako ekspertyzy techniczne. W książce omówiono najważniejsze elementy i zagadnienia na które należy zwrócić uwagę podczas realizacji opracowań eksperckich dotyczących zabytków nieruchomych

  • Electrifying the bus network with trolleybus: Analyzing the in motion charging technology
    • Mikołaj Bartłomiejczyk
    • Priscilla Caliandro
    2025 APPLIED ENERGY

    Currently, electric buses are becoming more and more popular, and their number in operation is increasing. The range of electric buses is also increasing and solutions that seem to be working almost without fixed infrastructure are being promised. However, this requires the use of high-capacity batteries, which increases the weight and price of the vehicle and causes high costs of battery replacement during operation. Moreover, if we take into account the growing demand for batteries, limited raw material resources, and the environmental impact of the battery production process, the optimization of battery capacity in vehicles may turn out to be a key issue. In this light, trolleybus becomes a sustainable and economically efficient bus electrification technology, if considered in an international scope and a medium- to long-term approach. The article provides a comprehensive study of challenges and potential solutions related to electric buses, which covers the theoretical analysis, technical aspects and practical applications, thus making a valuable resource for readers interested in sustainable urban transport systems. It presents the trolleybus technology, especially with modern solutions, as a sustainable and economically efficient tool for bus electrification. The article shows that the In Motion Charging (IMC) system reduces the need for high-capacity batteries under 100 kWh, which allows to extend their service life up to 15 years and, consequently, to reduce the number of buses needed for operation. The research was based on real measurement data from the transport system in Gdynia (Poland).

  • Electrospun Fibers from Biobased and Recycled Materials for Indoor Air Quality Enhancement
    • Natalia Czerwinska
    • Chiara Giosuè
    • Nicola Generosi
    • Mattia Pierpaoli
    • Rida Jbr
    • Francesca Luzi
    • Valeria Corinaldesi
    • Maria Letizia Ruello
    2025 MOLECULES

    Air filters are crucial components of building ventilation systems. Compared to conventional air filter media like glass fibers and melt-blown fibers, electrospinning membranes are more efficient for capturing various pollutants due to the smaller pores present on the structure. In this paper, activated carbon filters were prepared with eco-friendly polylactic acid (PLA) and microcrystalline cellulose (MCC) using electrospinning to obtain a high-quality factor (QF) fibrous mat for aerosol particle matter (PM) filtration and volatile organic compounds (VOCs) adsorption. Several configurations of the final membranes were investigated and tested for fiber morphology and air filtration performance. Filtering efficiency and adsorption properties were evaluated in a real-scale room by measuring the particle penetration of the newly synthesized and commercial filters against neutralized aerosol particles (3% NaCl aqueous solution) and VOCs (methyl ethyl ketone). The calculated depolluting efficiencies were up to 98% in terms of PM and 55% for VOCs abatement, respectively. Our results indicate that the proposed hybrid membranes represent promising materials for highly efficient and sustainable air filters for home application systems.

  • Elicited Production of Essential Oil with Immunomodulatory Activity in Salvia apiana Microshoot Culture
    • Agata Król
    • Adam Kokotkiewicz
    • Bożena Zabiegała
    • Klaudia Ciesielska-Figlon
    • Ewa Bryl
    • Maciej Jacek Witkowski
    • Adam Buciński
    • Maria Łuczkiewicz
    2025 MOLECULES

    Salvia apiana Jepson is an endemic North American species characterized by a rich phytochemical profile including abietane-type diterpenoids, phenolic acids, flavonoids, and thujone-free essential oil (EO). The current study was aimed at increasing EO production in bioreactor-grown S. apiana microshoot culture through biotic elicitation using chitosan, ergosterol, and yeast extract (YE). Additionally, the immunomodulatory effects of the major volatile constituent of white sage—1,8-cineole—as well as EOs obtained from both S. apiana microshoots and leaves of field-grown plants, were assessed. EOs were isolated via hydrodistillation and analyzed by GC/MS and GC/FID. Biological assays included flow cytometric evaluation of the proliferation and apoptosis rates of human CD4 and CD8 T lymphocytes, obtained from healthy volunteers and subjected to different concentrations of EOs and 1,8-cineole. Elicitation with 100 mg/L YE improved the production of EO in S. apiana microshoots by 9.4% (1.20% v/m). EOs from both microshoots and leaves of field-grown plants, as well as 1,8-cineole, demonstrated dose-dependent anti-proliferative and pro-apoptotic effects on CD4+ and CD8+ T cells. These findings highlight the potential of S. apiana microshoot cultures capable of producing EO with significant immunomodulatory activity

  • Elucidating charge transfer process and enhancing electrochemical performance of laser-induced graphene via surface engineering with sustainable hydrogel membranes: An electrochemist's perspective
    • Mohsen Khodadadiyazdi
    • Aiswarya Manohar
    • Adrian Olejnik
    • Agata Smułka
    • Agnieszka Kramek
    • Mattia Pierpaoli
    • Mohammed Saeb
    • Robert Bogdanowicz
    • Jacek Ryl
    2025 TALANTA.The International Journal of Pure and Applied Analytical Chemistry

    Laser-induced graphene (LIG) has emerged as a promising solvent-free strategy for producing highly porous, 3D graphene structures, particularly for electrochemical applications. However, the unique character of LIG and hydrogel membrane (HM) coated LIG requires accounting for the specific conditions of its charge transfer process. This study investigates electron transfer kinetics and the electroactive surface area of LIG electrodes, finding efficient kinetics for the [Fe(CN)6]3-/4- redox process, with a high rate constant of 4.89 x 10−3 cm/s. The impact of polysaccharide HM coatings (cationic chitosan, neutral agarose and anionic sodium alginate) on LIG's charge transfer behavior is elucidated, considering factors like ohmic drop across porous LIG and Coulombic interactions/permeability affecting diffusion coefficient (D), estimated from amperometry.It was found that D of redox species is lower for HM-coated LIGs, and is the lowest for chitosan HM. Chitosan coating results in increased capacitive share in the total current while does not apparently reduce Faradaic current. Experimental findings are supported by ab-initio calculations showing an electrostatic potential map's negative charge distribution upon chitosan chain protonation, having an effect in over a two-fold redox current increase upon switching the pH from 7.48 to 1.73. This feature is absent for other studied HMs. It was also revealed that the chitosan's band gap was reduced to 3.07 eV upon acetylation, due to the introduction of a new LUMO state. This study summarizes the operating conditions enhanced by HM presence, impacting redox process kinetics and presenting unique challenges for prospective LIG/HM systems' electrochemical applications.

  • Energy landscape and structural transformations of C38 penta-fullerene: The stabilizing role of octagons and insights into penta-octa-penta-fullerene
    • Kinga Warda
    • Szymon Winczewski
    • Julien Guthmuller
    2025 Materials Today Communications

    Theoretical investigations were conducted to study the stability and energy landscape of C38 penta-fullerene, a structure comprising six penta-graphene unit cells. Vibrational analysis at the B3LYP/def2SVP level revealed 18 negative frequencies, indicating the dynamic instability of penta-fullerene. Analyzing the energy profiles for these vibrational modes led to the identification of six energetically favourable isomers, featuring octagons and pentagons. Additionally, ab initio molecular dynamics (AIMD) at 300 K revealed a structure (named popfullerene) resembling the 0-dimensional equivalent of penta-octa-penta-graphene. Subsequent analyses confirmed the dynamic stability of pop-fullerene and op-fullerene, another identified isomer. According to binding energy (Eb) calculations, both isomers exhibit greater stability than penta-fullerene. Moreover, popfullerene, having Eb = -8.52 eV, demonstrates higher thermodynamic stability than C20 but lower stability than C60. AIMD simulations confirmed the thermal stability of pop-fullerene, even at 2000 K. B3LYP/def2QZVP calculations revealed bond lengths in pop-fullerene ranging from 1.37 to 1.51 Å, with one unique triple bond of 1.23 Å. The valence angles span from 60◦ to 146◦, which, as showed by population analysis, is associated with symmetric charge polarization and unique reactivity. By demonstrating the stability of fullerenes composed of pentagons and 3–7–8-carbon rings, this study revises traditional stability criteria, such as the isolated pentagon rule, and opens new avenues in fullerene research.

  • Energy Router: A Sustainable Solution for Future Residential Buildings
    • Mohammadreza Azizi
    • Oleksandr Husev
    • Rita Mbayed
    • Eric Monmasson
    • Joao Martins
    • Oleksandr Veligorskyi
    2025 IEEE Power Eelectronics Magazine

    Electric energy consumption is increasing much faster than the predicted growth in energy generation. Although the installed capacity of renewable energy sources is also expanding, grid congestion remains unavoidable without adopting smart energy management systems (EMS) and flexible power electronics structures. Given the significant installed capacity of photovoltaic (PV) systems in the residential sector, moving towards zero-emission buildings (ZEBs) through the use of storage systems and smart power electronics is essential. This article provides a detailed review of power electronics solutions for ZEBs and offers strategies to address related challenges. By exploring the promising future of the low-voltage dc (LVDC) industry in ZEBs, it presents and compares grid connection scenarios and evaluates their overall efficiencies across hybrid, dc, and ac technologies. Furthermore, it addresses the integration of dc and ac systems in energy resources (ER), proposing solutions for challenges related to protection, grounding, and leakage currents. Finally, it examines the latest EMS solutions, emphasizing the shift to full digitalization through a combination of cloud-based and edge-computing platforms.

