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Chemical and isotopic genesis of fine and ultra-fine aerosols in the coastal urban atmosphere

science of the Total Environment 2025年 967卷 178823页

作者： GÓRKA, Maciej BEZYK, Yaroslav MALINOWSKA, Martyna SÓWKA, Izabela REIZER, Magdalena LEWANDOWSKA, Anita Institute of Geological Sciences Faculty of Earth Science and Environmental Management University of Wroclaw Cybulskiego 32 Wroclaw50-205 Poland Faculty of Environmental Engineering Wroclaw University of Science and Technology Plac Grunwaldzki 13 Wroclaw50-377 Poland Faculty of Physics and Applied Computer Science AGH University of Kraków Mickiewicza 30 Kraków30-059 Poland Faculty of Oceanography and Geography University of Gdańsk al. J. Pilsudskiego 46 Gdynia81–378 Poland Faculty of Building Services Hydro and Environmental Engineering Warsaw University of Technology Nowowiejska 20 Warsaw00-653 Poland

Particulate matter (PM) is one of the largest contributors to air pollution and is associated with several adverse health effects. In this study, we collected PM1 and PM2.5 samples in Gdynia (northern Poland) during five campaigns in January–March and September–October 2022. Analysis of the chemical composition of these aerosols (organic carbon [OC], elemental carbon [EC] and water-soluble ions) supplemented with their carbon isotope signatures (δ13CTC), meteorological parameters, HYSPLIT air masses backward trajectories and PCA-MLRA receptor modelling allowed us to recognize the significant differences in seasonal concentrations of both aerosol fractions and to identify the potential sources/processes that influenced their chemical composition. In general, the influence of both the anthropogenic sources, mainly related to fuel combustion and agricultural/fertilization activity, as well as natural sources, particular terrigenous was found. PCA-MLRA revealed that fuel burning contributed on average, with 77.9 % and 83.7 % to total PM1 and PM2.5 mass, respectively, while agricultural activities represented, 9.5 % and 9.1 % of PM1 and PM2.5 mass, respectively. Despite the location of the measurement station in the vicinity of the sea coastal zone, during the analysed period it was not found that the sea water was a dominant source of aerosols in both size fractions, contributed with 9.2 % and 4.6 % to total PM1 and PM2.5 mass, respectively. Regardless of the season several indicators – OC/EC, EC/TC, K+/TC and TC/SO42− − supported the important influence of coal burning, with a less important contribution from biomass burning. The maturation processes in the atmosphere were also important. For PM1 aerosols the clear 13C enrichment during the heating period was noticed, what was confirmed by isotope mass balance (Keeling plot approach, −25.05 ‰ ± 0.21 ‰ and − 25.90 ‰ ± 0.28 ‰ in the heating and vegetative seasons, respectively). It was associated with high coal usage for

关键词： Coal combustion

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Spin-lattice relaxation of NV centers in nanodiamonds adsorbed on conducting and non-conducting surfaces

arXiv

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arXiv 2025年

作者： Benedičič, Izidor Tanuma, Yuri Gosar, Žiga Anézo, Bastien Mrózek, Mariusz Wojciechowski, Adam Arčon, Denis Jožef Stefan Institute Jamova c. 39 Ljubljana1000 Slovenia Faculty of Mathematics and Physics University of Ljubljana Jadranska c. 19 Ljubljana1000 Slovenia Nantes University 2 Rue de la Houssinière Nantes France Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Prof. S. Lojasiewicza 11 Krakow30-348 Poland

The nitrogen-vacancy (NV) centers in nanodiamonds can be utilized as low-cost, highly versatile quantum sensors for studying surface properties in condensed matter physics through the application of relaxometry protocols. For such applications, a detailed knowledge of the intrinsic relaxation processes of NV centers in nanodiamonds is necessary. Here, we study the spin-lattice relaxation rates of NV ensembles in nanodiamonds with average diameters of 40 nm and 3 µm between room temperature and ∼ 6 K. The NV relaxation curves fit to a stretched-exponential form with a stretching exponent α ≈ 0.7, implying the large distribution of relaxation times of individual centers within nanodiamonds. We determine the Orbach-like scattering on phonons as the leading relaxation mechanism. Finally, we discuss the viability of nanodiamonds as surface sensors when deposited on a metallic substrate and emphasize the need for well-controlled surface preparation techniques. © 2025, CC BY.

