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CFD Code Parallelization on GPU and the Code Portability
No full textGoal of this paper is to develop a fully functional parallel Computational Fluid Dynamics (CFD) code that is optimized to run on a single Graphics Processing Unit (GPU). This is achieved by writing the code in FORTRAN and OpenACC (Open Accelerators), providing them with an easily portable, platform independent code. Existing CFD code is significantly modified to allow for parallel asynchronous execution. Also, due to strong recursive dependencies in Tridiagonal Matrix Algorithm (TDMA) solver, it is replaced with Jacobi, which provides fast execution in environments with large number of parallel cores. In this research a computer code for simulation of 2D flow of water through the axisymmetric channel is used as a base for development. The parallel code is executed on GPU, single, and multicore Central Processing Unit (CPU), and the execution times are compared between platforms. Even though that Jacobi solver performs worse on single core computers, compared to its Gauss-seidel counterpart, it is used to provide a baseline for comparison. In this work, it is shown that computation on finer grids takes less time on GPU than on CPU. The computation time increase with the number of cells in grid on GPU should follow the observed linear trend until the GPUs physical limitations are reached depending on memory size and core count. © 2024 Wiley-VCH GmbH
High-Responsivity Self-Powered Photoelectrochemical UV Photodetector Based on Integrated Self-Supporting SiC/ZnS Heterojunction Nanowire Arrays
No full textIn the realm of photodetector (PD) technology, photoelectrochemical (PEC) PDs have garnered attention owing to their inherent advantages. Advances in this field depend on functional nanostructured materials, which are pivotal in improving the separation and transport of photogenerated electron–hole pairs to improve device efficiency. Herein, a highly photosensitive PEC UV PD is built using integrated self-supporting SiC/ZnS heterojunction nanowire array photoelectrodes through anodization and chemical deposition. Compared with the original SiC nanoarrays, the optimized SiC/ZnS-25 nanoarrays exhibit high photocurrent density (Dph, 809.2 µA cm−2), rapid rise/decay times (τr/τd, 4/21 ms), high responsivity (Rλ, 1.226 A W−1), remarkable detectivity (D*, 2.517 × 1011 Jones), and large external quantum efficiency (EQE, 40.57%) under 375 nm UV light with a bias voltage of 0.6 V. Furthermore, SiC/ZnS-25 delivers excellent self-powered performance, with Rλ, D*, and EQE reaching 0.91 A W−1, 1.69 × 1011 Jones, and 30.24%, respectively. In addition, the device exhibits excellent long-term operation and aging stability under a bias voltage of 0.6 V and under self-powered conditions. The excellent photodetection behaviors of the SiC/ZnS PEC PD are mainly ascribed to the synergistic effect of the novel well-aligned nanowire geometry, heterojunction with ZnS nanofilms of optimal thickness, and integrated self-supporting configuration of the photoelectrode. © 2024 Wiley-VCH GmbH
Effect of Nanoparticles Type and Content on the Antimicrobial Activity of Magnetoelectric Polymer-Based Composites
No full textAntimicrobial materials are essential for the development of coatings for high traffic surfaces to prevent the adhesion and proliferation of microorganisms, playing a crucial role in infection control. In this study, different magnetoelectric nanocomposites exhibiting antimicrobial activity upon magnetic stimulation were developed by solvent casting. The nanocomposites, composed of poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] with different contents (10 and 20% wt) of CoFe2O4 (CFO) or Fe3O4 nanoparticles, were developed to respond to a variable magnetic field, mechanically stimulating the piezoelectric component of the material and inducing surface potential variations. The antimicrobial properties of these materials were evaluated by exposing them to different magnetic frequencies (0.3 and 1 Hz) in a custom-made magnetic bioreactor. The growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was significantly inhibited, particularly in the P(VDF-TrFE) nanocomposite with 20% CFO NPs, under magnetic stimulation at 1 Hz (bacterial cell viability ≈15%) compared to static conditions (bacterial cell viability ≈35%). This study highlights the potential of magnetic stimulation, in combination with magnetoelectric materials, as an effective strategy for the development of antimicrobial surfaces
Effect of catalyst loading on visible-light degradation of Acid Orange 7 by microwave-synthesized BiVO4 nanoparticles