  • Enhanced electrochemical capacitance of TiO2 nanotubes/MoSe2 composite obtained by hydrothermal route
    • Mariusz Szkoda
    • Anna Ilnicka
    2025 APPLIED SURFACE SCIENCE

    This study presents the hydrothermal synthesis of a novel TiO2 nanotubes/MoSe2 nanocomposite and investigates its enhanced electrochemical capacitance properties. The composite material was fabricated through a hydrothermal method, embedding MoSe2 onto TiO2 nanotubes. The resulting composite, termed Ti/TiO2/MoSe2, exhibited significantly improved electrochemical capacitance compared to TiO2 nanotubes alone. The synthesized composite was comprehensively characterized using solid-state physics techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). These analyses provided detailed insights into the structural and chemical composition of the TiO2/MoSe2 nanocomposite. The investigation revealed that the TiO2/MoSe2 nanocomposite displayed superior electrochemical performance, as determined by various electrochemical methods. Notably, the composite exhibited a capacitance approximately 10 times higher than that of pristine TiO2 nanotubes. These findings underscore the significant enhancement in energy storage capabilities achieved through the hydrothermal synthesis of TiO2/MoSe2. The observed enhancement in capacitance positions the TiO2/MoSe2 nanocomposite as a promising candidate for high-performance energy storage applications.

  • Enhanced electrochemical performance of sulfur-doped laser-induced graphene supercapacitors: Synergistic effects of doping and plasmochemical surface modification
    • Samaneh Shahsavarifar
    • Paweł Jakóbczyk
    • Anna Wcisło
    • Jacek Ryl
    • Robert Bogdanowicz
    2025 APPLIED SURFACE SCIENCE

    This work introduces a novel, scalable methodology for rapidly fabricating sulfur-doped laser-induced graphene with enhanced porosity and wetting characteristics, targeting advanced supercapacitor applications. An infrared laser scribing technique was employed to create a three-dimensional porous graphene network, with in-situ sulfur doping achieved through physical evaporation using powder precursor. A second-pass laser process ensured uniform sulfur integration and optimized graphene structure. Sulfur incorporation facilitated the formation of a hierarchical porous network, significantly improving hydrophilicity and surface chemistry. This modification enhanced ion transport and charge storage mechanisms through synergistic double-layer and pseudo-capacitance effects. Physicochemical characterization revealed a dramatically increased ID/IG ratio post-sulfur doping and plasma treatment, indicating increased crystal plane defects and promising capacitive properties. Systematic optimization of sulfur loading, synthesis temperature, and electrolyte composition yielded remarkable electrochemical performance. The optimized S-doped electrodes achieved a high areal capacitance of 30.18 mF/cm² at 0.08 mA/cm² using a PVA/H₂SO₄ gel electrolyte. Notably, the developed supercapacitors demonstrated mechanical flexibility, maintaining 84.7% of their initial capacitance after 5000 cycles, highlighting the potential for scalable, flexible energy storage technologies.

  • Enhanced Gain and Isolation Dual-Band Dual-Port MIMO Antenna with Integrated Lens for Millimeter-wave 5G Internet-of-Things Applications
    • Bilal Malik
    • Shahid Khan
    • Jamal Nasir
    • Sławomir Kozieł
    2025 Pełny tekst IEEE Access

    This paper proposes a dual-band dual-port Multiple Input Multiple Output (MIMO) antenna with enhanced gain and port isolation for 5G millimeter-wave (mm-wave) Internet of Things (IoT) applications. The gain enhancement is achieved using a 3D-printed dielectric lens integrated with the antenna, whereas port isolation is improved using a novel 2D compact metamaterial incorporated between the MIMO elements. The proposed integrated lens MIMO antenna (ILMA) design exhibits lower mutual coupling, low fabrication cost, and higher gain. At the same time, it uses a simple planar antenna feeding technique which features a small footprint compared to larger antenna arrays typically employed for gain enhancement. The overall size of the two-port integrated lens MIMO antenna is 19 × 29 × 13 mm3. The peak gain without dielectric lens is 6.5 dBi and 7.9 dBi at the two operating bands, which is further enhanced with a 3D-printed dielectric lens to 9.5 and 11.4 dBi at 26 GHz and 38 GHz, respectively. The proposed ILMA exhibits high isolation exceeding 30 dB and 22 dB at 26 GHz and 38 GHz. Experimental validation of the ILMA prototype corroborates the relevance of the assumed design approach. Compared to the MIMO antennas reported in the recent literature, the suggested integrated lens MIMO antenna not only offers a higher gain while maintaining a small footprint but also improves the isolation between the radiating elements. These features make the proposed design an attractive choice for mm-wave 5G internet-of-things (IoT) applications.

  • Enhanced sorption of inhibitory compounds from fermentation broth using a MOF@pseudo-DES composite
    • Zhila Honarmandrad
    • Seyed Soroush Mousavi Khadem
    • Karolina Kucharska
    • Massoud Kaykhaii
    • Justyna Łuczak
    • Jacek Gębicki
    2025 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS

    The increase in biorefinery processes underscores the need for effective biofuel generation; nevertheless, inhibitors such as hydroquinone (HQ), 5-hydroxymethylfurfural (HMF), furfural (FF), and vanillin (VAN) resulting from biomass degradation impede microbial growth and process efficiency. Herein, a deep eutectic solvent (DES)-like substance was in-situ generated on the surface of NH2-UiO-66 via a post-synthetic coating process using an amine-functionalized UiO-66 MOF and choline chloride (ChCl). ChCl, selected for its low cost and non-toxic properties as a hydrogen bond acceptor, enabled the formation of the thin layer of pseudo-DES on NH2-UiO-66 under solvent-free, thermal conditions, resulting in the composite material NH2-UiO-66@ pseudo-DES. The Zr6O4(OH)4 nodes and NH2 groups in NH2-UiO-66 are capable of forming robust hydrogen bonds with ChCl, enhancing the stability and functionality of the pseudo-DES coating. Various parameters influencing the removal efficiency, including pH, adsorbent amount, initial inhibitor concentration, and vortex time, were systematically investigated and optimized. Under the optimal conditions, the removal efficiency of HQ, HMF, FF, and VAN was 62.08%, 56.09%, 45.29%, and 83.46% respectively, for a synthetic sample. These values for real samples after hydrolysis and prior to fermentation were exceeded 51.73%, 53.21%, 42.69%, and 37.59%, for HQ, HMF, FF, and VAN, respectively. Inhibitor removal is driven by hydrogen bonding, electrostatic interactions, van der Waals forces, and π-π stacking with the inhibitors. This method demonstrates effective reusability for inhibitor removal up to four cycles. This groundbreaking research is the first of its kind to employ a MOF in conjunction with a pseudo-DES for this purpose; the results are simple, very effective, environmentally friendly, quick to react, and highly selective, making it ideal for biomass hydrolysis purification.

  • Enhancing Internal Cooling Channel Design in Inconel 718 Turbine Blades via Laser Powder Bed Fusion: A Comprehensive Review of Surface Topography Enhancements
    • Cho-pei Jiang
    • Masrurotin Masrurotin
    • Alvian Toto Wibisono
    • Wojciech Macek
    • Maziar Ramezani
    2025 International Journal of Precision Engineering and Manufacturing

    Inconel 718, a widely utilized Ni-based superalloy in the aerospace industry, is renowned for its exceptional mechanical properties, high-temperature corrosion resistance, and thermal stability, making it an ideal material for turbine blades operating under extreme conditions of up to 2200 °C and high-pressure. Traditional single crystal casting, the prevalent manufacturing method for turbine blades, poses inflexibility challenges. Laser Powder Bed Fusion Additive Manufacturing (LPBF-AM) emerges as a disruptive alternative, providing flexibility and intricate design possibilities. However, LPBF-fabricated turbine blades face challenges, notably low thermal stability due to the polycrystalline microstructure. To address this, implementing an internal cooling channel to the turbine blade geometry can overcome this challenge. The flow of cooling fluid inside the cooling channel absorbs the heat of turbine, and maintains the turbine at low-temperature. The performance of internal cooling channel can be improved by implementing controllable surface texture to provide the heat sink mechanism. Nowadays, the LPBF has opportunity to fabricate the complex geometry of turbine blade with surface-textured internal cooling channel. This review delves into the specific requirements for the next generation of turbine blades featuring surface-textured internal cooling channels. It covers considerations such as geometric design, LPBF parameters, metallurgical aspects of processing Inconel 718, and quality testing encompassing material properties and geometric accuracy. Additionally, the review outlines existing challenges and research prospects in LPBF of Inconel 718 for advancing turbine blade components. In conclusion, the review inspires further development in high-performance Inconel 718 turbine blades, emphasizing advancements in surface textures and internal cooling channels via LPBF.

  • Estimation of grasp type and determining grasping points for Adaptive Grasping Device
    • Michał Czubenko
    • Piotr Łyczko
    • Rafał Okuński
    2025 Archives of Control Sciences

    The article describes the grasping point algorithm (GPA), aimed to determine points for picking up objects by a manipulator equipped with a proprietary gripper enabling three picking modes (suction cup, two fingers, three fingers). The paper outlines the topic of unknown object picking using various types of grippers, both from a stack of objects and stand-alone items. It describes details of four methods available in the literature. Presented GPA algorithm consists of four separate functions dedicated to appropriate grasping methods chosen based on a decision-making process. The dedicated functions has been described in detail and tested. Used methods have been tested manually on 15 different objects. GPA algorithm has been evaluated in realworld tests as well. The presented tests showed efficiency of approximately 92% in the case of moving previously unknown objects from the stack to the target cuvette.

