Browsing by Issue Date, starting with "2026"

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Access status: Open Access ,
The Influence of Modified Inorganic Binders Intended for 3D Printing on Selected Properties of Thermally Cured Moulding Sands – Conventionally and with Microwaves
(AGH University Press, 2026) Halejcio, Dawid M.; Major-Gabryś, Katarzyna
This study determined the impact of thermal curing on the basic properties of moulding compounds made with commercial inorganic binders and binders based on them, modified for use in 3D printing technology (Binder Jetting). Two inorganic binders based on sodium silicate and a binder based on aluminosilicates were tested. As part of the work, the parameters for thermal curing of the mixtures were selected: for curing in a dryer, the best properties were obtained for mixtures containing 2.0 p.p.w. of binder cured for 10 min at 160°C. In the case of microwave curing, the best properties were obtained for moulding sands containing 2.0 p.p.w. of binder cured for 6 min at a device power of 800 W. The tests showed that the basic properties of moulding compounds with binders developed on the basis of commercial binders for use in 3D printing technology, thermally cured in a dryer, do not differ significantly from the properties of compounds with commercial binders. In the case of microwave curing, a reduction in the strength of compounds with new binders was observed in relation to compounds with classic binders. Thermal deformation tests of compounds with classic and modified binders confirmed the typical behavior observed for inorganic systems. It was proven that new, modified inorganic binders developed for 3D printing of moulds and cores using Binder Jetting technology can be used as binding materials in thermally cured moulding sands. Both thermal curing methods were assessed as suitable for curing moulding compounds with new binders.
Access status: Open Access ,
A Comparative Analysis of Low Carbon Road Transport Policies between Poland and India: A Systematic Literature Review Using Prisma
(Wydawnictwa AGH, 2026) Choudhury, Taniya; Aslanoğlu, Rengin
The road transport industry is one of the largest carbon-emitting sectors globally. Consequently, it is important to assess the development of the low-carbon policy literature to decarbonize the transportation sector. This study analyzes the low-carbon road transport (LCRT) policies in a developed country, Poland, and a developing country, India, over the past two decades – two countries with distinct socioeconomic contexts but similar environmental objectives. A total of 84 studies were identified through Scopus, Google Scholar, Research Rabbit, and government repositories. Of these, 39 manuscripts met the selection criteria and were included in the review. The PRISMA 2020 checklist was used for methodological evaluation. The findings indicate that Poland outperforms India in technological advancement, infrastructure development, road safety, and digitalization. Both countries need to align their policymaking trajectories with public participation and adopt a multidimensional, people-centric approach. A notable gap in the existing literature is identified: this study provides an in-depth analysis focused exclusively on low-carbon road transport, while broader transportation services remain outside the scope of the research.
Access status: Open Access ,
Modulating Surface Properties and Osteoblast Responses in Bone Regeneration via Positive and Negative Charges during Electrospinning of Poly(L‑lactide-co-ε-caprolactone) (PLCL) Scaffolds
(2026) Marszalik, Katarzyna; Polak, Martyna; Berniak, Krzysztof; Knapczyk-Korczak, Joanna; Szewczyk, Piotr K.; Marzec, Mateusz M.; Stachewicz, Urszula
Wydział Inżynierii Metali i Informatyki Przemysłowej
The global demand for faster and more effective bone regeneration calls for biomimetic scaffolds that actively guide cell behavior beyond providing structural support. Electrospinning offers unique opportunities to tailor scaffold properties, yet the influence of positive and negative voltage polarities during fabrication on cell−material interactions remains largely unexplored. Here, we investigate poly(L-lactide-co-ε-caprolactone) (PLCL) scaffolds, a statistical copolymer combining strength and elasticity, produced under positive (PLCL+) and negative (PLCL−) polarity. Both scaffold types display comparable morphologies and bulk chemistry. However, X-ray photoelectron spectroscopy reveals charge dependent surface chemistry, with PLCL− enriched in O C and O−C groups. Zeta potential results highlight pronounced voltage polarity effects under aqueous conditions at pH 7.5, showing −29.19 mV for PLCL+ and −34.77 mV for PLCL−. Biologically, both scaffolds support rapid osteoblast attachment, with robust filopodia and collagen type I deposition by day 14. Strikingly, PLCL+ scaffolds promote deeper cellular infiltration and broader cytoskeletal distribution, whereas PLCL− scaffolds enhance proliferation, but with a flatter cell morphology. These findings reveal that subtle, charge-driven surface chemical differences in random copolymer scaffolds profoundly modulate osteoblast behavior. This work identifies electrospinning voltage polarity as a powerful yet underutilized design parameter for engineering next-generation scaffolds for bone tissue regeneration.
