bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical diagnostics of vacuum arcs in the process of DC interruption
Authors: Tang Q , Maede Y , Sato M , Kumada A , Jia S 
Published: September 2024

Abstract
Vacuum circuit-breakers (VCBs) are commonly used in emerging mechanical DC circuit-breakers. The electrical performance of VCBs in DC interruption duties has been extensively investigated, but basic physics such as the excitation temperature of plasma species, electron/vapor densities and emission of droplets in such applications were rarely reported. In this paper, we focus on how the short high frequency (HF) current pulse affects erosion of electrodes as well as generation of flying droplets by using laser shadow photography. Spectroscopy was adopted to obtain spectra and calculate the excitation temperature of CuI. Shack–Hartmann wavefront sensors were applied to measure neutral and electron density, in tests where di/dt, breaking current and the direction of the injected HF current varied. Indeed, the in-phase injection of the HF current caused an intense arc, but the pulse was too short to make either the cathode or anode melt. Since the plasma is in a nonequilibrium state, the excitation temperature of CuI is relatively low. Electron densities in different tests all approach similar values right before current zero. Neutral densities show strong fluctuation and independence on instantaneous current.
Plastic deformation mechanism of γ phase Fe–Cr alloy revealed by molecular dynamics simulations
Authors: Peng Peng , Lai Wensheng 
Published: September 2024

Abstract
Due to their outstanding mechanical properties, anti-corrosion properties, and anti-irradiation swelling properties, Fe–Cr alloys have been fully improved and developed for nuclear energy applications as structural materials. To ensure the performance stability of γ-phase Fe–Cr alloys, the present study adopted molecular dynamics (MD) simulations to explore the plastic deformation mechanism of these alloys. The slip model was constructed, and the generalised stacking fault energy (GSFE) and Peierls–Nabarro (P–N) equations were solved, revealing that {110}<111> is the preferentially activated slip system. The twinning model was constructed and the generalised plane fault energy was solved, demonstrating that twinning is preferred over slipping in the {112}<111> system. The above findings are also verified through MD simulations in which Fe–Cr specimens are stretched along the [100] direction. In addition, in the 15 at.%–25 at.% Cr range, an increase in the Cr content has a negative effect on slip but a positive effect on twin formation.
A frequency steerable electromagnetic acoustic transducer
Authors: Martinho Lucas M , De Marchi Luca , Kubrusly Alan C 
Published: September 2024

Abstract
Electromagnetic acoustic transducers (EMATs) are convenient for non-destructive evaluation of plate-like structures since they can generate, without the need for contact with the medium under test, different types of ultrasonic guided waves. Guided-wave EMATs usually generate waves omnidirectionally or in a principal propagation direction. Beam steering is desirable in several applications, such as in inspections of large-area structures. This is usually achieved with several independently controlled elements forming a phased array. Alternatively, mono-element transducers with directional-dependent spectral content can steer the generated wave beam by altering the frequency of the excitation signal. A piezoelectric transducer with this characteristic, namely a frequency steerable acoustic transducer, was previously proposed. Its design was addressed in the wavenumber domain, leading to unconventional transducer shapes, but still reproducible with a piezoelectric patch, albeit unfeasible to implement as an EMAT. Here, we propose a new kind of EMAT, namely, frequency steerable EMAT (FSEMAT), whose design is addressed in the spatial domain in order to ensure its physical realization with a coil-magnet arrangement whilst still effectively presenting steering capability. The novel EMAT was designed to generate the A
0 Lamb wave mode in a frequency range from approximately 100 to 600 kHz. The FSEMAT was fabricated and experimentally evaluated in an aluminium plate at different frequencies within the designed frequency range, where each frequency corresponded to a specific propagating direction with high directivity, assessed by half-power beam widths of approximately 10 degrees. Furthermore, its theoretical directivity was computed by means of a wavenumber spectrum-based model, and showed good agreement with experimental results. The new transducer allows great flexibility effectively providing beam steering with a single EMAT.
Comment on ‘Reversible superconducting-normal phase transition in a magnetic field: the energy-momentum balance including the velocity field of the Berry connection from many-body wave functions’ (2024, Physica Scripta, 99, 015952)
Authors: Nikulov A V 
Published: September 2024