  • European Green Deal Index: a new composite tool for monitoring European Union’s Green Deal strategy
    • Magdalena Olczyk
    • Marta Kuc-Czarnecka
    2025 JOURNAL OF CLEANER PRODUCTION

    The European Union’s growth strategy, called "The European Green Deal," strives to create a competitive economy in which there are no net emissions of greenhouse gases in 2050 and growth is decoupled from resource use. This paper aims to develop a new composite indicator, the European Green Deal Index, to analyse the implementation of the European Green Deal in the Member States. This index is based on 26 indicators proposed by the European Commission, categorised under the three pillars of reducing climate impact, protecting our planet and our health, and enabling green and just transition. The new index makes possible to identify the leading and lagging countries as well as the convergence/divergence between European Union countries on their path towards a zero-emission and climate-neutral economy. We employ a sensitivity analysis to compute the European Green Deal Index. Our analysis shows that the high complexity of the European Green Deal strategy poses a major challenge for most European Union countries to achieve all Green Deal targets. According to the value of the European Green Deal Index, Estonia, Sweden, and Latvia, as well as Austria, are leading countries, suggesting that North European paths toward a green economy are the most suitable approach for implementing the European Green Deal. Our analysis revealed a slight upward divergence in European Green Deal values among Member States. When analysing the development of the paths to achieving the Green Deal targets, we find that France, the Netherlands, and Germany are among the frontrunners with an above-average paths.

  • Evaluating oxide nanoparticle exsolution on A-site deficient PrBaCo2O6-δ electrodes
    • Alfonso Carrillo
    • Maria Balaguer
    • Cecilia Solís
    • Andrés López-García
    • Sylvio Haas
    • María Fabuel
    • Blanca Delgado-Galicia
    • Isabelle Rodriguez
    • Einar Vøllestad
    • Sebastian Wachowski
    • Ragnar Strandbakke
    • Jose M. Serra
    • Truls Norby
    2025 Pełny tekst Journal of Physics-Energy

    Nanoparticle exsolution is a powerful technique for functionalizing redox oxides in energy applications, particularly at high temperatures. It shows promise for solid oxide fuel cells and electrolyzers. However, exsolution of other chemistries like metal oxides is not well studied, and the mechanism is poorly understood. This work explores oxide exsolution in PrBa1−xCo2O6−δ (x = 0, 0.05, 0.1, 0.15) double perovskites, practiced electrodes in proton ceramic fuel cells and electrolyzers. Oxide exsolution in PrBa1−xCo2O6−δ aimed at boosting the electrocatalytic activity and was evaluated by varying intrinsic materials-related properties, viz. A-site deficiency and external parameters (temperature, under fixed time, and pO2 = 10−5 atm conditions). The materials were analyzed with conventional characterization tools and synchrotron-based small-angle x-ray scattering. Unlike metal-nanoparticle exsolution, increasing the A-site deficiency did not enhance the extent of oxide-nanoparticle exsolution, whereas larger nanoparticles were obtained by increasing the exsolution temperature. Combined Raman spectroscopy and electron microscopy analysis revealed that BaCoO3, Co3O4, and amorphous BaCO3 nanoparticles were formed on the surface of the double perovskites after the reductive treatments. The present results demonstrate the complexity of oxide-nanoparticle exsolution in comparison with metal-nanoparticle exsolution. Further materials screening and mechanistic studies are needed to enhance our understanding of this method for functionalizing proton ceramic electrochemical cells (PCEC) electrodes.

  • Evaluation of overstrength-based interaction checks for columns in steel moment frames
    • Tomasz Falborski
    • Greta Murtas
    • Ahmed Elkady
    • Dimitrios Lignos
    • Amit Kanvinde
    2025 JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH

    Current design guidelines in the United States require a check for only column axial force under overstrength seismic loads for capacity-designed steel moment frames. A study is presented to examine the implications of this guidance, which disregards the column interaction check (including both axial force and moment) under overstrength seismic loads. A set of thirteen steel moment frames are designed using multiple rules that apply and disregard overstrength, drift, and cross-sectional compactness checks in various combinations. The frames are subjected to a suite of simulations including linear elastic, nonlinear static pushover, nonlinear response history, and continuum finite element simulations that are able to represent a range of physical behavior modes in the columns including interactive nonlinear geometric instabilities that could trigger loss of the load carrying capacity of the member. The simulations indicate no significant distinction between the seismic performance of steel moment resisting frames designed as per current code-based provisions (i.e., disregarding the column interaction check for overstrength seismic loads), and those designed with the use of the interaction check, with each providing acceptable response without failure. The simulations also indicate that design checks for drift and cross-sectional compactness play a significant role ensuring acceptable response, providing additional margin of safety beyond the member strength checks.

  • Evaluation of Selected Modulation Techniques in Underwater Multipath Channel
    • Agnieszka Czapiewska
    • Andrzej Łuksza
    • Ryszard Studański
    • Łukasz Wojewódka
    • Andrzej Żak
    2025 IEEE Access

    There is a growing interest in the use of Autonomous Underwater Vehicles (AUVs) and Underwater Sensor Networks (USNs) for scientific, military, and industrial applications, leading to the development of wireless underwater communications. However, the channel for Underwater Acoustic (UWA) communications is challenging compared to the radio wave propagation in the air. Especially in shallow waters, where the channel has strong multipath effects. The difficulties are even greater when the communicating objects are in motion. Nevertheless, it is worth to analyze if solutions known from radio communication systems are applicable for underwater hydroacoustic purposes. In this paper, a comparison is made between two well-known modulation techniques used in radio communication: the widely used BPSK (Binary Phase Shift Keying) modulation and CSS (Chirp Spread Spectrum) technique used in LoRa (Long Range communication) system. The modulation techniques mentioned are compared with MBFSK (Multiple Binary Frequency Shift Keying) modulation used in underwater wireless communication systems, which is said to be very resistant to the multipath effect. In MBFSK, the value of the bit determines the value of the frequency on which the power is transmitted. The paper presents simulation results as well as results of measurements in the towing tank of the CTO (Maritime Advanced Research Centre). The comparison of simulation and real measurements leads to worrying conclusions, as they differ considerably.

  • Evaluation of the Variability of Vibration Measurement Results in Rolling Bearing Quality Control
    • Paweł Zmarzły
    • Mateusz Wrzochal
    • Stanisław Adamczak
    2025 Applied Sciences-Basel

    The final result of rolling bearing quality control is influenced by many factors that are not always taken into account. If non-conforming products leave the factory, then the reliability of equipment containing rolling bearings is significantly weakened. The paper presents an analysis of the reasons for the variability of vibration measurement results in rolling bearing quality control. The paper describes the organisation of rolling bearing acceptance inspection on the production line and its place in the rolling bearing production process. The study evaluates the influence of the measuring device and the location of the sensor on the result of the rolling bearing vibration monitoring process. The problem of repeatability and reproducibility of rolling bearing vibration measurement was also investigated. On the basis of the obtained results, conclusions were drawn regarding the improvement of the quality control process of rolling bearings in production plants.

  • Excited states of mono- and biruthenium(II) complexes adsorbed on nanocrystalline titanium dioxide studied by electroabsorption spectroscopy
    • Daniel Karol Pelczarski
    • Błażej Gierczyk
    • Maciej Zalas
    • Małgorzata Makowska-janusik
    • Waldemar Stampor
    2025 Scientific Reports

    Comprehensive characterization of the lowest energy electronic excited states for mono- and binuclear Ru(II) complexes containing bipyridine ligands has been performed by electroabsorption (EA) spectroscopy. The EA spectra of Ru complexes sensitizing a TiO2 semiconductor were compared with the spectra of these complexes in the form of solid neat films, both of which parametrized within the Liptay theory. The extracted values of relevant parameters, relating to molecular dipoles after optical MLCT (metal-to-ligand-charge-transfer) excitation, exhibit a clearly noticeable increase for Ru complexes adsorbed on TiO2, but they are too small to be attributed to excitation associated with the direct transfer of an electron from the dye adsorbate to the TiO2 semiconductor. Due to the difficulties arising from standard analysis based on Liptay formalism, we have for the first time successfully reproduced the EA spectra of the Ru/TiO2 systems using the time-dependent density functional (TDDFT) calculations, incorporating into the Hamiltonian a term describing the interaction of a molecule with the local electric field it experiences from the TiO2 structure and the neighboring Ru complex molecules, without additional assumptions about the lineshape of the EA signal. The implications of these results are briefly discussed in the context of dye-sensitized solar cells.