Access status: Open Access ,
Determination of the Heat Transfer Coefficient in the Isothermal Quenching Process of ADI Cast Iron Cooled with Water Mist
(Akademia Górniczo-Hutnicza, 2026) Burbelko, Andriy A.; Stręk, Piotr
Isothermal quenching of austempering cast iron (ADI) castings requires that, after austenitization the casting must be rapidly cooled to the temperature of isothermal austenite decomposition. The cooling rate throughout the entire volume of the heat-treated product must be high enough to prevent pearlitic transformation. At the same time, the temperature of the cooled surface must not decrease below the martensitic transformation start temperature Ms. The cooling rate of the casting surface is determined by factors such as the temperature difference between the surface of the cooled casting and the cooling medium, the thermal conductivity of cast iron, the heat transfer coefficient, and the wall thickness of the treated casting. In the case of cooling with water mist, the heat transfer coefficient depends on the temperature of the cooled surface. To control the cooling process of castings using water mist, information about this relationship for the temperature range of 200–800°C is needed. Available scientific publications on this subject contain contradictory data. Therefore, a measuring station was built with the ability to set the temperature of the cooled surface. The station includes a measuring system that allows the measurement of the heat flux flowing from the heating element into the environment. The result of the research is the measurement of the relationship between the temperature of the cooled surface and the heat transfer coefficient. The values obtained will be used in the future to build a numerical model of ADI castings heat treatment. This work may contribute to the future replacement of salt baths (currently used for fast cooling and austempering) with water mist spraying. In this case, the low-temperature operation of austenite decomposition can be performed without the use of salt a bath.
Access status: Open Access ,
Controlled exsolution-dissolution in double perovskites enables symmetrical-capable high-performance SOFC electrodes
(2026) Lach, Jakub; Zheng, Kun; Radu, Cristian; Kryński, Marcin; Gogacz, Michał; Ling, Yihan; Klimkowicz, Alicja; Łapiński, Marcin
Wydział Energetyki i Paliw
In situ exsolution has emerged as a powerful strategy for tailoring fuel electrode catalysts in solid oxide fuel cells (SOFCs), yet its integration with reversible exsolution-dissolution processes and its application to symmetrical-capable electrode design remain largely unexplored. Here, we demonstrate controlled exsolution-dissolution in nanofiber double perovskites as a rational route to engineer high-performance SOFC electrodes operable in both symmetrical and anode-supported configurations. $Sm_{0.9}Ba_{0.9}Mn_{1.8−x}Fe_{x}Co_{0.1}Ni_{0.1}O_{5+δ}$ nanofiber perovskites enable composition-dependent control of nanoparticle evolution. Under reducing conditions, socketed Co–Ni–Fe alloy nanocatalysts exsolve and partially embed into the perovskite lattice, while oxidation induces their transformation into $Fe_{3−x−y}Ni_{x}Co_{y}O_{4}$-type hollow core–shell nano-oxides via a Kirkendall-type mechanism. The nanofiber architecture promotes smaller and more densely distributed nanoparticles compared to powders, enhancing catalytic activity and redox stability. The optimized composite electrode delivers a low polarization resistance of 0.046 Ω cm2 at 800 °C. Anode-supported cells achieve a peak power density of 1112 mW cm−2 at 850 °C and 877 mW cm−2 at 800 °C, while symmetrical cells deliver 816 mW cm−2 at 800 °C with stable operation. This work establishes controlled exsolution-dissolution as a versatile platform for designing symmetrical-capable high-performance SOFC electrodes and highlights hollow core–shell nanostructure engineering as a powerful strategy for durable solid oxide electrochemical systems.
