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  • Emission and properties of airborne wear particles from train brake friction materials based on novolac phenolic resins and butadiene rubbers
    • Yurii Tsybrii
    • Oleksii Nosko
    • Izabela Zglobicka
    • Michal Kuciej
    2024 WEAR

    The emission of airborne particulate matter from a train brake depends on the formulation of its friction material. This study investigates the emission and properties of wear particles from train brake friction materials based on straight or resorcinol-modified novolac phenolic resin and nitrile or styrene butadiene rubber used as binding ingredients. The wear particles are generated by a pin-on-disc tribomachine inside an aerodynamic chamber, counted and collected using aerosol measurement techniques, subjected to microscopic and elemental analysis. It has been found that the modification of novolac phenolic resin with resorcinol has no considerable effects on the emission of wear particles and their properties. By contrast, replacing styrene butadiene rubber with nitrile butadiene rubber leads to a significant decrease in the emission of 0.1–10 μm wear particles.

  • Employment of University Graduates in the Era of Digitalization and Artificial Intelligence: Challenges and Prospects
    • Nina Rizun
    • Halina Ryzhkova
    • Irena Pawłyszyn
    • Charalampos Harris Alexopoulos
    2024

    Digital technologies are profoundly reshaping the labor market, causing structural shifts in the economy and altering the nature of work. These changes have significant implications for youth employment, exacerbating the issue of unemployment. This paper delves into the importance of graduate employment in contemporary society, with a particular focus on the influence of digital technologies and Artificial Intelligence. The authors explore the challenges associated with digital transformation and underscore the pivotal role of universities in nurturing skills essential for successful employment. The paper also looks at the prospects for graduates in this dynamic environment, which offers both challenges and opportunities for career growth. This research may be relevant for developing directions to improve the preparation of students for the rapidly changing labor market

  • Emulsifying blends based on natural fats for eco-design of O/W emulsions
    • Patrycja Szumała
    • Elżbieta Pyrz
    2024 JOURNAL OF CLEANER PRODUCTION

    Emulsifier blends are most often used to stabilize and modulate the properties of cosmetic and pharmaceutical emulsions, such as skin care or application-related consistency. However, the rational design of such emulsifier blends is often not well understood, especially when their ingredients are natural raw materials. This study aimed to analyze the influence of natural fatty ingredients selected as emulsifiers on the emulsion properties. For this purpose, the stability, microstructure and rheological properties of the produced emulsions were monitored during their storage. The effect of five blends containing fatty alcohols, cetyl palmitate, beeswax, avocado butter and one typical emulsifier, i.e. sorbitan oleate, in various weight proportions, was analyzed. Even though the blends contained only hydrophobic ingredients, O/W type emulsions were obtained. The results indicate that all blends can stabilize O/W emulsions, but with a specific qualitative and quantitative composition. The crystal structures created by the blend components were responsible for the stabilization of all emulsions, but the most beneficial properties were provided by the blend with the addition of beeswax and sorbitan oleate. These findings provide new insights into the design of safe and ecological emulsions.

  • Encapsulation of Cs3Bi2Br9 perovskite photocatalyst with polythiophene for prolonged activity in oxidizing and humid environment
    • Magdalena Miodyńska
    • Olga Kaczmarczyk
    • Wojciech Lisowski
    • Andrzej Żak
    • Tomasz Klimczuk
    • Monika Paszkiewicz
    • Adriana Zaleska-Medynska
    2024 Pełny tekst APPLIED SURFACE SCIENCE

    Despite their growing popularity in modern technology, halide perovskites suffer from susceptibility to oxidation, limiting their applications. Our aim was to enhance Cs3Bi2Br9 perovskite's performance in humid environments through polythiophene encapsulation. This extended its lifespan while preserving photocatalytic abilities, as demonstrated in toluene decomposition experiments. We confirmed the stability of Cs3Bi2Br9 encapsulated with polythiophene over four photocatalytic cycles and identified photogenerated electrons and superoxide radicals as key contributors to toluene decomposition. Benzaldehyde was detected as the primary toluene decomposition product, and we observed partial pollutant mineralization, evidenced by increased CO2 concentration after photocatalysis. Additionally, using hybrid ex–situ transmission electron microscopy, we observed delayed oxidation of encapsulated perovskite. Encapsulation hindered, but did not entirely prevent, water vapor penetration into Cs3Bi2Br9 particles. This progress suggests promising prospects for perovskite–based composites retaining photocatalytic capabilities under elevated humidity conditions.