  • Exergy analysis and thermodynamic optimization of a bioenergy with carbon capture and storage gas power plant using Monte Carlo simulation of sewage sludge composition
    • Kamil Stasiak
    • Ivar Ståle Ertesvåg
    • Paweł Ziółkowski
    • Dariusz Mikielewicz
    2025 APPLIED THERMAL ENGINEERING

    An exergy analysis is performed on the negative CO2 emission gas power plant (nCO2PP), which integrates the fuel preparation, power generation and carbon capture process sections. The cycle is modeled in Aspen Plus coupled with REFPROP, combining deterministic and Monte Carlo stochastic approaches, the latter being a novelty in this work. In all cases studied, the simulations maintain the complex thermodynamic relationships. Exergy losses with areas of potential improvement are identified, while Monte Carlo simulation in Python generates sewage sludge composition, improving cycle realism. In the deterministic approach, the exergies are calculated for a single sewage sludge composition under ambient air conditions with relative humidity of 40 %, 50 % (base case) and 60 % and CO2 air concentration of 375 ppm, 417 ppm (base case) and 1000 ppm, representing a worst case scenario of CO2 increase until the year 2100. For the deterministic base case nCO2PP, the largest exergy losses are observed in the wet combustion chamber (127 kW, 62 % efficiency), gasification process (43 kW, 89 % efficiency), and water condensation in the gas scrubber (43 kW, 87 % efficiency), while the nCO2PP exergy efficiency, related to the chemical exergy of the sewage sludge, is 33.3 %. Sensitivity analysis on turbine vacuum and spray-ejector condenser suction pressure results in an increase of the nCO2PP efficiency by 0.3 % to 33.6 %. Monte Carlo results are incorporated into the Aspen Plus model after the base case optimization. These yield in a range of nCO2PP exergy efficiencies from 33.6 % to 39.7 % with a mean of 37.5 %.

  • Experimental, Analytical, and Numerical Analyses of Slurry Erosion Resistance of Austenitic 1.4301 Stainless Steel
    • Dominika Zakrzewska
    • Marta H. Buszko
    2025 JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME

    The degradation of 1.4301 (AISI 304, X5CrNi18-10) stainless steel with two different impact angles (30 deg and 90 deg) has been investigated using a slurry pot tester. Spherical solid particles were used in the experiment. The impact angle significantly influenced the erosion resistance of 1.4301 steel. Tests conducted at an impact angle of 30 deg showed a higher erosion rate of approximately 91%. The test results showed that with a normal impact angle, the final and subsurface hardness were higher. Numerical analyses of contact stresses were carried out based on Hertz’s theory. The calculation results were compared with the simulation results, showing a low error level (0.70–4.63%), depending on the analyzed parameter, i.e., Hertzian stress or maximum shear stress. The numerical results confirm the significant dependence of the erosion resistance on the impact angle. It has been found that the tallest peak height decreased with increasing hardness and impact angle. Scanning electron microscopic analysis showed that after the erosion tests, indentations, craters, microcutting, and microploughing were observed.

  • Experimental and numerical study of free convective heat transfer in air performed simultaneously from the upper and lower surfaces of a horizontal plate heated on both sides
    • Michał Ryms
    • Krzysztof Tesch
    • Witold Lewandowski
    2025 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER

    This paper presents an experimental study, supported by numerical analysis, on convective heat transfer in air from a newly designed, horizontal, double-sided heated Type II plate. Unlike the single-sided heated Type I plate, where the heating surface faces either upwards or downwards, the Type II plate heats both surfaces simultaneously. The tested plate was constructed from three glued laminates, each 0.6 mm thick, resulting in a total thickness of 2.1 mm. Minimal lateral-surface heat loss (<4.2%) ensured high measurement accuracy. Surface resistance thermometers (Tlow/up) were etched into the copper layer on one side, while two resistance heaters (Nlow/up) were embedded in the copper-coated middle laminate. Numerical calculations (Num.II and Num.I) for Type II and I plates revealed discrepancies under the UWT (Uniform Wall Temperature) condition: CExp.II/CNum.II = 33.8% (upper) and -8.4% (lower), and for UHF (Uniform Heat Flux): 17.8% (upper) and 6.1% (lower). Similar discrepancies in CNum.II/ CNum.I (-36.1% UWTup, 0.5% UWTlow, -26.9% UHFup, 0.7% UHFlow) confirmed different heat transfer mechanisms on the upper heating surfaces of Type II and I plates. In the absence of the mean literature correlation (MLC.II) for Type II plates, numerical verification (CNum.II) was conducted, yielding CExp./CNum.II = 1.338 (upper) and 0.916 (lower) for UWT, and 1.178 (upper) and 1.061 (lower) for UHF. Indirect verification using Type I plate data (MLC.I) required numerical transformation, yielding CExp.II/CMLC.I = 1.426 (upper) and 0.748 (lower) for UWT, and 1.017 (upper) and 0.896 (lower) for UHF. These results confirm the reliability of the Type II plate tests.

  • Experimental and Theoretical Study on Electron Interactions with Acetic Acid Molecules
    • Natalia Tańska
    • Kuba Wójcik
    • Thiago Corrêa Freitas
    • Márcio H F Bettega
    • Czesław Szmytkowski
    • Paweł Możejko
    2025 JOURNAL OF PHYSICAL CHEMISTRY A

    The absolute total cross section for electron collisions with acetic acid has been measured using an electrostatic electron spectrometerand linear transmission method for collision energies ranging from 0.4 to 300eV. Elastic electron scattering from acetic acid within a low-energy range has also been studied theoretically using the Schwinger multichannel and R-matrix methods, in the static-exchange and static-exchange plus polarization levels of approximation for energies up to 15 eV. The absolute total and the integralelastic cross sections display a π* shape resonance at around 1.7 eV and abroad structure spanned between 4 and 10 eV, which can be associated with a superposition of overlapping σ* resonances. We compared the obtained results with data available in the literature regarding the interaction ofelectrons with acetic acid. The results of electron collisions with acetic acid,methyl formate, and formic acid are also compared and discussed.

  • Experimental evidence of the excited-state mixing in the blue emitter for organic light-emitting diodes
    • Vladyslav Ievtukhov
    • Michał Mońka
    • Olga Ciupak
    • Irena Bylińska
    • Piotr Bojarski
    • Karol Krzymiński
    • Illia E. Serdiuk
    2025 Journal of Materials Chemistry C

    High hopes have been placed on organic emitters, which are supposed to solve the problem of low stability of blue OLEDs. A peculiar phenomenon of thermally activated delayed fluorescence (TADF), which brought such emitters to the range of the top-studied materials for organic optoelectronics within the last decade, remains poorly understood. Here, we report the results of comprehensive photophysical studies of one of the most successful candidates for blue TADF OLEDs, the TMCz-BO emitter (9-(5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)-1,3,6,8-tetramethyl-9H-carbazole) characterised by outstanding triplet-harvesting properties. One of the main aims of this work is to understand the reason for these unique properties. Steady-state and time-resolved spectroscopic investigations in media of various polarity, viscosity, and temperature reveal that at least five excited states of different characters and multiplicity are responsible for the emissive and spin–flip transitions in the TMCz-BO molecular systems. First of all, in contrast to typical donor–acceptor TADF emitters, the S1 state of TMCz-BO does not have a pure charge-transfer character but shows a considerable contribution of the locally-excited state of the acceptor fragment, which provides a fast radiative rate. The T1 state is a superposition of two locally excited and one charge-transfer states, providing reasonable spin–orbit coupling. Regarding the TADF mechanism in various media, reverse intersystem crossing follows the T1 - S1 model, considering the excited-state mixing, a notion introduced here to explain the triple and dual nature of the respective states. Such a mixing is dynamic in low-viscosity solutions due to low barriers for molecular vibrations. In films with a host matrix, a static excited-state mixing occurs, assisted by the low-amplitude vibrations within the local energetic minimum of the emitting species. The high efficiency of the excited-state mixing in TMCz-BO is explained by the rigid structure of its donor and acceptor fragments and their limited but still active mutual rotations. This provides negligible structural differences between various electronic states, enabling low reorganisation energies favourable for radiative and spin–flip processes while maintaining vibrational activation of spin–orbit coupling. Despite a lower reverse intersystem crossing rate in media of high viscosity, TMCz-BO shows rare near-UV TADF in films with the non-polar host.

  • Experimental research and numerical modelling of mode I fracture initiation in notched polycarbonate specimens
    • Elżbieta Bura
    • Jakub Augustyniak
    • Andrzej Seweryn
    2025 THEORETICAL AND APPLIED FRACTURE MECHANICS

    In this paper the results of experimental data from fracture test and numerical calculations under critical loading (at the moment of crack initiation) were presented. The polycarbonate specimens were subjected to tension. The flat notched elements (V-type edge notches with different root radii: 0.1, 0.5, 2 and 10 mm) were made in two thicknesses: 5 and 15 mm. The ARAMIS 3D 4 M vision system for non-contact displacement measurements, was used to record the elongation of the measurement base. During the tests, PHANTOM cameras were also used, allowing the precise indication of the crack initiation moment and, consequently, a more accurate estimation of measured values: the critical tensile force and specimen elongation. The microscopic observations were used to indicate the sites of crack initiation. The different characteristics of the polycarbonate fracture process, which were determined by specimens thickness and notch root radii. The reasons for these differences are described. The numerical calculation using finite element method were carried. Depending on the fracture type, possible stress-strain relationships for use in predicting critical loading are indicated. The main motivation for conducting the research described in the manuscript is to understand the nature of the fracture phenomenon occurring in polycarbonate (PC). This material is widely used in engineering practice and its properties at different operating parameters vary, the fracture process itself can be brittle or ductile. The manuscript attempts to answer the questions of how the geometrical parameters of notched specimens affect the initiation of fracture, i.e. when and where it occurs. Knowing this process allows the formulation of tools for predicting critical loading conditions, an important step in engineering design.