关键词： Spin-lattice relaxation

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Glassforming liquid crystalline equimolar mixtures of MHPOBC and fluorinated compounds – structural, optical, and dielectric properties

arXiv

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arXiv 2025年

作者： Deptuch, Aleksandra Paliga, Anna Drzewicz, Anna Czerwiński, Michal Juszyńska-Galązka, Ewa Institute of Nuclear Physics Polish Academy of Sciences Radzikowskiego 152 KrakówPL-31342 Poland Faculty of Physics and Applied Computer Science AGH University of Kraków Reymonta 19 KrakówPL-30059 Poland Institute of Chemistry Military University of Technology Kaliskiego 2 WarsawPL-00908 Poland Research Center for Thermal and Entropic Science Graduate School of Science Osaka University Osaka560-0043 Japan

Three liquid crystalline equimolar mixtures are formulated, each containing the MHPOBC compound and the homolog from the 3FmHPhF6 series with m = 4, 5, and 6. The properties of the mixtures are investigated by differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, electro-optic measurements, and UV-Vis-NIR and dielectric spectroscopies. In all mixtures, the smectic A*, smectic C*, and smectic CA* phases are observed. Each mixture can be supercooled and forms the glass of smectic CA* at 225-238 K. The glass transition temperature decreases with the increasing CmH2m chain length in the 3FmHPhF6 molecule. The tilt angle in the smectic CA* phase reaches 36.5-37.5°. The selective reflection of light in the visible and near-infrared spectral ranges is observed, with a strong dependence of the reflected light’s wavenumber on temperature. © 2025, CC BY.

关键词： Chain length

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Effect of Valence Band Tail Width on the Open Circuit Voltage of P3HT:PCBM Bulk Heterojunction Solar Cell:AMPS-1D Simulation Study

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Chinese physics Letters 2015年第8期32卷 216-220页

作者： Bushra Mohamed Omer Department of Physics College of Science and ArtsTaif University Department of Applied Physics and Mathematics Faculty of Applied Science and ComputerOmdurman Ahlia University

The effect of the valence band tail width on the open circuit voltage of P3HT：PCBM bulk heterojunction solar cell is investigated by using the AMPS-1D computer program. An effective medium model with exponential valence and conduction band tail states is used to simulate the photovoltaic cell. The simulation result shows that the open circuit voltage depends Iinearly on the logarithm of the generation rate and the slope depends on the width of the valence band tail. The open circuit voltage decreases with the increasing width of the band tail. The dark and light ideality factors increase with the width of the valence band tail.

关键词： Effect of Valence Band Tail Width on the Open Circuit Voltage of P3HT:PCBM Bulk Heterojunction Solar Cell:AMPS-1D Simulation Study HT

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Efficiently Cooling Quantum Systems with Finite Resources: Insights from Thermodynamic Geometry

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Physical Review Letters 2025年第7期134卷 070401-070401页

作者： Philip Taranto Patryk Lipka-Bartosik Nayeli A. Rodríguez-Briones Martí Perarnau-Llobet Nicolai Friis Marcus Huber Pharnam Bakhshinezhad Department of Physics and Astronomy University of Manchester Manchester M13 9PL United Kingdom Department of Physics Graduate School of Science The University of Tokyo 7-3-1 Hongo Bunkyo City Tokyo 113-0033 Japan Department of Applied Physics University of Geneva 1211 Geneva Switzerland Institute of Theoretical Physics Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University 30-348 Kraków Poland Atominstitut Technische Universität Wien Stadionallee 2 1020 Vienna Austria Miller Institute for Basic Research in Science University of California Berkeley California 94720 USA Física Teòrica: Informació i Fenòmens Quàntics Departament de Física Universitat Autònoma de Barcelona 08193 Bellatera (Barcelona) Spain Institute for Quantum Optics and Quantum Information—IQOQI Vienna Austrian Academy of Sciences Boltzmanngasse 3 1090 Vienna Austria

Landauer’s limit on heat dissipation during information erasure is critical as devices shrink, requiring optimal pure-state preparation to minimize errors. However, Nernst’s third law states this demands infinite resources in energy, time, or control complexity. We address the challenge of cooling quantum systems with finite resources. Using Markovian collision models, we explore resource trade-offs and present efficient cooling protocols (that are optimal for qubits) for coherent and incoherent control. Leveraging thermodynamic length, we derive bounds on heat dissipation for swap-based strategies and discuss the limitations of preparing pure states efficiently.