  • Energy-Efficient Self-Supervised Technique to Identify Abnormal User Over 5G Network for E-Commerce
    • Arsalan Muhammad Soomar
    2024 IEEE TRANSACTIONS ON CONSUMER ELECTRONICS

    Within the realm of e-commerce networks, it is frequently observed that certain users exhibit behavior patterns that differ substantially from the normative behaviors exhibited by the majority of users. The identification of these atypical individuals and the understanding of their behavioral patterns are of significant practical significance in maintaining order on e-commerce platforms. One such method for accomplishing this objective entails examining the behavioral tendencies of atypical users through the abstraction of e-commerce networks as heterogeneous information networks. These networks are then transformed into a bipartite graph that establishes associations between users and devices. The Self-Supervised Aberrant Detection Model (SAD) has been proposed within this theoretical framework as a means to identify and detect users who exhibit aberrant behavior. The SSADM methodology utilizes a self-supervised learning process that utilizes autoencoders to encode representations of user nodes. The proposed method aims to maximize a combined objective function for backpropagation while utilizing support vector data description to detect abnormalities in the representations of user nodes. In summary, many tests have been conducted utilizing both authentic network datasets and partially synthetic network datasets to demonstrate the efficacy and superiority of the SAD technique, specifically within the domain of an energy-efficient 5G network.

  • Engineering education for smart grid systems in the quasi-industrial environment of the LINTE^2 laboratory
    • Andrzej Augusiak
    • Filip Kutt
    • Piotr Musznicki
    • Janusz Nieznański
    2024 Global Journal of Engineering Education

    Smart grid systems are revolutionising the electric power sector, integrating advanced technologies to enhance efficiency, reliability and sustainability. It is important for higher education to equip the prospective smart grid professional with the competencies enabling them to navigate through the related complexities and drive innovation. To achieve this, interdisciplinary education programmes are necessary, addressing inter alia integration of renewable energy sources, data analytics, AI and machine learning, cybersecurity, policies and regulatory frameworks. Hands-on experience, industrial training and research-based learning are also highly desirable components of such programmes. This article describes how Gdańsk University of Technology (Gdańsk Tech), Gdańsk, Poland, employs its unique Laboratory for Innovative Power Systems and Integration of Renewable Energy Sources (LINTE^2 Lab), to support comprehensive education in smart grids. Starting with simulation and virtualisation, students gradually extend their knowledge and competencies through project, research and challenge-based activities in the quasi-industrial environment of the LINTE^2 Lab.

  • Enhanced acceptor concentration, proton conductivity, and hydration in multicomponent rare‐earth ortho‐niobates
    • Arkadiusz Dawczak
    • Wojciech Skubida
    • Aleksandra Mielewczyk-Gryń
    • Maria Gazda
    2024 JOURNAL OF THE AMERICAN CERAMIC SOCIETY

    The structural properties of (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series have been studied by X-ray powder diffraction at room temperature. The thermal properties were investigated using thermogravimetry, from which the concentration of proton defects was determined. Additionally, dilatometry studies were carried out, from which the thermal expansion coefficients and the phase transition temperature between low- and high-temperature polymorphs were determined. In order to determine the electrical properties, the electrochemical impedance spectroscopy measurements under atmospheres of dry synthetic air and saturated with water vapor and heavy water at 300–800°C temperature range were performed. All the studied materials were single-phase compositions and were stable in monoclinic I2/c crystal structure at room temperature. The water uptake studies revealed a small mass change under the switch from dry to humidified synthetic air atmospheres, suggesting the formation of proton defects. The phase transition from monoclinic to tetragonal crystal structure in the (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series occurs above 650°C. A small amount of calcium dopant increases the total conductivity in all tested atmospheres by two orders of magnitude, for example, from 0.34 μS cm−1 in La0.2Nd0.2Sm0.2Gd0.2Eu0.2NbO4 to 63.7 μS cm−1 in (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)0.95Ca0.05NbO4−δ at 700°C in humid synthetic air atmosphere.