No full textAzo dyes are among the most persistent classes of industrial pollutants, frequently resisting conventional treatment and motivating visible-light advanced oxidation approaches. This study investigates the degradation of Acid Orange 7 (AO7) using bismuth vanadate (BiVO4) nanoparticles synthesized via a rapid, energy-efficient microwave-assisted method (~98% yield). X-ray diffraction (XRD) confirmed a phase-pure monoclinic scheelite structure with an average crystallite size of ~19 nm, while transmission electron microscopy (TEM) showed uniform, near-spherical particles with minimal agglomeration. UV–Vis diffuse reflectance combined with Tauc's analysis (Kubelka–Munk transform, direct transition, n = 1/2) gave a band gap of 2.55 eV, consistent with visible-light activity of BiVO4. Photocatalytic experiments on 20 ppm AO7 (50 mL) were performed under a 300 W xenon light source at the native pH (4.5). Suspensions (10–20 mg BiVO4) were ultrasonicated for 15 min and equilibrated in the dark for 60 min; decolorization at 484 nm was monitored for 120 min. Increasing the catalyst mass from 10 to 15 mg raised AO7 removal to 77% at 120 min, whereas 20 mg provided only a marginal additional gain. Kinetics followed a pseudo-first-order model (R² = 0.996). The loading dependence reflects a balance between added active surface and light shielding/aggregation at higher solids. Under these conditions, ~15 mg per 50 mL is a practical loading for efficient visible-light-driven decolorization with pristine BiVO4.Twenty-Third Young Researchers' Conference Materials Science and Engineering, December 3-5, 2025, Belgrade, Serbia
Hybrid Polyaniline/rGO/AgNWs Composites for High-Performance EMI Shielding
No full textAs electronic devices and wireless systems continue to expand rapidly, electromagnetic interference (EMI) has become a pressing issue, impacting both the functionality of electronic components and human well-being. Conductive polymer composites have gathered attention for EMI shielding due to their lightweight nature, mechanical flexibility, and ability to overcome the drawbacks of traditional metallic and carbon-based materials. Among the most promising fillers, reduced graphene oxide (rGO) and silver nanowires (AgNWs) stand out, offering high electrical conductivity, low percolation thresholds, and uniform dispersion within polymer matrices. In this study, novel polyaniline-based composite materials for electro- magnetic interference (EMI) shielding were developed by incorporating reduced graphene oxide (rGO), silver nanowires (AgNWs), and their hybrid (rGO/AgNWs) into a polymer matrix. To obtain flexible films with enhanced mechanical properties, the synthesized composites were incorporated into a polycaprolactone matrix. Morphology of prepared films was examined using scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX), while molecular structure was analyzed by FTIR and Raman spectroscopy. Electrical properties relevant to EMI shielding were evaluated using a Vector Network Analyzer (VNA). The PANI/rGO/AgNWs composite is anticipated to exhibit excellent EMI shielding performance due to uniform filler dispersion and the conductive pathways formed by metallic nanowires within the PANI matrix. This results in enhanced electrical conductivity and effective shielding, even at low filler content and minimal thickness, demonstrating strong potential for practical electromagnetic protection applications.Twenty-sixth annual conference on material science (YUCOMAT 2025), Herceg Novi, Montenegro, 1-5 September 2025
From Ion Tracks to Nanoscale Holes in Oxide Semiconductors: Swift Heavy Ion Engineering of BiVO4 for Solar Water Splitting
No full textSwift heavy ion (SHI) irradiation with 150 MeV Xe ions (5 × 109 - 5 × 1011 ions cm-2) was used to tune the defect landscape and morphology of hydrothermally grown BiVO4 (BVO) thin films, aiming to enhance their photoelectrochemical (PEC) performance for the oxygen evolution reaction (OER). Irradiation induces residual stress, partial amorphization, and bismuth-rich hillocks over oxygen-depleted ion tracks. At the highest fluence, overlapping tracks and excessive defect accumulation cause irreversible performance loss. In contrast, lower fluences (5 × 109 and 1 × 1010 ions cm-2) generate controlled defects that initially trap charges but subsequently boost activity, increasing photocurrent density by 58.6% and 25.2%, respectively. Post-PEC analysis reveals evolution of latent ion tracks into nanoscale holes (up to 30 nm in diameter, 200 nm deep), with the 1 × 1010 ions cm-2 sample displaying the most uniform features, indicative of an optimal defect–stress balance enabling localized restructuring. These results demonstrate SHI irradiation as a precise nanoscale morpho-structural engineering tool, with the controlled creation of holes in oxide semiconductors offering pathways for cocatalyst or plasmonic integration to further enhance PEC efficiency.29th International Scientific Conference of Young Scientists and Specialists (AYSS-2025); 27-31 October 2025, Laboratory of Information Technologies of the Joint Institute for Nuclear Research (JINR), Dubna, Russia