Access status: Open Access ,
Systems of differential inclusions with competing operators and variable exponents
(Wydawnictwa AGH, 2026) Vetro, Francesca; Efendiev, Rakib
In this paper, we study a system of differential inclusions with Dirichlet boundary condition, involving competing operators and variable exponents. More precisely, we investigate the existence of both generalized solutions and weak solutions to the problem under consideration. In order to archive our results, we make use of approximation through finite dimensional subspaces via a Galerkin basis along with minimization and nonsmooth analysis.
Access status: Open Access ,
Quaternionic Quantum Mechanics: the Particles, Their q-Potentials and Mathematical Electron Model
(AGH University Press, 2026) Bożek, Bogusław; Danielewski, Marek; Sapa, Lucjan
In this work we show the quaternionic quantum descriptions of physical processes from the Planck to macro scale. The results presented here are based on the concepts of the Cauchy continuum and the elementary cell at the Planck scale. The structurally symmetric quaternion relations and the postulate of the quaternion velocity have been important in the present development. The momentum of the expansion and compression $u̇_{0}(t, x)$ is the consequence of the scalar term $\sigma_{0}(t, x)$ in the quaternionic deformation potential. The quaternionic $G_{0}(m)(σ_{0} + \hat{\textstyle \phi} )$, vectorial $G_{0}(m) \hat{\textstyle \phi}$ and scalar $G_{0}(m)\sigma_{0}$ propagators are used to generate the second order PDE systems for the proton, electron and neutron. A mathematical model of an electron is formulated. It is described by the hyperbolic-elliptic partial differential system of quaternion equations with the initial-boundary conditions. The boundary conditions are generated by the quaternion energy flux that is found with the use of the Gauss theorem, the Cauchy–Riemann derivative and other mathematical formulas. The rigorous assessment of the second order PDE systems allows the proposal of two second order PDE systems for the $u$ and $d$ quarks from the up and down groups. It was verified that both the proton and the neutron obey experimental findings and are formed by three quarks. The proton and neutron are formed by the $d$-$u$-$u$ and $d$-$d$-$u$ complexes, respectively. The u and d quarks do not comply with the Cauchy equation of motion. The inconsistencies of the quarks’ PDE with the quaternion forms of the Cauchy equation of motion account for their short lifetime and the observed Quarks Chains. That is, they explain the Wilczek phenomenological paradox: Quarks are Born Free, but everywhere they are in Chains.
Access status: Open Access ,
Assessing urban growth toward Earthquake-hazard zone in Yogyakarta and Bantul, Indonesia
(Wydawnictwa AGH, 2026) Miladan, Nur; Istanabi, Tendra; Suminar, Lintang; Rizal Fernandita Pamungkas, Muhammad; Settyawan, Vicky Dwi; Wijayanto, Arifian Dwi
Bantul and Yogyakarta are regions with earthquake-hazard risks in Indonesia. The earthquake that occurred in 2006 produced deaths, high economic losses, and significant damages to the housing and infrastructure. This research aimed to assess the urban growth in the earthquake-hazard zone in Bantul and Yogyakarta. The study used the remote sensing method of nighttime light (NTL), zonal statistics, and ClockBoard zone analysis. The combination of these analysis techniques for linking urban growth and earthquake hazards has not been widely discussed by previous studies. The earthquake- hazard data was retrieved from the United States Geological Survey website; meanwhile, the NTL data was based on the Visible Infrared Imaging Radiometer Suite (VIIRS) satellite. The results indicated that those zone segments at very high earthquake- hazard levels were also areaswith night-light intensities of more than ten units (meaning increasing urban growth). Based on these facts, local governments should evaluate spatial planning to limit the density of built-up areas in earthquake- hazard areas and ensure the effective implementation of urban sustainability and resilience.