  • Experimental study of the effect of seawater and temperature on the corrosion resistance of cement composites with the addition of copper post-flotation waste
    • Szymon Kalisz
    • Elżbieta Haustein
    • Marek Lieder
    2025 Scientific Reports

    The presented results of the study concern the determination of corrosion resistance of cement composites with the copper post-flotation waste (PFW) as a cement substitute in the amounts of 2.5%, 5.0%, 7.5%, and 10%, exposed to seawater, depending on the temperature (10°C and 20°C). To better evaluate and understand the compressive strength, the hydration products of the cement composites were analyzed after exposure to seawater at 28 and 360 days by TGA and XRD methods. The cement composites incorporating test material exhibited corrosion resistance in seawater, with samples containing 5 wt% PFW achieved the highest compressive strength of 69.7 MPa (at 20°C) and 68.9 MPa (at 10°C) after 360 days of immersion in seawater. The obtained results were higher by 27.9% and 3.6% compared to the control samples. The tests (360 days) showed the possibility of using copper as a post-flotation waste additive in up to 5% of cement mass without significant changes to cement composites’ mechanical and chemical properties. The research results indicate the potential possibility of waste used in construction, which would not only allow for a significant reduction in the production costs of cement, including a reduction in CO2 emissions, but above all, would eliminate the risk of its negative impact on the natural environment.

  • Expert system against machine learning approaches as a virtual sensor for ventricular arrhythmia risk level estimation
    • Sebastián García-Galán
    • Jose A. Cabrera-Rodriguez
    • Francisco Javier Maldonado-Carrascosa
    • Nicolás Ruiz-Reyes
    • Małgorzata Szczerska
    • Pedro Vera-Candeas
    • Francisco D. Gonzalez-Martinez
    • Francisco J. Canadas-Quesada
    • Alfonso J. Cruz-Lendinez
    2025 Biomedical Signal Processing and Control

    Recent advancements in machine learning have opened new avenues for preventing fatal ventricular arrhythmia by accurately measuring and analyzing QT intervals. This paper presents virtual sensor based on an expert system designed to prevent the risk of fatal ventricular arrhythmias associated with QT-prolonging treatments. The expert system categorizes patients into three risk levels based on their electrocardiogram-derived QT intervals and other clinical data, such as age or sex, facilitating informed decision-making and reducing the workload for healthcare professionals. Expert systems, known for their effectiveness in classifications with limited data, are particularly advantageous in this context. They not only achieve better standard metrics but also offer interpretability that other machine learning models lack. The proposed system’s performance has been rigorously compared against various machine learning algorithms, demonstrating superior efficiency as evidenced by confusion matrices, standard classification metrics, and receiver operation point curves. With an accuracy of 96.5%, the expert system proves to be the best option among the models evaluated, optimizing patient care and treatment outcomes by enabling more frequent and precise electrocardiogram assessments.

  • Exploration of Behavioral Patterns and Cognitive Biases among Stock Market Investors
    • Maciej Tkacz
    • Celina Olszak
    • Jozef Zurada
    • Paweł Weichbroth
    2025 Pełny tekst

    This study aims to explore behavioral patterns and cognitive biases among stock market investors. By analyzing investor behavior through a stock market simulator, the research seeks to understand the impact of cognitive biases on investment decisions. The methodology encompasses a detailed analysis of transaction data to identify prevalent patterns and biases. Findings suggest that biases such as overconfidence, representativeness heuristic, gambler’s fallacy, and herd mentality significantly influence investor behavior.

  • Exploring Cu-oxide and Mn-oxide impregnated biochar nanocomposites for sustainable chromium removal from water: Reusability and kinetic studies
    • Rizwan Tariq
    • Muhammad Imran
    • Muhammad Nadeem
    • Behzad Murtaza
    • Jibran Iqbal
    • Noor S. Shah
    • Muhammad Amjad
    • Sajjad Ahmad
    • Łukasz Cichocki
    2025 CHEMICAL ENGINEERING SCIENCE

    The present study aims to evaluate the potential of Sesbania bispinosa biochar (SBBC) and its nanocomposites, SBBC/Mn-oxide, SBBC/Cu-oxide and SBBC/Mn-oxide/Cu-oxide for Cr removal from contaminated water. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and point of zero charge (PZC) were employed. Impact of initial Cr concentration (25–200 mg/L), pH levels (2–8), adsorbent dose (1–3 g/L), contact time (15–180 min), and coexisting ions in water were investigated. The highest Cr adsorption (75 mg/g) was achieved with triple nanocomposite (SBBC/Mn-oxide/Cuoxide), followed by dual SBBC/Cu-oxide (59.65 mg/g), SBBC/Mn-oxide (44.9 mg/g) composites, and SBBC alone (37.4 mg/g). The coexisting ions showed a decline in Cr removal. Reusability results revealed a slightly lower Cr removal (8 %) with SBBC/Mn-oxide/Cu-oxide nanocomposite in the fifth cycle. The experimental adsorption data were well-explained through Freundlich and pseudo-second-order kinetic models. It is concluded that nanoparticle-biochar composites are effective for remediating Cr-contaminated water.

  • Fatigue Damage Evolution in SS316L Produced by Powder Bed Fusion in Different Orientations with Reused Powder Feedstock
    • Mateusz Kopec
    • U. Gunputh
    • G. Williams
    • Wojciech Macek
    • Zbigniew Kowalewski
    • Paul Wood
    2025 Pełny tekst EXPERIMENTAL MECHANICS

    Background Metal Laser Powder Bed Fusion Melting (LPBF-M) is considered economically viable and environmentally sustainable because of the possibility of reusing the residual powder feedstock leftover in the build chamber after a part build is completed. There is however limited information on the fatigue damage development of LPBF-M samples made from reused feedstock. Objective In this paper, the stainless steel 316 L (SS316L) powder feedstock was examined and characterised after 25 reuses, following which the fatigue damage development of material samples made from the reused powder was assessed. Methods The suitability of the powder to LPBF-M technology was evaluated by microstructural observations and measurements of Hall flow, apparent and tapped density as well as Carr’s Index and Hausner ratio. LPBF-M bar samples in three build orientations (Z – vertical, XY – horizontal, ZX – 45° from the build plate) were built for fatigue testing. They were then subjected to fatigue testing under load control using full tension and compression cyclic loading and stress asymmetry coefficient equal to -1 in the range of stress amplitude from ± 300 MPa to ± 500 MPa. Results Samples made from reused powder (25 times) in the LPBF-M process exhibited similar fatigue performance to fresh unused powder although a lower ductility for vertical samples was observed during tensile testing. Printing in horizontal (XY) and diagonal (ZX) directions, with reused powder, improved the service life of the SS316L alloy in comparison to the vertical (Z). Conclusions Over the 25 reuses of the powder feedstock there was no measurable difference in the flowability between the fresh (Hall Flow: 21.4 s/50 g) and reused powder (Hall Flow: 20.6 s/50 g). This confirms a uniform and stable powder feeding process during LPBF-M for both fresh and reused powder. The analysis of fatigue damage parameter, D, concluded cyclic plasticity and ratcheting to be the main mechanism of damage.

  • Feminist Lens on Gender Roles in Entrepreneurial Intention and Implementation
    • Julita Wasilczuk
    • Jakub Golik
    2025 Gender, Work and Organization

    Based on Social Feminist Theory, Post-Structural Feminism and Gender-Role Orientation (GRO) (masculinity, femininity and androgyny), the aim of this research is to study the entrepreneurial process through the lenses of both biological sex and socially constructed gender, in order to disentangle their effects and to shed new light on the process. Secondly, we aim to push forward the research on the early-stage entrepreneurial process by going beyond entrepreneurial intention. We achieve this by including the entrepreneurial implementation intention construct as an important intermediate step between intention and actual action, thus filling the intention-action gap. We propose a model of the entrepreneurial process consisting of four ordered elements, namely: general risk propensity, entrepreneurial self-efficacy, entrepreneurial intention, and entrepreneurial implementation intention. In order to verify the model and to investigate the influence of gender-role orientations on each of the model’s constituents, we employ Structural Equation Modelling. Additionally, we use Multigroup Analysis to compare males and females. This is done on a group of more than 670 students from technical universities. Our research empirically confirms the proposed model of the entrepreneurial process. Biological sex influences risk propensity and entrepreneurial intention, while having no impact on entrepreneurial self-efficacy and entrepreneurial implementation intention. Using GRO provides more insight as we observe that among all individuals masculine GRO reinforces all elements of the entrepreneurial process, while feminine GRO does not, with the exception of perceived risk propensity, but only among females. Finally, androgynous GRO has the most varied effect out of all three GROs. Both theoretical approaches explain the lower entrepreneurial intentions of women, which are due to early socialisation and experiences shaping social gender, as well as the attribution of entrepreneurship to the male sphere of activity. Finally, our study shows that using both biological sex and social gender concurrently provides more insights.