关键词： Cooling

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Constrained Hybrid Metaheuristic Algorithm for Probabilistic Neural Networks Learning

arXiv

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arXiv 2025年

作者： Kowalski, Piotr A. Kucharczyk, Szymon Mańdziuk, Jacek Faculty of Physics and Applied Computer Science AGH University of Krakow al. A. Mickiewicza 30 Cracow30-059 Poland Systems Research Institute Polish Academy of Sciences ul. Newelska 6 Warsaw01-447 Poland AGH Doctoral School AGH University of Krakow al. A. Mickiewicza 30 Cracow30-059 Poland Faculty of Mathematics and Information Science Warsaw University of Technology Koszykowa 75 Warsaw00-662 Poland Faculty of Computer Science AGH University of Krakow al. A. Mickiewicza 30 Cracow30-059 Poland

This study investigates the potential of hybrid metaheuristic algorithms to enhance the training of Probabilistic Neural Networks (PNNs) by leveraging the complementary strengths of multiple optimisation strategies. Traditional learning methods, such as gradient-based approaches, often struggle to optimise high-dimensional and uncertain environments, while single-method metaheuristics may fail to exploit the solution space fully. To address these challenges, we propose the constrained Hybrid Metaheuristic (cHM) algorithm, a novel approach that combines multiple population-based optimisation techniques into a unified framework. The proposed procedure operates in two phases: an initial probing phase evaluates multiple metaheuristics to identify the best-performing one based on the error rate, followed by a fitting phase where the selected metaheuristic refines the PNN to achieve optimal smoothing parameters. This iterative process ensures efficient exploration and convergence, enhancing the network’s generalisation and classification accuracy. cHM integrates several popular metaheuristics, such as BAT, Simulated Annealing, Flower Pollination Algorithm, Bacterial Foraging Optimization, and Particle Swarm Optimisation as internal optimisers. To evaluate cHM performance, experiments were conducted on 16 datasets with varying characteristics, including binary and multiclass classification tasks, balanced and imbalanced class distributions, and diverse feature dimensions. The results demonstrate that cHM effectively combines the strengths of individual metaheuristics, leading to faster convergence and more robust learning. By optimising the smoothing parameters of PNNs, the proposed method enhances classification performance across diverse datasets, proving its application flexibility and efficiency. © 2025, CC BY-NC-ND.

关键词： Contrastive Learning

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NOMA-Based Ze-RIS Empowered Backscatter Communication with Energy-Efficient Resource Management

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IEEE Transactions on Communications 2025年

作者： Asif, Muhammad Bao, Xu Ihsan, Asim Khan, Wali Ullah Li, Xingwang Chatzinotas, Symeon Dobre, Octavia A. The School of Computer Science and Communication Engineering Jiangsu University Zhenjiang China The Department of Electrical Engineering University of Cambridge Cambridge United Kingdom University of Luxembourg Luxembourg City1855 Luxembourg The School of Physics and Electronic Information Engineering Henan Polytechnic University the Jiaozuo Key Laboratory of Crow-Sensing Network Jiaozuo454003 China The Department of Electrical and Computer Engineering Faculty of Engineering and Applied Science Memorial University St. John’sNLA1B 3X9 Canada

This manuscript introduces a novel energy-efficient optimization strategy for a zero-energy reconfigurable intelligent reflecting surface (Ze-RIS) supported backscatter communication system employing non-orthogonal multiple access (NOMA). The central objective is to maximize the energy efficiency of the system by optimizing the several key parameters, including the amplitude reflection coefficient of Ze-RIS, the reflection coefficients of the backscatter tags, transmit beamforming at the base station, and passive beamforming at the Ze-RIS node, while incorporating a practical non-linear energy harvesting model both for the Ze-RIS and backscatter nodes. The proposed algorithm addresses the complex non-convex problem through three stages. Firstly, the transmit beamforming vectors are determined by leveraging the semi-definite programming and successive-convex approximation, while handling the rank-1 constraint with the semi-definite relaxation. Secondly, we determine the amplitude reflection coefficient of Ze-RIS by leveraging the monotonicity property of the objective function. Simultaneously, we compute the reflection coefficients of backscatter tags using the Dinkelbach algorithm, Lagrange duality, and the sub-gradient method. Thirdly, we compute passive beamforming using successive-convex approximation and semi-definite programming techniques, achieving a rank-1 solution through the penalty-based method. Finally, the numerical simulations confirm the effectiveness of the proposed approach, demonstrating its superiority over the benchmark competitors with rapid convergence within a few iterations. © 1972-2012 IEEE. All rights reserved.