Abstract
According to the article by Hiroyasu Koizumi (2024 Physica Scripta 99 015952) not only Joule heat, but also latent heat should be absent during the superconducting-normal transition in the presence of the magnetic field H = H

c
(T). The publication of the false theory became possible because the author of this theory does not know that the transition at H = H

c
(T) is considered as the first-order phase transition after 1933. The theory, alternative to the conventional BCS theory of superconductivity, was provoked by Hirsch’s publications and the author’s false understanding of the results of calorimetric experiments. The alternative theory contradicts to the law of energy conservation since its author does not know about the work performed during the transition at H = H

c
(T).
Exploring the physical properties of Mn2VSi and Mn2VGe Heusler alloys under high pressure conditions: a theoretical investigation using GGA and TB-mBJ calculation
Authors: Kanwal Shamsa , Jamil M Imran , Tariq Saad , Ahmed Afaq , Adawi Hind , Al Bahir Areej , Ullah Saeed , Munir H Bushra , Ghani Muhammad Usman 
Published: September 2024

Abstract
The investigation into Mn2VSi and Mn2VGe Heusler alloys has yielded crucial insights into their structural, mechanical, thermal, electronic, and magnetic attributes. Employing Density Functional Theory (DFT) with Generalized Gradient Approximation (GGA) and Tran Blaha modified Becke Johnson (TB-mBJ) method, these alloys were comprehensively analyzed. Structurally, both compounds exhibited stability in the regular Heusler structure, with precise lattice constants and pressure-volume variations. Elastic properties indicated mechanical stability and ductile behavior, with enhanced material strength under elevated pressure. Thermodynamic assessments revealed behavior under extreme conditions, while electronic properties showed half-metallic behavior and semiconducting characteristics. Magnetic moments decreased with pressure, signaling a magnetic transition state in alloys. This theoretical study provides valuable insights into Mn2VSi and Mn2VGe compounds, offering potential applications in spintronics and magnetic sensors.
Plasmonic effect of gold nanoparticles on rear side of flexible black silicon wafer fabricated by aluminum-assisted chemical etching
Authors: Omar Halo Dalshad , Uddin Shahnawaz , Braim Farhank Saber , Hashim Md Roslan , Pakhuruddin Mohd Zamir 
Published: September 2024

Abstract
In this work, we investigate the effects of the different sizes of gold (Au) plasmonic nanoparticles (NPs) on the rear surface of flexible black silicon (b-Si) wafer. The flexible b-Si (65 μm thickness) is fabricated by aluminum-assisted chemical etching (AACE) process, utilizing aluminum (Al) as the catalyst. After the b-Si fabrication, nanopores are produced on the flexible wafer surface. Then, gold nanoparticles (Au NPs) are spin-coated on the rear side of the flexible b-Si, followed by surface morphological and optical characterizations. The Au NPs with sizes of 24–92 nm have been deposited on the rear surface of the b-Si wafer. Based on the optical characterization, light absorbance increases above wavelength 800 nm due to enhanced light scattering by the Au NPs at the back surface. The average reflectance (Rave) is calculated in the 300 nm–1100 nm wavelength range for flexible crystalline silicon (c-Si) reference and compared with flexible b-Si surface and flexible b-Si/Au NPs. The lowest Rave of 15.4% is achieved for Au NPs with average size of 92 nm.
A novel numerical method to solve fractional ordinary differential equations with proportional Caputo derivatives
Authors: Mahatekar Yogita M , Kumar Pushpendra 
Published: September 2024