  • FeS-based nanocomposites: A promising approach for sustainable environmental remediation – Focus on adsorption and photocatalysis – A review
    • Aqsa Nawaz
    • Aman Khalid
    • Wajeeha Qayyum
    • Rabia Bibi
    • Muhammad Azam Qamar
    • Muhammad Zahid
    • Ahmad Farhan
    • Manoj P Rayaroth
    • Łukasz Cichocki
    • Grzegorz Boczkaj
    2025 JOURNAL OF ENVIRONMENTAL MANAGEMENT

    Population expansion, industrialization, urban development, and climate changes increased the water crisis in terms of drinking water availability. Among the various nanomaterials for nanoremediation towards water treatment, FeS-based nanocomposites have emerged as promising candidates in the adsorptive and photocatalytic removal of contaminants. This paper, therefore, evaluates the potential of FeS-based nanocomposites for environmental applications, more specifically the combined use of adsorption and photocatalysis. Pyrite and mackinawite structures outcompeted the other FeS configurations due to their large surface areas, numerous active sites, and enhanced conductivity, factors that enhance the adsorption and photovoltaic processes. To improve photocatalytic performance FeS requires modification with additional materials. Various fabrication strategies (including hydrothermal method, co-precipitation, electrochemical anodization, electrospinning, impregnation, green synthesis, mechanochemical approach/ball milling) of FeS-based composites and their efficacy and the mechanisms for removing organic and inorganic pollutants are reviewed in this paper. The structural characteristics of FeS scaffolds play a crucial role in the effective removal of heavy metals, such as Hg and Cr ions, primarily through ion exchange and surface complexation. Organic pollutants such as methylene blue and tetracycline were effectively degraded by advanced oxidation processes (AOPs). A large scale applications of FeS include industrial wastewater treatment, groundwater remediation towards trichloroethylene and other organic solvents removal, municipal wastewater, oil spills cleanup, pre-treatment for seawater desalination. Current challenges relate to catalysts stability, their removal after treatment stage, recycling, metals leaching and up-scaling as well as high effectiveness in real case-scenario and costs optimization. In summary, this review will help to advance research in the field of environmental remediation using FeS-based nanocomposites.

  • Finite Element Analysis of Occupant Risk in Vehicular Impacts into Cluster Mailboxes
    • Emre Palta
    • Łukasz Pachocki
    • Dawid Bruski
    • Qian Wang
    • Christopher Jaus
    • Howie Fang
    2025 Pełny tekst Computation

    The deployment of cluster mailboxes (CMs) in the U.S. has raised safety concerns for passengers in potential vehicular crashes involving CMs. This study investigated the crashworthiness of two types of CMs through nonlinear finite element simulations. Two configurations of CM arrangements were considered: a single- and a dual-unit setup. These CM designs were tested on flat-road conditions with and without a curb. A 2010 Toyota Yaris and a 2006 Ford F250, both in compliance with the Manual for Assessing Safety Hardware (MASH), were employed in the analysis. The simulations incorporated airbag models, seatbelt restraint systems, and a Hybrid III 50th percentile adult male dummy. The investigations focused on evaluating the safety of vehicle occupants in 32 impact scenarios and under MASH Test Level 1 conditions (with an impact speed of 50 km/h). The simulation results provided insights into occupant risk and determined the primary failure mode of the CMs. No components of the mailboxes were found intruding into the vehicle’s occupant compartment. For all considered cases, the safety factors remained within allowable limits, indicating only a marginal risk of potential injury to occupants posed by the considered CMs.

  • First truly deep eutectic solvent (DES) based stationary phase for high-performance liquid chromatography (HPLC)
    • Mateusz Marchel
    • Andrzej Przyjazny
    • Grzegorz Boczkaj
    2025 TALANTA.The International Journal of Pure and Applied Analytical Chemistry

    Deep eutectic solvents (DESs) have gained significant attention due to their environmentally friendly properties and versatile applications in various fields, including analytical chemistry. This study investigates the use of a deep eutectic solvent (DES) composed of l-proline protonated with hydrochloric acid and xylitol as a surface modifier for silica-based stationary phases in high-performance liquid chromatography (HPLC). The DES was successfully immobilized on silica, and its impact on chromatographic performance was evaluated in normal-phase liquid chromatography (NP-HPLC). It was observed that DES immobilized layer acted as a real liquid stationary phase. The DES-modified columns exhibited improved selectivity, resolution for polar analytes, and shorter retention times for non-polar compounds compared to unmodified silica columns. Additionally, the DES-modified phase demonstrated long-term stability over multiple chromatographic cycles. These results highlight the potential of DESs as customizable, environmentally friendly stationary phase modifiers for enhancing chromatographic efficiency and selectivity, particularly in separating polar analytes, opening new avenues for the development of advanced chromatographic materials and contributing to greener and more efficient separation techniques. The robust preparation method also facilitates easy scalability for large-scale applications, such as the isolation of valuable compounds and the purification of complex mixtures, including phenols, amines, and nitro-derivatives.

  • Flexibility in PAM recognition expands DNA targeting in xCas9
    • Kazi A Hossain
    • Łukasz Nierzwicki
    • Modesto Orozco
    • Jacek Czub
    • Giulia Palermo
    2025 Pełny tekst eLife

    xCas9 is an evolved variant of the CRISPR-Cas9 genome editing system, engineered to improve specificity and reduce undesired off-target effects. How xCas9 expands the DNA targeting capability of Cas9 by recognising a series of alternative protospacer adjacent motif (PAM) sequences while ignoring others is unknown. Here, we elucidate the molecular mechanism underlying xCas9’s expanded PAM recognition and provide critical insights for expanding DNA targeting. We demonstrate that while wild-type Cas9 enforces stringent guanine selection through the rigidity of its interacting arginine dyad, xCas9 introduces flexibility in R1335, enabling selective recognition of specific PAM sequences. This increased flexibility confers a pronounced entropic preference, which also improves recognition of the canonical TGG PAM. Furthermore, xCas9 enhances DNA binding to alternative PAM sequences during the early evolution cycles, while favouring binding to the canonical PAM in the final evolution cycle. This dual functionality highlights how xCas9 broadens PAM recognition and underscores the importance of fine-tuning the flexibility of the PAM-interacting cleft as a key strategy for expanding the DNA targeting potential of CRISPR-Cas systems. These findings deepen our understanding of DNA recognition in xCas9 and may apply to other CRISPR-Cas systems with similar PAM recognition requirements.

  • Fluoride-induced stress shapes partial denitrification granules to sustain microbial metabolism
    • Shenbin Cao
    • Jinxin Fang
    • Konrad Koch
    • Xiaoyan Fan
    • Hussein Al-Hazmi
    • Rui Du
    • George F Wells
    2025 WATER RESEARCH

    The presence of fluoride ions (F-) in nitrogen-rich wastewater from photovoltaic and semiconductor industries introduces a significant challenge to biological treatment processes, particularly for the innovative partial denitrification (PD) process, which supplies nitrite for anaerobic ammonium oxidation (Anammox). This study provides the first comprehensive and systematic investigation of the effects of F- stress on the granule-based PD process through batch tests and long-term operation. Results indicate that PD activity remains resilient to F- shock up to 1.5 g/L but is markedly impaired at concentrations of 2.0–3.0 g/L, despite maintaining a nitrate-to-nitrite transformation ratio (NTR) of approximately 80 %. Under long-term F- stress at 0.5 g/L, NTR gradually reduces to 50 %, but subsequently recovers to and maintains at 70 %. The increased secretion of loosely bound extracellular polymeric substances and proteins likely enhances the resistance of PD granules to F- stress, though excessive amounts degrade their settling properties. F--induced microbial community succession shapes a predominance of medium granules (1.0 < d < 2.0 mm of 60.2 %) by enhancing aggregation of smaller granules and disintegration of larger ones. This enhances the mechanical strength and microbial activity of PD granules, aiding in resistance to F- stress to sustain microbial metabolism. Thauera is selectively enriched under long-term F- stress, with upregulated nirBDS genes contributing to the reduced NTR. Additionally, increased electron metabolism activity and a robust antioxidative response help to maintain higher microbial metabolic activity, mitigating F--induced oxidative stress. These findings advance our understanding of the resilience and adaptability of the PD process under F- stress, providing critical insights for optimizing biological wastewater treatment systems in challenging environments.

  • Fluvial ecology disasters: the impact of the Gliwice Canal on the ecological crisis in the Oder River basin, Poland (2022)
    • Marek Ruman
    • Natalia Janczewska
    • Klaudia Kosek
    • Wojciech Artichowicz
    • Magdalena Nasiek
    • Magdalena Matysik
    2025 Acta Geophysica

    In August 2022, the Oder River experienced an ecological disaster, resulting in the extinction of hundreds of aquatic organ- isms. Mass fsh deaths also occurred during that time in the Gliwice Canal, located in southern Poland, which connects to the upper section of the Oder River. The aim of the article was to assess the impact of the waters from the Gliwice Canal on the water quality changes in the Oder River, as expressed by chloride, sulphate, nitrate, phosphate content, as well as its parameters such as conductivity, temperature, and pH. Statistical analyses were conducted based on our own research and a series of data collected by the Chief Inspectorate for Environmental Protection. Below the confuence of the Oder River with the waters of the canal, an increase in sulphates levels and a decrease in sodium content were observed. The other parameters remained unchanged. It was also noted that the magnitude of each parameter was signifcantly higher in the waters of the Gliwice Canal compared to the Oder River. The research conclusion is that there is no infuence of the canals’ waters on the quality of the Oder River waters, both during the ecological disaster and afterwards. The presented research clearly indicates the need for separate analyses of fowing waters (with signifcantly higher salt and other pollutant dissolution capacity) and stagnant waters in water infrastructure (without water exchange).