  • Enhanced cellulose extraction from agave plant (Agave americana Species) for synthesis of magnetic/cellulose nanocomposite for defluoridation of water
    • Samuel Latebo Majamo
    • Temesgen Amibo
    • Ermias Tsegaw
    2024 Materials Today Communications

    Research on fluoride removal from water is currently focusing on the development of innovative materials for defluoridation water. The current study extracted and used enhanced cellulose from Agave americana species to synthesize a magnetic/cellulose nanocomposite for water defluoridation. Strong and light binary acids (H2SO4 and CH3COOH) were utilized to pretreat raw material to enhance cellulose extraction. Central composite design (CCD) was used to design experiments to find optimum condition for cellulose extraction. Four key factors (H2SO4 to CH3COOH ratio, acid concentration, temperature, and contact time) with three levels were designed by CCD. The lignin, hemicellulose and cellulose content of raw agave cellulosic fiber in this study were 5.5 ± 0.27, 20.5 ± 0.23 and 60.4 ± 0.31 % respectively. While, at the optimum conditions of 2.3 % acid concentration, 0.44 H2SO4 to CH3COOH ratio, 83.2 min of retention time, and 105.5 oC, cellulose content reached 940.25 %. Then, enhanced cellulose was covered with magnetic components, resulting in a magnetic/cellulose nano- composite. The adsorbent materials were characterized by Fourier Transform Infrared (FTIR) spectroscopy, X- Ray Diffractometer (XRD), Scanning electron microscopy (SEM), and Dynamic light scattering (DLS). In addition, textural features of the adsorbent were investigated. All characterization results suggest that the synthesized adsorbent has the required properties. Adsorption tests were carried out using various interaction components. The combined effects of critical process variables on defluoridation were examined. The adsorption isotherm was calculated. Overall, the research demonstrated that the produced magnetic/cellulose nanocomposite can be employed as an efficient and ecologically acceptable adsorbent for fluoride removal from water.

  • Enhanced electrochemical activity of boron-doped nanocarbon functionalized reticulated vitreous carbon structures for water treatment applications
    • Iwona Kaczmarzyk
    • Mariusz Banasiak
    • Paweł Jakóbczyk
    • Michał Sobaszek
    • Gabriel Strugała
    • Tomasz Seramak
    • Paweł Rostkowski
    • Jakub Karczewski
    • Mirosław Sawczak
    • Jacek Ryl
    • Robert Bogdanowicz
    2024 Pełny tekst DIAMOND AND RELATED MATERIALS

    An extraordinary charge transfer kinetics and chemical stability make a boron-doped diamond (BDD) a prom- ising material for electrochemical applications including wastewater treatment. Yet, with flat geometrical sur- faces its scaling options are limited. In this study, the reticulated Vitreous Carbon (RVC) served as a substrate for boron-doped diamondized nanocarbons (BDNC) film growth resulting with complex heterogeneity carbon structures with different morphologies defined by using electron microscopy, microtomography, activation en- ergy studies, and Raman spectroscopy. The proposed modification significantly boosted the electrochemical Fe(CN)6 3 /4 redox activity. The vol- tammetry and impedimetric studies revealed its origin as a significantly higher share of electrochemically active sites at the BDNC@RVC electrode (increased by 114 %) combined with enhanced heterogeneous rate constant (2× increase up to 8.24⋅10 4 cm s 1). Finally, to establish its applicability for water treatment, the BDNC@RVC was studied as the anode in electrochemical paracetamol decomposition. Boron-enriched nanoarchitecture formed at the RVC electrode surface substantially reduced the oxidation energy barrier manifested as a decrease in activation overpotential by 212 mV, which gave a consequence in a 78 % removal rate (in 4 h, at 0.7 mA cm 2), 12 % higher than bare RVC and yielding lower amounts of APAP decomposition intermediates.

  • Enhanced Electrochemical Performance of MnCo1.5Fe0.5O4Spinel for Oxygen Evolution Reaction through Heat Treatment
    • Krystian Lankauf
    • Bartłomiej Lemieszek
    • Karolina Górnicka
    • Patryk Błaszczak
    • Marcin Zając
    • Piotr Jasiński
    • Sebastian Molin
    2024 Pełny tekst ENERGY & FUELS