Impact of seven-day regimen of intermittent theta burst stimulation (iTBS) on dendritic spine morphology and structural plasticity
No full text6th International Brain Stimulation Conference 23-26 February 2025 Kobe, Japa
Electrical Features of Liquid Crystal Composition Doped with Cobalt Ferrite: Possible Sensing Applications
No full textThe effects of CoFe2O4 nanoparticles on the properties of an electro-optical liquid crystal cell based on the nematic composition of 4-Cyano-4′-pentylbiphenyl (5CB) under the influence of different forms of bias voltage were studied. Detailed results were established for the application of sinusoidal voltages with various frequencies and amplitudes. At the input signal, with a frequency of 500 kHz, a resonant current increase was obtained in the electrical circuit, followed by a decrease in the current with an increase in the frequency. This indicates the formation of a consistent oscillatory circuit. The quality factor of the nanoparticle system does not depend on the amplitude of the controlled voltage. Liquid crystal cells with constant quality can be used in a number of devices and technologies, including extended sensing devices, where stable electrical properties are required. © 2025 by the authors
NADES-based preparation of Nd-TiO2/oxygen doped-g-C3N4 heterojunction with enhanced photocatalytic performances: Experimental investigation with theoretical explanation
No full textIn recent years, substantial research efforts have been directed toward developing materials with enhanced photocatalytic activity for wastewater treatment. Among the most sustainable and promising technologies for addressing dye-contaminated water, photocatalytic degradation has gained considerable attention. This study integrates these principles by designing a novel heterojunction photocatalyst comprising neodymium-doped titanium dioxide (Nd-TiO2) supported on an oxygen-enriched graphitic carbon nitride (O-g-C3N4) matrix. The catalyst was synthesized via a natural deep eutectic solvent (NADES)-based method, systematically characterized, and evaluated for water purification. Reactive Black 5, a commonly used textile dye, was selected as a model pollutant for degradation under visible-light irradiation. The influence of key parameters, including catalyst loading, the presence of a carbon matrix, initial pH, and reusability, was investigated to optimize performance. The Nd-TiO2 material supported by 10 % O-g-C3N4 achieved effective RB5 removal within 90 min, following pseudo-first-order kinetics. A degradation pathway was proposed based on DFT examination, offering mechanistic insights into the underlying photocatalytic process. The successful application of this system to real water samples highlights the feasibility of this green approach for practical environmental remediation. Additionally, the exceptional electrocatalytic properties of the synthesized material suggest its potential for further exploration in synthetic chemistry, materials science, and environmental applications
Enhanced polyphenolic extraction efficiency and antioxidant activity of sage using a deep eutectic solvent based on choline chloride and urea
No full textTraditional medicine has utilized sage to treat and prevent a wide range of illnesses. The aim of this study was to determine and compare the polyphenol content and antioxidative activity of sage leaves extracts made with choline chloride: urea mixed with 50% water (ChCl:U) and pure sage water extract (dH2O). Total phenolic content (TPC), total tannin content (TTC), and total flavonoid content (TFC) in extracts were determined. Radical scavenging capacity of sage extracts was measured using the DPPH and ABTS assays. It was demonstrated that the polarity of the solvent had distinct impacts on the extraction of polyphenols from sage leaves using the identical extraction process with ChCl:U and water. Higher polyphenol content (TPC and TTC) and radical scavenging properties against DPPH• and ABTS+• were observed in sage extract made with ChCl:U. TFC in both extracts was almost equal. Results indicated that choline chloride-based DES is an efficient solvent for sage leaf extraction as compared to water.ICCBIKG 2025 : 3rd International Conference on Chemo and Bioinformatics, September 25-26, 2025; Kragujevac, Serbia