Access status: Open Access ,
Time-Frequency Token Advantage Clipping for Training Efficient Large Reasoning Model
(2026) Bao, Rong; Wang, Bo; Li, Hongyu; Zheng, Riu; Wang, Xiao; Rutkowski, Leszek; Zhang, Qi; Ding, Liang; Tao, Dacheng
Wydział Informatyki
Long Chain-of-Thought (CoT) reasoning enhances large reasoning models’ performance but suffers from severe inefficiencies, as models often overthink simple problems or underthink complex ones. Current sequence-level optimizations, like length penalties, are too coarse-grained to distinguish core logic from verbose language, precluding the necessary token-level control for efficient reasoning CoT. To overcome these limitations, we introduce Time-Frequency token Advantage Clipping (TFAC), a novel training framework designed to build efficient large reasoning models via token-level interventions. Specifically, TFAC functions along two dimensions: 1) The Frequency Dimension: It discourages inefficient loops and encourages deeper exploration by dynamically reducing the advantage scores of high-entropy tokens that are repeatedly generated within a single reasoning path. 2) The Time Dimension: It reduces excessive overthinking of the system by establishing a historical baseline for the occurrence count of each critical token in previously successful trajectories, and clipping the advantages of tokens that exceed this baseline during training. Crucially, to preserve the model’s exploratory capabilities on novel problems, this suppression mechanism is automatically disabled when no historical record of success is available. Experiments conducted on the Deepseek-Distill-32B and Qwen3- 8B models show that TFAC outperforms leading baseline methods, improving performance by 2.3 and 3.1 percentage points, respectively, while simultaneously reducing inference costs by 35% and 28% in scenarios where correct answers are generated. These results validate the significant efficacy of TFAC in training large reasoning models that are both powerful and highly efficient. The source code and datasets used in this study are available at https://github.com/rbao2018/TFAC.
Access status: Open Access ,
Bridging the Tokenizer Gap: Semantics and Distribution-aware Knowledge Transfer for Unbiased Cross-Tokenizer Distillation
(2026) Wang, Huazheng; Jing, Yongcheng; Sun, Haifeng; Wang, Jingyu; Liao, Jianxin; Rutkowski, Leszek; Tao, Dacheng
Wydział Informatyki
Cross-tokenizer knowledge distillation, where the teacher and student employ different tokenizers, is becoming increasingly prevalent, yet it poses underexplored challenges: existing methods fail to capture the rich knowledge encoded in teacher logits, as evidenced by the neglect of semantic information, inaccurate and biased logit alignment, and discarding distributional structure—ultimately leading to unfavorable distillation. To address these issues, we propose SEDI, a semantics and distribution-aware knowledge transfer framework tailored for cross-tokenizer distillation. To preserve factual knowledge, SEDI employs bipartite graph-based alignment at the tokenization level and a sliding window re-encoding strategy at the vocabulary level, enabling unbiased transfer of the teacher’s next-token predictions into the student’s vocabulary space. To further retain distributional information, we align the student’s entropy with that of the teacher by incorporating the student’s own logits during training, which helps to mitigate the exposure bias problem. Experiments on ten datasets across three task domains and five different teacher-student model pairs with varying vocabulary sizes demonstrate that SEDI delivers substantial improvements, with gains of up to 19.8 .
Access status: Open Access ,
Geologic control of soil-infiltration rate based on artificial neural network models
(Wydawnictwa AGH, 2026) Sulistyo, Totok; Bahagiarti Kusumayudha, Sari; Cahyadi, Tedy Agung; Fajar, Reza Adhi; Kiptiah, Mariatul
The interconnected porosity of soil provides conduit channels for the downward infiltration of water into the subsurface; this occurs in soil layers and within soil-less areas or geologic formations. The lithology and geological structure significantly influence the infiltration capacity of soils and are crucial in determining whether the infiltration water continuously reaches an aquifer or becomes stagnant in the saturated soil. An artificial neural network (ANN) algorithm was employed to model the actual infiltration rate, incorporating soil texture and soil moisture along with geological scores as inputs and actual infiltration rates as outputs. This study aimed to quantify qualitative geological data and incorporate it into ANN model parameters. The development of the ANN infiltration model involved two serial trial-and-error experiments to determine the optimal number of nodes in the hidden layer, ranging from nodes c(4,2) to c(12,2), one serial experiment withgeological input, and the other without geological input. Throughout the model testing, metrics such as MAE, RMSE, and MSE were recorded, and the first and second optimum models were identified when employing c(9,2) nodes of hidden layers. The resulting model can be used to predict actual infiltration and will be beneficial for hydrometeorological-disaster mitigation and city-development planning.