    MnCo1.5Fe0.5O4 spinel oxide was synthesized using the sol−gel technique, followed by heat treatment at various temperatures (400, 600, 800, and 1000 °C). The prepared materials were examined as anode electrocatalysts for watersplitting systems in alkaline environments. Solid-state characterization methods, such as powder X-ray diffraction and X-ray absorption spectroscopy (XAS), were used to analyze the materials’ crystallographic structure and surface characteristics. The intrinsic activity of the MnCo1.5Fe0.5O4 was fine-tuned by altering the electronic structure by controlling the calcination temperature, and the highest activity was observed for the sample treated at 800 °C. A shift in the valence state of surface cations under oxidative conditions in an alkaline solution during the oxygen evolution reaction was detected through ex situ XAS measurements. Moreover, the influence of the experimental conditions on the electrocatalytic performance of the material, including the pH of the electrolyte and the temperature, was demonstrated.

  • Enhanced electrochemical performance of partially amorphous La0.6Sr0.4CoO3-δ oxygen electrode materials for low-temperature solid oxide cells operating at 400 °C
    • Bartłomiej Lemieszek
    • Mindaugas Ilickas
    • Jan Jamroz
    • Asta Tamulevičienė
    • Jakub Karczewski
    • Patryk Błaszczak
    • Alexey Maximenko
    • Brigita Abakevičiene
    • Marcin Małys
    • Sigitas Tamulevičius
    • Piotr Jasiński
    • Sebastian Molin
    2024 Pełny tekst APPLIED SURFACE SCIENCE

    This work evaluates partially amorphous La0.6Sr0.4CoO3-δ (LSC) as a potential oxygen electrode for lowtemperature solid oxide cells. LSC was deposited using the spin-coating technique onto Ce0.8Gd0.2O2-δ (CGO) substrates. The optimal oxygen electrode thickness was determined as 500 nm. The electrochemical impedance spectroscopy (EIS) study showed a significant improvement in oxygen reduction/oxidation reaction kinetics when annealing temperatures below 600 ◦C. The lowest value of the polarisation resistance was observed for the sample annealed at 400 ◦C, followed by a temperature of 500 ◦C. EIS measurements at different pO2 content were performed at levels between 0.5 % and 20 %. A comprehensive equivalent circuit analysis was carried out for an explanation of the limiting factors of the catalytic reaction. X-ray absorption fine structure analysis allowed for the identification of differences between crystalline LSC and its partially amorphous form. X-ray absorption nearedge spectroscopy analysis indicated that cobalt adopts a lower oxidation state for the partially amorphous form. Moreover, extended X-ray absorption fine structure analysis indicated the decreased of cobalt oxidation state in partially amorphous LSC. It can be assumed that the increased activity of LSC at temperatures below the crystallization may be due to increased defects and oxygen vacancies in the material.

  • Enhanced Mechanical and Electromechanical Properties of Compositionally Complex Zirconia Zr1–x(Gd1/5Pr1/5Nd1/5Sm1/5Y1/5)xO2−δ Ceramics
    • Ahsanul Kabir
    • Bartłomiej Lemieszek
    • Maxim Varenik
    • Victor Buratto Tinti
    • Sebastian Molin
    • Igor Lubomirsky
    • Vincenzo Esposito
    • Frank Kern
    2024 ACS Applied Materials & Interfaces

    Compositionally complex oxides (CCOs) or high-entropy oxides (HEOs) are new multi-element oxides with unexplored physical and functional properties. In this work, we report fluorite structure derived compositionally complex zirconia with composition Zr1- x(Gd1/5Pr1/5Nd1/5Sm1/5Y1/5)xO2-δ (x = 0.1 and 0.2) synthesized in solid-state reaction route and sintered via hot pressing at 1350 °C. We explore the evolution of these oxides' structural, microstructural, mechanical, electrical, and electromechanical properties regarding phase separation and sintering mechanisms. Highly dense ceramics are achieved by bimodal mass diffusion, composing nanometric tetragonal and micrometric cubic grains microstructure. The material exhibits an anomalously large electrostriction response exceeding the M33 value of 10−17 m 2 /V2 at room temperatures and viscoelastic properties of primary creep in nanoindentation measurement under fast loading. These findings are strikingly similar to those reported for doped ceria and bismuth oxide derivates, highlighting the presence of a large concentration of point defects linked to structural distortion and anelastic behavior are characteristics of nonclassical ionic electrostrictors.