Abstract
In this paper, we develop a novel numerical scheme, namely ‘NPCM-PCDE,’ to integrate fractional ordinary differential equations with proportional Caputo derivatives of the type
pc

D

α

u(t) = f
1(t, u(t)), t ≥ 0, 0 < α < 1 involving a non-linear operator f
1. A new method is developed using a natural discretization of the proportional Caputo derivative and the decomposition method to decompose the non-linear operator f
1. The error and stability analyses for the proposed method are provided. Some illustrated examples are given to compare the solution curves graphically with the exact solution and to prove the utility and efficiency of the method. The proposed NPCM-PCDE is found to be efficient, easy to implement, convergent, and stable.
Understanding the relationship between electric dipole polarizability and photonuclear (-2) moment in odd-A actinide nuclei
Authors: Kemah E , Yakut H , Tabar E , Hoşgör G 
Published: September 2024

Abstract
The nuclear electric dipole (E1) polarizability (α

E1) is mainly dominated by the dynamics of the giant dipole resonance (GDR). α

E1 is proportional to the (-2) moment of the total photo nuclear cross-section (σ
−2). This research investigates the relationship between α

E1 and σ
−2, along with the effects of the Pygmy Dipole Resonance (PDR) and GDR in odd-mass actinide nuclei. For the first time, α

E1 and σ
−2 values have been calculated using the Translational and Galilean Invariant Quasiparticle Phonon Nuclear Model (TGI-QPNM) approach for odd-A actinide nuclei. According to TGI-QPNM results, E1 dipole transitions in the GDR region significantly contribute to σ
−2 due to the energy weighting factor. Below the neutron separation threshold, the PDR in neutron-rich nuclei shows a contribution of about 5% to σ
−2 values. In this region, E1 polarizability can reach values of 20%–25%. The α

E1 values indicate the presence of PDR in these nuclei. Additionally, the Adaptive Neuro-Fuzzy Inference System (ANFIS), a new machine learning method, has been performed to analyze the relationship between α

E1 and σ
−2. The ANFIS results have been compared with those from the TGI-QPNM and experimental data. The TGI-QPNM model achieves an R2 of 0.85–0.95, while the ANFIS model achieves an R2 of 0.99. Moreover, the study suggests that the ANFIS model, consistent with TGI-QPNM results, could be an effective tool for estimating σ
−2 in odd-A actinide nuclei.
A front-fixing numerical method for a fluvio-deltaic sedimentation process with thespace fractional derivative and variable sediment flux
Authors: Joshi Jaya , Rajeev  , Gómez-Aguilar J F , Lavín-Delgado J E 
Published: September 2024

Abstract
This paper centers around a space-fractional mathematical model for a fluvio-deltaic sedimentation process which involves a space-fractional derivative (Caputo derivative) and time dependent variable sediment flux to investigates the movement of shoreline in a sedimentary ocean basin. This model is a specific case of a basic shoreline model and analogous to a Stefan problem. The numerical solution to the problem is acquired by employing a front-fixing explicit finite difference method. The consistency, stability and convergence of the numerical scheme are theoretically analyzed. The effects of variable sediment flux on the movement of shoreline position and the height of sediments are also assessed for different cases.
Quantum transport of topological surface states in presence of circular n-p junctions
Authors: Agrawal Neetu 
Published: September 2024

Abstract
The surface states of topological insulators are characterized by spin-momentum locking, where the electron spin is locked perpendicular to its momentum. This property is preserved under gate potentials which can be used to manipulate spin currents without an external magnetic field enhancing the prospects for spintronic applications. Here, we investigate the scattering of the wave functions of topological surface states within the circular n-p junction positioned on the upper surface of the quintuple-layered three-dimensional topological insulator. With the analytical calculations we explain the scattering of these surface states in such systems.
Correcting the effect of temperature changes in the measurement results of dielectric response in power transformers as an arrhenius type dielectric with the help of artificial neural network
Authors: Mousavi Seyed Amidedin , Bigdeli Mehdi , Arfaei Masoud , Mohamadi Hossein 
Published: September 2024