Access status: Open Access ,
Anisotropic singular logistic equations
(Wydawnictwa AGH, 2026) Da Silva, João Pablo Pinheiro; Failla, Giuseppe; Gasiński, Leszek; Papageorgiou, Nikolaos S.
We consider a parametric Dirichlet problem driven by the anisotropic $(p,q)$-Laplacian and a reaction with a singular term and a superdiffusive logistic perturbation. We prove an existence and nonexistence theorem which is global with respect to the parameter $\lambda\gt 0$.We consider a parametric Dirichlet problem driven by the anisotropic $(p,q)$-Laplacian and a reaction with a singular term and a superdiffusive logistic perturbation. We prove an existence and nonexistence theorem which is global with respect to the parameter $\lambda\gt 0$.
Access status: Open Access ,
From Farmland to Cityscape: Urban Growth Simulation in Surkhet Valley, Nepal Using Remote Sensing and CA-Markov Modeling
(Wydawnictwa AGH, 2026) Budha, Padam Bahadur; Bhardwaj, Ashutosh; Thapa, Rajesh Bahadur
Urbanization is rapidly transforming the spatial and socioeconomic landscape of many emerging cities in Nepal, yet relatively little research has explored these dynamics outside the Kathmandu Valley. This study applies a cellular automata-Markov (CA-Markov) model to simulate and predict land use and land cover (LULC) changes in Surkhet Valley, the core of Birendranagar Municipality, one of Nepal’s fastest-growing urban centers. Using Landsat imagery from 1999, 2009, and 2019, alongside spatial and socioeconomic factors, the model captures historical LULC transitions and projects future changes for the years 2029, 2039, and 2049. Model validation was conducted against the 2019 classified LULC map, yielding an overall agreement of 80.65% and a standard kappa statistic of 70.31%, confirming the model’s predictive reliability. Results indicate a clear trajectory of urban expansion at the expense of agricultural land. Built-up surfaces is projected to more than double – from 12.43 km² in 2019 to 31.38 km² in 2049, while cultivated land is expected to decline by over 20 km² in the same period. Spatial analysis shows urban growth intensifying around existing centers, highways, and transitional ecotones between forest and cultivation zones. Compared to similar studies in Kathmandu and Biratnagar, Surkhet exhibits a higher normalized rate of urban expansion, highlighting its emerging role in regional development. This research underscores the value of remote sensing and spatial modeling in urban planning and land management. The findings provide essential insights for policymakers to guide sustainable development in Surkhet and other rapidly urbanizing areas across Nepal.
Access status: Open Access ,
p-type graphitic carbon nitride with boron bridge atoms designed for photoelectrochemical conversion of CO2
(2026) Mech, K.; Sławek, A.; Podborska, A.; Abdi, G.; Muzaffar, S.; Jarczewski, S.; Sokołowski, K.; Musielak, B.; Cechosz, E.; Janioł, M.; Szaciłowski, K.; Ponce de Leon, C.
Akademickie Centrum Materiałów i Nanotechnologii
Here, we report the results of studies dedicated to a synthesis of a series of graphitic carbon nitride materials doped with different amounts of boron, designed for photoelectrochemical conversion of CO2. The crystallographic structure of B-doped and pure heptazines was analyzed using XRD, while their chemical structure was analyzed using NMR, XAS, XPS, and FTIR spectroscopy. Based on of experimental spectra and DFT-based ones, we proved that boron in the polyheptazine structure is incorporated through the substitution of N atoms located only in bridge positions. The carbon nitride materials were also characterized in terms of their band structure based on the results of DRS spectroscopy, Mott-Schottky analysis, and DFT modelling. The experimental band gap energies and the decrease of band gap values resulting from the presence of boron bridge atoms were also confirmed by DFT calculations. The localization of valence and conduction bands indicates, along with p-type conductivity resulting from the presence of boron in these specific sites, that B-doped g-C3N4 may be utilized for light-supported PEC conversion of CO2. Photoluminescence measurements demonstrate more effective charge separation and significantly longer charge carrier lifetime resulting from the incorporation of boron. Finally, photocurrent spectroscopy showed that the material containing 2.5 at. % of B (B1–CN) generates photocurrent of the highest intensity of -0.99 μA in CO2-saturated 0.5 M KHCO3, making it the most promising one for photoelectrochemical conversion of CO2. The GC-MS/TCD analysis of syngas produced during photoelectrochemical CO2 reduction confirmed the formation of H2 and CO.