  • Enhanced Spectroscopic Insight into Acceptor-Modified Barium Strontium Titanate Thin Films Deposited via the Sol–Gel Method
    • Dionizy Czekaj
    • Agata Lisińska-Czekaj
    2024 Pełny tekst Materials

    In the present paper, composite thin films of barium strontium titanate (BaxSr1−xTiO3) with an acceptor modifier (magnesium oxide—MgO) were deposited on metal substrates (stainless steel type) using the sol–gel method. The composite thin films feature BaxSr1−xTiO3 ferroelectric solid solution as the matrix and MgO linear dielectric as the reinforcement, with MgO concentrations ranging from 1 to 5 mol%. Following thermal treatment at 650 °C, the films were analyzed for their impedance response. Experimental impedance spectra were modeled using the Kohlrausch–Williams–Watts function, revealing stretching parameters (β) in the range of approximately 0.78 to 0.89 and 0.56 to 0.90 for impedance and electric modulus formalisms, respectively. Notably, films modified with 3 mol% MgO exhibited the least stretched relaxation function. Employing the electric equivalent circuit method for data analysis, the “circle fit” analysis demonstrated an increase in capacitance from 2.97 × 10−12 F to 5.78 × 10−10 F with the incorporation of 3 mol% MgO into BST-based thin films. Further analysis based on Voigt, Maxwell, and ladder circuits revealed trends in resistance and capacitance components with varying MgO contents, suggesting non-Debye-type relaxation phenomena across all tested samples.

  • Enhanced visible light-activated gas sensing properties of nanoporous copper oxide thin films
    • Andrzej Kwiatkowski
    • Janusz Smulko
    • Katarzyna Drozdowska
    2024 Pełny tekst SOLAR ENERGY MATERIALS AND SOLAR CELLS

    Metal oxide gas sensors are popular chemoresistive sensors. They are used for numerous tasks, including environmental and safety monitoring. Some gas-sensing materials exhibit photo-induced properties that can be utilized for enhanced gas detection by modifying the sensor selectivity and sensitivity when illuminated by light. Here, we present the gas sensing characteristics of highly nanoporous Cu2O thin films towards both electrophilic (NO2) and nucleophilic (C2H5OH, NH3) gas molecules under ambient temperature and modulated by visible light illumination of different colors (red: 632 nm, green: 530 nm, blue: 468 nm). Cu2O films were fabricated by reactive advanced gas deposition (AGD) technology. The surface and structural analysis of the samples confirm the deposition of nanoporous thin films of mixed copper oxide phases. The gas sensing property of Cu2O exhibited expected p-type semiconductor behavior upon electrophilic and nucleophilic gas exposures. Our results show that visible light illumination provides enhanced sensor response.

  • Enhancing chain-elongating microbiomes: Sequential fungi-bacteria cooperation for efficient food waste upgrading using endogenous electron donors
    • Xiang Li
    • Xiaolin Lei
    • Zhichao Guo
    • Ziyi Yan
    • Xia Gu
    • Xianbao Xu
    • Hussein Al-Hazmi
    • Gang Xue
    • Jiajie Xu
    • Piotr Oleskowicz-Popiel
    • Jacek Mąkinia
    2024 CHEMICAL ENGINEERING JOURNAL

    The upgrading of organic waste such as food waste (FW) into medium-chain carboxylates (MCC) is within a bio-based circular economy concept. An efficient chain elongation (CE) microbiome is difficult to obtain, which normally requires long-term acclimatization and an exogenous supplement of electron donor (ED, especially ethanol). In this study, the CE microbiome was rapidly shaped within 18 days and an efficient endogenous ethanol-based CE was achieved through the amendment of distiller yeast (DY) during FW fermentation. Multiple FW feeding accumulated the caproate concentration to 5.76 ± 0.33 g COD/L, which also regulated the CE process from ethanol-dependent to lactate-dependent metabolism. During the lactate-based CE process, the caproate production increased linearly (R2 = 0.82) with the rising D-lactate content. Ethanol-producing fungi yeast mainly consisted of Wickerhamomyces (66.54 %), Saccharomycopsis (5.37 %), Issatchenkia (2.21 %), unclassified_f_Metschnikowiaceae (1.73 %), and Saccharomyces (1.33 %). These yeasts were eliminated by FW feeding, which was in line with the alteration of ED preference from ethanol to lactate. Metagenome analysis indicated that the total relative abundance of lactate-based chain elongators including Ruminococcaceae bacterium CPB6, Clostridium luticellarii, Caproiciproducens galactitolivorans, and Megasphaera elsdenii was increased by 28.6 %, while the ethanol-based chain elongator Clostridium kluyveri kept stable after FW feeding. In addition, the functional genes related to the oxidation of lactate to acetyl-CoA were enriched after FW feeding, which further enhanced the subsequent CE pathway of acetyl-CoA-based reverse β oxidation rather than the fatty acids synthesis. This study provides a new insight into upgrading FW into valuable MCC without exogenous ED addition.