  • Follow-up assessment of the microvascular function in patients with long COVID
    • Marzena Romanowska-Kocejko
    • Alicja Braczko
    • Agata Jędrzejewska
    • Marta Żarczyńska-Buchowiecka
    • Tomasz Kocejko
    • Barbara Kutryb-zając
    • Marcin Hellmann
    2025 MICROVASCULAR RESEARCH

    Long COVID is a complex pathophysiological condition. However, accumulating data suggests that COVID-19 is a systemic microvascular endothelial dysfunction with different clinical manifestations. In this study, a microvascular function was assessed in long COVID patients (n = 33) and healthy controls (n = 30) using flow-mediated skin fluorescence technique (FMSF), based on measurements of nicotinamide adenine dinucleotide fluorescence intensity during brachial artery occlusion (ischemic response, IR) and immediately after occlusion (hyperemic response, HR). Microcirculatory function readings were taken twice, 3 months apart. In addition, we quantified biochemical markers such as the serum L-arginine derivatives and hypoxia-inducible factor 1α (HIF1α) to assess their relation with microvascular parameters evaluated in vivo. In patients with long COVID, serum HIF1α was significantly correlated to IRindex (r = −0.375, p < 0.05). Similarly, there was a significant inverse correlation of serum asymmetric dimethyl-L-arginine levels to both HRmax (r = −0.343, p < 0.05) and HRindex (r = −0.335, p < 0.05). The IR parameters were found lower or negative in long COVID patients and recovered in three-month follow-up. Hypoxia sensitivity value was significantly higher in long COVID patients examined after three months of treatment based on the combination of ACE-inhibitors and beta-adrenolytic compared to baseline condition (85.2 ± 73.8 vs. 39.9 ± 51.7 respectively, p = 0.009). This study provides evidence that FMSF is a sensitive, non-invasive technique to track changes in microvascular function that was impaired in long COVID and recovered after 3 months, especially in patients receiving a cardioprotective therapy.

  • Forward-Based DC-DC Converter With Eliminated Leakage Inductance Problem
    • Oleksandr Matiushkin
    • Oleksandr Husev
    • Hossein Afshari
    • Enrique Romero-Cadaval
    • Carlos Roncero-Clemente
    2025 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

    The novel forward-based converter for low-power solar applications is presented in this work. The proposed converter provides an efficient performance in a wide range of the input voltage with low component count. The proposed dc-dc topologies are advanced forward dc-dc converters with an additional clamped output capacitor. The idea of such a type of converter is to transfer magnetizing energy of transformer to the output side, instead of using an input clamp circuit. Two possible topologies are considered to cover this feature. The design guidelines of the passive component of the proposed solutions are discussed. The converter may work in continuous conduction mode and discontinuous conduction mode due to different levels of the input power. A comparison between proposed topologies is made and discussed. Experimental prototype of the proposed forward-based dc-dc converter along with experimental results of the dc grid connection system are presented. The parameters of commercial photovoltaic panels have been chosen to validate the maximum power point tracking based on Perturb and Observe algorithm. The efficiency of the proposed solution is studied and discussed.

  • Framework for reliable and automatic multi-frequency correction of non-anechoic antenna measurements
    • Adrian Bekasiewicz
    • Mariusz Dzwonkowski
    • Vorya Waladi
    2025 MEASUREMENT

    Correction of antenna far-field measurements performed in uncontrolled environments is a challenging problem. Non-anechoic sites, while cheap compared to professional laboratories, suffer from poor propagation properties due to multipath interferences and noise from external sources of electromagnetic radiation. Direct measurements in such conditions are ineffective for drawing meaningful conclusions on antenna performance. The quality of obtained responses can be significantly enhanced through application of appropriate post-processing approaches. Unfortunately, performance of available techniques is subject to experience-based adjustment of algorithm-specific setup, often aided with rule-of-thumb solutions determined based on rudimentary experiments. In this work, limitations of existing manual, or semi-manual approaches to post-processing setup are showcased in contrast with an unsupervised tuning that employs rigorous numerical optimization. The proposed framework automates the determination of correction settings based on analysis of discrepancy between the refined antenna measurements against the responses obtained from electromagnetic simulations. It is the first deterministic, numerically-driven tool tailored for post-processing of data obtained in non-anechoic environments while eliminating the need for cognitive experimentation. A thorough evaluation of the method was performed in two test sites, incorporating five different setups and five correction techniques, for a total of 1250 experiments executed across 25 independent frequencies of interest and three antenna structures. Benchmark results that demonstrate usefulness of automatic setup adjustment when compared to rule-of-thumb methods are also provided.

  • Frequency Reconfigurable PIN Diode-Based Reuleaux-Triangle-Shaped Monopole Antenna for UWB/Ku Band Applications
    • Sena Esen Bayer Keskin
    • Sławomir Kozieł
    • Stanisław Szczepański
    2025 Pełny tekst Scientific Reports

    This paper presents a frequency reconfigurable monopole antenna developed for UWB/Ku band applications. The design employs a microstrip-fed Reuleaux-triangle-shaped patch with a defected ground structure. The antenna exhibits a wide operating bandwidth achieved due to rectangular slits integrated into the Reuleaux-triangle patch. Meanwhile, adding rectangular slots in the ground plane improves the return loss level. Frequency reconfigurability is obtained by utilizing PIN diodes to adjust the current distribution, altering the antenna's electrical length via the capacitive and inductive effects induced by the rings near the feed line. The antenna operates in two distinct frequency bands, 2.68-8.55 GHz and 12.7-15.65 GHz, contingent upon the PIN-diodes' ON/OFF states. In the OFF state, the antenna covers the UWB region, in particular, the ISM band (5.8 GHz), WLAN band (5.2 GHz), and lower X-band (8 GHz), exhibiting a 10 dB impedance bandwidth from 2.68 to 8.55 GHz with a maximum gain of 2.36 dBi. In the ON state, the antenna functions in the Ku band (12.7-15.65 GHz) with gains from 2.63 dBi to 3.85 dBi. The antenna's dynamic switching between UWB and Ku band operations makes it suitable for applications such as satellite communications, health monitoring, 5G, aerospace, and remote sensing.

  • Genetic Determinants and Biofilm Properties Useful in Estimation of UTI Pathogenicity of the Escherichia coli Strains Isolated from Free-Living Birds
    • Bartosz Rybak
    • Tomasz Jarzembowski
    • Agnieszka Daca
    • Beata Krawczyk
    • Lidia Piechowicz
    2025 Antibiotics-Basel

    Background/Objectives: According to the One Health concept, wild birds can be indicators of ecosystem pollution and disease incidence. Escherichia coli strains are widespread worldwide, but there are still few reports on the association of human infections with a potential reservoir of highly pathogenic human strains in wild birds. Fecal E. coli with uropathogenic potential (UPEC) can be transmitted between birds and humans and may be a risk factor for urinary tract infections (UTIs). Results: The results showed that above 50% of the isolates were grouped as highly pathogenic, according to Clermont phylogroup classification. Such strains were found to be stronger biofilm producers, with a higher adherence of monocytes than low pathogenic. However, the highest cytotoxicity was observed for strains described as aquatic environmental. Convergence of the results of the analysis of monocyte activation by E. coli strains and the ability to form biofilm by individual phylogroups of the strains tested was demonstrated. Genetic determinants of the uropathogenicity of E. coli (UPEC) correlate with the evidence of strain pathogenicity during monocyte activation in in vitro assays. Methods: In this study, we assessed the virulence potential of environmental strains isolated from wild waterfowl using genetic analysis (Clermont phylogroup classification) and phenotypic methods, including analysis of the human monocyte response to biofilm formation. The estimation of the ability to form biofilms was tested using crystal violet, and the pathogenic potential of strains by monocyte activation assay including changes in morphology, adhesion and cytotoxicity. Conclusions: In conclusion, the virulence of E. coli strains isolated from free-living birds is significant, and they can be considered environmental reservoirs of pathogenic strains. According to our observations, they can be responsible for the dissemination of uropathogenic strains among humans.

  • Gold(III) complexes with chloride and cyanopyridines: Facilitated hydrolysis of nitrile ligand to amide and antibacterial activity
    • Maciej Ejnik
    • Piotr Bruździak
    • Karolina Gutmańska
    • Anna Ciborska
    • Magdalena Malik
    • Dietrich Gudat
    • Anna Brillowska-Dąbrowska
    • Anna Dołęga
    2025 SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY

    A range of novel simple gold(III) compounds has been synthesized in their monocrystalline form, including two previously unknown chloro-complexes of Au3+ with 2-cyanopyridine or 3-cyanopyridine, respectively. Our investigations have revealed the intricate nature of the reaction between 2-cyanopyridine and tetrachloroauric acid, yielding at least three distinct products. The main product, obtained in high yield, is a salt featuring a tetrachloroauric anion and a pyridinium cation stabilized by a hydrogen bond to a further 2-cyanopyridine molecule. Moreover, we observed the in-situ formation of a 2-cyanopyridine-AuCl3 complex, which undergoes hydrolysis of the nitrile bond to yield a picolinamide-Au(III) complex. The complexes were characterized by IR and Raman spectroscopies, NMR spectroscopy, and single-crystal XRD studies. Additional computational studies were conducted to explain unusual spectral features, the observed disparities in the complexation reactions of the three isomeric cyanopyridine ligands and the distinct reactivity of the complex with 2-cyanopyridine. Based on these studies, we propose a mechanism for the catalyzed hydrolysis of the nitrile bond within the Au(III) complex. Finally, we assessed the antimicrobial efficacy of the synthesized gold(III) complexes against a spectrum of bacteria and fungi.