Access status: Metadata only ,
Planowane!
Zgrzewanie tarciowe z mieszaniem materiału (FSW) wysokowytrzymałych stopów aluminium obrabialnych cieplnie ze stopami nieobrabialnymi cieplnie
(Wydawnictwa AGH, 2026) Kalemba-Rec, Izabela
Access status: Open Access ,
The Presence of Rice Fields Amid Urban Expansion in a Medium-Sized City: A Case Study of the Surakarta Suburban Area
(Wydawnictwa AGH, 2026) Musthofa, Zaini; Buchori, Imam
Urban expansion has become the most significant threat to rice fields, particularly in medium-sized cities. Surakarta is a medium-sized city experiencing rapid growth, surrounded by regencies that are also undergoing urban expansion. This study aims to investigate the presence of rice fields under the pressures of urban expansion dynamics over a 32-year multitemporal period covering 1990, 1995, 2000, 2005, 2010, 2015, 2020, and 2022. This research utilized remote sensing data processed through Geographic Information Systems (GIS). Supervised classification was applied to identify land cover over the 32-year period, including the extent of rice fields. The average annual urban expansion rate (AUER) and urban expansion intensity index (UEII) analyses were used to determine urban expansion’s magnitude, speed, and direction. This study found that the most significant and fastest rate of urban expansion in Surakarta City occurred between 2020 and 2022. The results also showed that areas adjacent to the urban core (Surakarta City) experienced greater expansion speed than areas located farther away. Urban expansion pressure also resulted in a 40% loss of rice fields, with Klaten District experiencing the greatest loss. Maintaining rice fields in peri-urban areas can provide dual benefits by supplying rice for the city while preserving the local ecosystem. The dynamics of urban expansion in the Surakarta urban agglomeration, as revealed by this research, are essential for sustainable spatial planning in the region.
Access status: Open Access ,
Integrating water indices and cloud-based engine for change detection of aquaculture areas in Lampung, Indonesia
(Wydawnictwa AGH, 2026) Iswari, Marindah Yulia; Supriyadi, Indarto Happy; Nurdiansah, Doni; Anggraini, Kasih; Nurkhalis, Rahili; Suyarso
Population expansion and climate change have significantly affected the coastal environment in Lampung, Indonesia, mainly through the conversion of mangroves into shrimp-farming ponds. This transformation requires effective monitoring to evaluate its impacts on coastal ecosystems and local livelihoods, as shrimp farming is a major income source in East Lampung. This research improves aquaculture detection and monitoring along the eastern coast of Lampung by integrating several waterindices such as the normalized difference water index (NDWI), modified NDWI (MNDWI), water ratio index (WRI), and a newly developed water index (WI), within the cloud-based Google Earth Engine (GEE) platform to capture spatial and temporal variations. Reference data were derived from the 2019 Regional Medium-Term Development Planning Document (RPJMD) and high-resolution Google Earth imagery for accuracy assessment. Results showed that WRI combined with the Otsu’s thresholding method achieved the highest performance, with an overall accuracy (OA) of 93.3% and a kappa coefficient (κ) of 86.7%. Analysis from 2018 to 2022 showed a decline in aquaculture area from 8,407.35 ha to 3,415.50 ha, aligned with statistical data on shrimp production, which decreased from 24,202 t to 8,041 t. These results indicate that the method provides a rapid and effective tool for detecting aquaculture changes, enabling local authorities to strengthen coastal management for sustainable development, ecosystem protection, and livelihood support.