  • Enhancing colloidal stability of nanodiamond via surface modification with dendritic molecules for optical sensing in physiological environments
    • Maciej Głowacki
    • Paweł Niedziałkowski
    • Jacek Ryl
    • Marta Prześniak-Welenc
    • Mirosław Sawczak
    • Klaudia Prusik
    • Mateusz Ficek
    • Monika Janik
    • Krzysztof Pyrchla
    • Michał Olewniczak
    • Krzysztof Bojarski
    • Jacek Czub
    • Robert Bogdanowicz
    2024 Pełny tekst JOURNAL OF COLLOID AND INTERFACE SCIENCE

    Pre-treatment of diamond surface in low-temperature plasma for oxygenation and in acids for carboxylation was hypothesized to promote the branching density of the hyperbranched glycidol polymer. This was expected to increase the homogeneity of the branching level and suppress interactions with proteins. As a result, composite nanodiamonds with reduced hydrodynamic diameters that are maintained in physiological environments were anticipated. Surfaces of 140-nm-sized nanodiamonds were functionalized with oxygen and carboxyl groups for grafting of hyperbranched dendritic polyglycerol via anionic ring-opening polymerization of glycidol. The modification was verified with Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy. Dynamic light scattering investigated colloidal stability in pH-diverse (2–12) solutions, concentrated phosphate-buffered saline, and cell culture media. Thermogravimetric analysis of nanodiamonds-protein incubations examined non-specific binding. Fluorescence emission was tested across pH conditions. Molecular dynamics simulations modeled interparticle interactions in ionic solutions. The hyperbranched polyglycerol grafting increased colloidal stability of nanodiamonds across diverse pH, high ionic media like 10 × concentrated phosphate-buffered saline, and physiological media like serum and cell culture medium. The hyperbranched polyglycerol suppressed non-specific protein adsorption while maintaining intensive fluorescence of nanodiamonds regardless of pH. Molecular modelling indicated reduced interparticle interactions in ionic solutions correlating with the improved colloidal stability.

  • Enhancing electrical properties through in-situ controlled nanocrystallization of V2O5–TeO2 glass
    • Piotr Okoczuk
    • Agnieszka Kwiatkowska
    • Leon Murawski
    • Tomasz Pietrzak
    • Natalia Wójcik
    • Fabian Garmroudi
    • Leszek Wicikowski
    • Barbara Kościelska
    2024 Pełny tekst JOURNAL OF MATERIALS SCIENCE

    V2O5–TeO2 glass–ceramics (VTGC) were prepared by controlled annealing of the V2O5–TeO2 glass (VTG), which illustrates a parent glass matrix with a single charge carrier. The annealing proceeded at six temperatures selected between the glass transition and the maximum of the frst crystallization process to obtain various nanocrystallite sizes. Heat treatment caused an increase in DC conductivity by 2.5–3.5 (250–285 °C) order of magnitude. Using thermal analysis, the crystal growth process was determined to be 1D. Structural studies show that the obtained materials are partially amorphous and polycrystalline with nanometersized crystallites. Subtle thread-like structures were observed using conductive AFM. The activation energy of the conduction process decreased from 0.38 eV in VTG to 0.18–0.11 eV (250–285 °C) in VTGC. The radii of crystallites were calculated based on the theoretical model of electron hopping between connected semiconducting nanocrystallites and vary between 1.7 and 2.8 nm (250–285 °C). Thermoelectric studies indicate constant carrier concentration. Features characteristic of small polaron hopping-governed materials were observed. We suggest V3O7 nanocrystals as conductive media in VTGC.