  • Grey wolf optimizer integrated within boosting algorithm: Application in mechanical properties prediction of ultra high-performance concrete including carbon nanotubes
    • A. Ӧzyüksel Çiftçioğlu
    • Farzin Kazemi
    • Torkan Shafighfard
    2025 Applied Materials Today

    Nowadays, the construction industry has increasingly recognized the superior performance characteristics of ultra high-performance concrete (UHPC). Known for its exceptional durability and high tensile strength, UHPC material is revolutionizing structure standards subjected to extreme environmental conditions and heavy loads. This paper explores the enhancement of UHPC with nano- and micromaterials, employing advanced machine-learning (ML) techniques to optimize the prediction of mechanical properties. Moreover, by introducing the novel extreme gradient boosting (XGBoost) improved by grey wolf optimizer (GWO) algorithm, this research represents the first integration of ML with GWO in UHPC research, significantly enhancing the accuracy of predictions for key properties such as compressive, tensile, and flexural strengths. The study investigates the impact of nanotechnology on UHPC, specifically how carbon nanotubes (CNTs) and microscale reinforcements contribute to advances in strength, durability, and resilience. These enhancements are pivotal in addressing limitations of traditional concrete, especially in high-demand construction environments. The proposed GWO-XGB model has demonstrated a remarkable ability to achieve R2 values of 98.4% and 94.8% for UHPC with nanomaterial and micromaterial, respectively, indicating very high level of accuracy in predicting mechanical properties. This model also had one of the lowest error values, demonstrating its precision and ability to minimize prediction errors. This approach significantly facilitates the testing and development of UHPC by automating the accurate determination of its mechanical properties, thereby reducing the reliance on costly and time-consuming experimental methods. Highlighting the transformative potential of combining ML with engineering science, this study offers promising avenues for innovations in construction practices.

  • Gromologist: A GROMACS-oriented utility library for structure and topology manipulation
    • Miłosz Wieczór
    • Jacek Czub
    • Modesto Orozco
    2025 SoftwareX

    Despite the increasing automation of workflows for the preparation of systems for molecular dynamics simulations, the custom editing of molecular topologies to accommodate non-standard modifications remains a daunting task even for experienced users. To alleviate this issue, we created Gromologist, a utility library that provides the simulation community with a toolbox of primitive operations, as well as useful repetitive procedures identified during years of research. The library has been developed in response to users’ feedback, and will continue to grow to include more use cases, thorough automatic testing and support for a broader spectrum of rare features. The program is available at gitlab.com/KomBioMol/gromologist and via Python’s pip.

  • Guided ultrasonic wave technique for corrosion monitoring and thickness variability analysis
    • Beata Zima
    2025 MEASUREMENT

    Corrosion degradation poses a significant challenge to the structural integrity of industrial components, especially in critical sectors such as oil and gas, marine, and energy. This paper presents a novel approach to assessing corrosion damage using guided ultrasonic waves (GUWs), focusing on the statistical characterization of thickness variability in corroded plates. A combined algorithm is developed to estimate key statistical parameters, such as mean thickness and standard deviation, which describe the geometry of plates affected by corrosion. The study integrates theoretical analysis, experimental tests, and numerical simulations using Abaqus/Explicit to model plates with irregular thickness, employing random field methods to simulate surface roughness caused by corrosion. Experimental validation was conducted on steel plates subjected to accelerated corrosion tests, and guided waves were used to evaluate thickness variations along different propagation paths. The results demonstrate the accuracy of the proposed method in estimating the key geometrical parameters of corroded plates, even in the presence of complex surface degradation. This approach offers a significant improvement in the non-destructive testing of structural elements and can be an alternative to standard ultrasonic gauge measurement.

  • Harnessing low-cost LiDAR scanners for deformation assessment of 3D-printed concrete-plastic columns with cross-sections based on fractals after critical compressive loading
    • Piotr Kędziorski
    • Aneta Skoratko
    • Jacek Katzer
    • Paweł Tysiąc
    • Marcin Jagoda
    • Machi Zawidzki
    2025 MEASUREMENT

    This article aims to explore the potential of using low-cost devices (iPhone and iPad) equipped with LiDAR scanners in the context of measuring the volume of concrete-plastic specimens with complex shapes. The goal was to assess whether these tools can support or even replace traditional metrology methods. For the purpose of the research program concrete-plastic columns with very complex cross-sections (based on different fractals) were harnessed. The research team was focused on analyzing the potential of using this technology to measure the volume of concrete-plastic structural elements created with the help of 3D printing. The tests were conducted under laboratory conditions. The effectiveness of the proposed approach was compared with results obtained using photogrammetry. The challenges of measurement accuracy, the impact of specimen shape, the impact of material and needed optimization of post-processing on the achieved results were also discussed.

  • High Internal Phase Oil-in-Water Emulsions Stabilised by Cost-Effective Rhamnolipid/Alginate Biocomplexes
    • Ilona Kłosowska-Chomiczewska
    • Gabriela Burakowska
    • Paulina Żmuda-Trzebiatowska
    • Aleksandra Soukup
    • Iwona Rok-Czapiewska
    • Elżbieta Hallmann
    • Tetiana Pokynbroda
    • Olena Karpenko
    • Krystyna Mędrzycka
    • Adam Macierzanka
    2025 Pełny tekst MOLECULES

    A novel, cost-effective, partially purified biosurfactant in the form of a rhamnolipid biocomplex (RLBC) was investigated for its emulsifying properties. The RLBC was obtained through the cultivation of Pseudomonas sp. SP-17 on glycerol, followed by acidic precipitation, without the use of organic solvents for isolation or purification. Composed of rhamnolipids (RLs) and the exopolysaccharide alginate, RLBC exhibited emulsifying properties towards rapeseed oil comparable to those of purified RLs at concentrations as low as 0.15% (w/w), sufficient for the effective stabilisation of oil-in-water (o/w) high internal phase emulsions (HIPEs, 80% oil). Dynamic light scattering analysis revealed similar droplet sizes (9.54 ± 0.96 µm for RLBC vs. 8.93 ± 0.58 µm for RLs), while multiple light scattering confirmed high emulsion stability over 120 days. The emulsions displayed shear-thinning behaviour, with yield stresses of approximately 11.5 Pa and 7.7 Pa for systems prepared with RLBC and RLs, respectively, after seven days of pre-storage. Although increasing the RLBC concentration from 0.15% to 1% (w/w) slightly improved the degree of emulsion dispersion, it did not substantially impact the long-term stability observed at the lowest concentration. Biodegradation tests demonstrated that the RLBC preparations are environmentally friendly alternatives to synthetic surfactants, achieving 60% biodegradation within 2.5 days and complete biodegradation within 14 days, which outperformed synthetic emulsifiers. The RLBC offers both environmental and economic advantages over purified RLs, including reduced production costs and the elimination of organic solvents. Our findings highlight the potential of RLBC for stabilising HIPEs in applications requiring sustainable and biodegradable formulations, such as cosmetics, lubricants, and industrial fluids widely manufactured and utilised today.

  • High performance ozone nanobubbles based advanced oxidation processes (AOPs) for degradation of organic pollutants under high pollutant loading
    • Priya Koundle
    • Neelkanth Nirmalkar
    • Grzegorz Boczkaj
    2025 JOURNAL OF ENVIRONMENTAL MANAGEMENT

    Advanced Oxidation Processes (AOPs) have proven to be an effective solution for chemical wastewater treatment, particularly for degradation of organic pollutants, especially dyes. Ozonation is recognized as one of the most prevalent AOPs. Nevertheless, some cases show a lowered efficiency of O3 utilization which is attributed to its inadequate distribution in the treated water causing low residence time, low mass transfer coefficient as well as shorter half-life. This study demonstrates the application of ozone nanobubbles to enhance the degradation of organics under high pollution load conditions. We propose an integrated method that utilizes bulk nanobubbles to enhance the reactivity of ozone for the degradation of organics. We examined the degradation of organic pollutants under parameters such as varying pH levels, ozone concentrations and presence of salts and surfactants. The degradation of the organic pollutant by ozone nanobubbles (0.177 L mg−1min−1) demonstrated a threefold increase in reaction rate constants compared to microbubbles (0.025 L mg−1min−1). The plausible reason for these findings is (i) higher mass transfer coefficient (ii) higher ozone solubility (iii) NBs may act as a surface for chemical reaction (iv) NBs may increase the half-life of ozone. The presence of reactive oxygen species was verified using scavenging tests. This part of the studies revealed contribution of reactive oxygen species (ROSs) such as hydroxyl radical (•OH), superoxide radical anion (O2•-) and singlet oxygen (1O2) in the degradation process. The conditions that provide total degradation of 100% in 300 s for both organic pollutants (Green rit and methylene blue dye) are: 5 LPM (Litre per minute) ozone flow rate, acidic pH, monovalent salts (NaCl, 2 mM) and lower concentration of surfactants (CTAB and SDS, 0.3 CMC). A degradation mechanism has been outlined based on intermediates identified by LC-MS. This work presents a new method that combines AOPs with nanobubbles, which should lead to increased environmental sustainability and efficiency.