关键词： Beamforming

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Field distortion by a single cavity in HVDC XLPE cable under steady state

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High Voltage 2016年第3期1卷 107-114页

作者： Miao He George Chen Paul L.Lewin Faculty of Physics and Applied Science School of Electronic and Computer ScienceUniversity of SouthamptonSouthamptonUK

Electric field distribution in high voltage direct current(HVDC)cross-linked polyethylene(XLPE)cable at steady state is researched in this *** the condition that no cavity exists,equations describing the critical temperature difference for field reversal,and electric field distribution at steady state are *** the cable with cavity is studied via the finite element analysis method,2D and 3D model can be two possible *** comparison between these two models provides the reference for model selection so that the problem can be solved *** study field enhancement by a single air-filled cavity at steady state,some possibly influenced factors are considered,including the cavity location,cavity size,cavity shape,temperature difference and material *** equation describing field enhancement is given in the study.

关键词： XLPE cavity state

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Quasi Q-Balls in massless scalar fields

arXiv

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arXiv 2025年

作者： Romańczukiewicz, Tomasz Shnir, Yakov Faculty of Theoretical Physics Astronomy and Applied Computer Science Jagiellonian University Kraków Poland Instituto de Física de São Carlos IFSC/USP Universidade de São Paulo USP Caixa Postal 369 São Carlos-SPCEP 13560-970 Brazil

We study long-term evolution of radiating quasi-Q-balls in 1+1 dimensional models without mass threshold. Two different models are considered, the model with a rational modification of the usual Q-ball sextic potential and the model of a Q-ball in a box with outgoing boundary conditions. We find that the outgoing boundary conditions modify the angular frequency of quasi-Q-balls which becomes complex-valued. The quasi-Q-balls decay initially very similarly, but in the last stage quasi-Q-balls in a box become linear resonances, whereas in the rationally modified model, they decay according to some power law. © 2025, CC BY.

关键词：

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Design of Monopole Transparent Antenna for Satellite Internet Aboard Aircraft

Design of Monopole Transparent Antenna for Satellite Interne...

引用

International Electrical Engineering Congress (iEECON)

作者： Tawan Thianthong Patchadaporn Sangpet Chatree Mahatthanajatuphat Nipont Tangthong Chawalit Rakluea Nonchanutt Chudpooti Thinnawat Jangjing Supphakon Khongchon Siam Airport Ground Services Co. Ltd. Bangkok Thailand Department of Electronics and Telecommunication Engineering Rajamangala Faculty of Engineering University of Technology Thanyaburi Thailand Department of Electrical and Computer Engineering Faculty of Engineering King Mongkut's University of Technology North Bangkok Bangkok Thailand Department of Industrial Physics and Medical Instrumentation Faculty of Applied Science King Mongkut's University of Technology North Bangkok Bangkok Thailand

ISBN: (数字)9798331543952

ISBN: (纸本)9798331543969

This research presents the design of a transparent antenna for satellite internet aboard aircraft. The presented antenna comprises a triangular arrow monopole antenna fed by a tapered microstrip transmission line. It employs a polycarbonate composite substrate with a dielectric constant (εr) of 2.8 and a thickness (h) of 1 mm. The proposed transparent antenna achieves a bandwidth in the frequency range of 10.42–22.70 GHz, with an omnidirectional radiation pattern and an average gain of 2.57 dBi, effectively covering the Ku band for satellite internet applications. The antenna design was simulated using electromagnetic wave CST simulation software, and a prototype antenna was fabricated. The designed antenna exhibits a reflection coefficient of less than -10 dB throughout the 10.7–12.7 GHz frequency range, which is the operational frequency range for satellite internet and is an acceptable value in research terms. Moreover, a conductor with a thickness of 0.035 mm sits on a composite substrate material to form the antenna structure for satellite internet aboard aircraft. We need to study and apply various techniques to further enhance the antenna's performance in future designs.

关键词： Satellite antennas Airplanes Satellites Microstrip antennas Military aircraft Internet Substrates Gain Antenna radiation patterns Transmission line antennas

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