  • Enhancing environmental literacy through urban technology-based learning. The PULA app case
    • Ewa Duda
    • Helena Anacka
    • Hanna Obracht-prondzyńska
    • Hanne Cecilie Geirbo
    • Jolanta Kowal
    2024

    This study addresses the need to enhance environmental literacy, focusing on urban adults through mobile applications, based on the example of PULA app that engages early adopters in gamified pro- environmental activities, offering insights into informal learning. Grounded in 'urban pedagogy,' the study combines semi-structured interviews with 17 application testers and quantitative data analysis, unveiling motivations, user feedback, and success aspects. Motivations include a desire for environmental impact, heightened climate awareness, and behavioral transformation. Users perceive knowledge increase as a key benefit, emphasizing educational features, gamification, and social interaction. Success aspects manifest in a sense of belonging, positive behavioral changes, and heightened environmental responsibility. Optimizing the environmentally-friendly app requires continuous gamified content innovation, technical issue resolution, and diverse educational content. Strengthening social interaction features and conducting longitudinal studies are crucial for sustained impact. This study advances our understanding of mobile apps' role in promoting environmental literacy, emphasizing the transformative potential of digital platforms and collaborative efforts for sustainable impact.

  • Enhancing nitrogen removal in the partial denitrification/anammox processes for SO4− - Rich wastewater treatment: Insights into autotrophic and mixotrophic strategies
    • Dominika Derwis
    • Hussein Al-Hazmi
    • Joanna Majtacz
    • Slawomir Ciesielski
    • Jacek Mąkinia
    2024 Pełny tekst JOURNAL OF ENVIRONMENTAL MANAGEMENT

    The investigation of partial denitrification/anammox (PD/anammox) processes was conducted under autotrophic (N–S cycle) and mixotrophic (N–S–C cycle) conditions over 180 days. Key findings revealed the remarkable capability of SO42--dependent systems to produce NO2− effectively, supporting anaerobic NH4+ oxidation. Additionally, SO42− served as an additional electron acceptor in sulfate reduction ammonium oxidation (SRAO). Increasing influent SO42− concentrations notably improved ammonia utilization rates (AUR) and NH4+ and total nitrogen (TN) utilization efficiencies, peaking at 57% for SBR1 and nearly 100% for SBR2. Stoichiometric analysis showed a 7.5-fold increase in AUR (SRAO and anammox) in SBR1 following SO42− supplementation. However, the analysis for SBR2 indicated a shift towards SRAO and mixotrophic denitrification, with anammox disappearing entirely by the end of the study. Comparative assessments between SBR1 and SBR2 emphasized the impact of organic compounds (CH3COONa) on transformations within the N–S–C cycle. SBR1 performance primarily involved anammox, SRAO and other SO42− utilization pathways, with minimal S-dependent autotrophic denitrification (SDAD) involvement. In contrast, SBR2 performance encompassed SRAO, mixotrophic denitrification, and other pathways for SO42− production. The SRAO process involved two dominant genera, such as Candidatus Brocadia and PHOS-HE36.

  • Enhancing rheological muscle models with stochastic processes
    • Bartłomiej Zagrodny
    • Wiktoria Wojnicz
    • Michał Ludwicki
    • Robert Barański
    2024 Pełny tekst Acta of Bioengineering and Biomechanics

    Purpose: Biological musculoskeletal systems operate under variable conditions. Muscle stiffness, activation signals, and loads change during each movement. The presence of noise and different harmonic components in force production significantly influences the behaviour of the muscular system. Therefore, it is essential to consider these factors in numerical simulations. Methods: This study aims to develop a rheological mathematical model that accurately represents the behaviour of the actual muscular system, taking into account the phenomena described by the stochastic model in the form of stationary processes. Stochastic disturbances were applied to simulate variable conditions, in which musculo-skeletal system operates. Numerical simulations were conducted for two dynamic tasks, where we calculated the internal force generated by the system (task 1), and its displacement (task 2). These simulations were performed using two different datasets sourced from the literature. In the next step, simulation results were compared with our own experiment. Results: The considered mathematical model was successfully tuned and compared with both the literature data and our own experimental results. During the analysis of muscle model behavior, depending on the data source for model tuning, we observed distinct frequency characterized by a sine-type pattern and a higher frequencies marked by stochastic perturbations. Conclusions: The proposed model can be customized to simulate systems of varying sizes, levels of maximum voluntary contraction, and the effects of perturbations, closely resembling real-world data. The presented approach can be applied to simulate the behaviour of the musculoskeletal system as well as of individual muscles.