Access status: Open Access ,
High-Volume Return Premium on the Warsaw Stock Exchange: evidence, drivers, and strategy design
(Wydawnictwa AGH, 2026) Sieradzan, Olga; Wójtowicz, Tomasz
This paper investigates the High-Volume Return Premium (HVRP) on the Warsaw Stock Exchange from 2002 to 2023. Building on prior research, it tests whether an unusually high trading volume predicts short-term return anomalies. Using daily data and long-only strategies based on relative trading volume, the study confirms the existence of the HVRP, with the strongest effects observed over one-day horizons, particularly for mid-cap and low-priced stocks. The premium weakens with longer holding periods and lower trading activity. These findings indicate that trading volume carries predictive information in an emerging market context and that volume-based signals can generate exploitable short-term return patterns. However, practical constraints such as transaction costs may limit the real-world profitability of such strategies.
Access status: Open Access ,
New type of composite hydrogel based on natural polysaccharides and sodium polyacrylate for the production of fire-resistant fabrics
(2026) Osabe, Ryoko; Mastalska-Popławska, Joanna; Rutkowski, Paweł; Suematsu, Hisayuki; Kata, Dariusz; Szumera, Magdalena; Majka, Tomasz M.
Wydział Inżynierii Materiałowej i Ceramiki
Flexible and fire-resistant hydrogel–cotton fabric composites doped with ceramic fire retardants were obtained by the immersion method. Among the analyzed mixtures, the samples based on sodium polyacrylate, which provided the best degree of penetration and subsequent intumescence, and those containing magnesium hydroxide in their composition had the best fire-resistant parameters. This was confirmed based on TG/DSC and DMA thermal analysis, PCFC measurements, reaction to fire test results, and SEM microphotographs. The MIR spectroscopic analysis additionally proved that the fire-retardant mechanism is based on the creation of an intumescent structure strengthened by the interaction of fire retardants with various functions, such as hydroxides, which, during decomposition, create a protective char around the material. We believe that these results will contribute to the development of special fabrics with fire-retardant properties.
Access status: Open Access ,
Comparative Physicochemical Characterization of Electrospun PCL, PLLA, and PLCL Scaffolds and Cell Responses for Tissue Engineering Applications
(2026) Polak, Martyna; Neela, Nagalekshmi Uma Thanu Krishnan; Berniak, Krzysztof; Knapczyk-Korczak, Joanna; Szewczyk, Piotr K.; Marzec, Mateusz M.; Stachewicz, Urszula
Wydział Inżynierii Metali i Informatyki Przemysłowej
In tissue engineering, electrospun scaffolds are valued for their tunable features, which direct cell behavior. Within this study, we electrospun scaffolds from three common polyesters: polycaprolactone (PCL), poly(L-lactic acid) (PLLA), and poly(lactide-co-caprolactone) (PLCL), to identify differences in cell–material interactions. PLLA fibers had the largest average diameter (2.6 ± 0.2 µm), PLCL fiber diameter was intermediate (2.2 ± 0.5 µm), and PCL was the smallest (1.1 ± 0.6 µm). Additionally, X-ray photoelectron spectroscopy (XPS) revealed distinct surface chemistries that are correlated with streaming potential results at pH 7.4. PLCL fibers showed the most negative zeta potential (−36.4 ± 0.7 mV), followed by PLLA (−28.4 ± 0.8 mV) and PCL (−24.0 ± 0.5 mV). Mechanical testing indicates the highest strength for PLCL mats (5.6 ± 0.9 MPa), then PLLA (3.5 ± 0.3 MPa) and PCL (1.9 ± 0.1 MPa). Cell studies indicated lower initial adhesion of osteoblasts on PLCL (∼53%↓) and PLLA (∼73.6%↓) vs. PCL, likely reflecting PCL scaffold morphology; however, viability at 3 and 7 days was significantly higher on PLCL and PLLA. Microscopy studies confirmed greater filopodia and cell spreading on PLCL and PLLA. Overall, all three are suitable scaffold materials, with PLCL and PLLA supporting cytoskeleton organization and viability better.