Abstract
Polarization and Depolarization Current (PDC) and Frequency Domain Spectroscopy (FDS) measurements are common dielectric response tests in time and frequency domain that are widely used to diagnosis insulation status in power transformer companies. Numerous factors affect the PDC and FDS test results, which the most important of them is temperature variation. To accurately interpret the results of the dielectric response, the effect of temperature on the results in time and frequency domains, must be corrected. In this paper, firstly a 200 MVA transformer is selected as a test object and FDS and PDC tests are performed on it at different temperatures. Then, based on the FDS results performed on a transformer at different temperatures, the parameters of the insulation model have been estimated by using genetic algorithm (GA). Next, with the help of artificial neural network (ANN), the parameters of the insulation model, related to the different temperatures are transferred into the reference parameters. After that, the parameters of the transferred insulation model, the FDS curves are plotted and transferred to the reference temperature curve and the effect of temperature on them is compensated. By using the correlation of the time and frequency domain results, with the help of transferred insulation model parameters, the PDC results are also plotted and transmitted on the reference PDC curve. Finally, with such a method, the effect of temperature on the PDC results is compensated.
Gravitational wave signatures of cogenesis from a burdened PBH
Authors: Barman Basabendu , Haque Md Riajul , Zapata Óscar 
Published: September 2024

AbstractWe explore the possibility of explaining the observed dark matter (DM) relic abundance, along with matter-antimatter asymmetry, entirely from the evaporation of primordial black holes (PBH) beyond the semi-classical approximation. We find that, depending on the timing of modification to the semi-classical approximation and the efficiency of the backreaction, it is possible to produce the correct DM abundance for PBHs with masses ≳𝒪(103) g, whereas producing the right amount of baryon asymmetry requires light PBHs with masses ≲𝒪(103) g, satisfying bounds on the PBH mass from the Cosmic Microwave Background and Big Bang Nucleosynthesis. However, in a simplistic scenario, achieving bothsimultaneouslyis not feasible, typically because of the stringent Lyman-αconstraint on warm dark matter mass. In addition to DM and baryon asymmetry, we also investigate the impact of memory burden on dark radiation, evaporated from PBH, constrained by the effective number of relativistic degrees of freedom ΔNeff. Furthermore, we demonstrate how induced gravitational waves from PBH density fluctuations can provide a window to test the memory-burden effects, thereby placing constraints on either the DM mass scale or the scale of leptogenesis.
Assessment of the status of PM2.5 and ground-level O3 pollution variations and meteorological factor effects: A case study in Long An Province, Vietnam
Authors: Hoang Nguyen Phong , Chau My Nguyen Duyen , Ta Bui Long 
Published: September 2024

Abstract
Long An Province has a favorable geographical position in socio-economic development exchanges and is a fundamental bridge between the area of Ho Chi Minh City (HCMC) and the Southeast localities with the Southwestern provinces. Along with the master plan for socio-economic development with a vision for 2030, the province’s air quality issues, especially PM2.5 and surface O3 pollution, will be complex and pose many challenges to effective air pollution management and control. This study aims to investigate the effects of major meteorological characteristics (temperature–T, relative humidity–RH, surface pressure–P, and wind speed–WS) on temporal changes in the correlation between PM2.5 and surface O3 concentrations in Long An province in the 2018-2020 period (computed by a system of coupled WRF/CMAQ models) through trend evaluation using by Mann-Kendall (MK) Test and Theil-Sen Slope, and Pearson correlation analysis. The study results reported that in terms of temporal variations, both value levels of PM2.5 and O3 in the dry season tended to surpass that in the rainy season. Moreover, PM2.5 levels tended to exceed the 24-hour mean threshold (between 1.001 and 3.14 times) and the annual mean threshold (from 1.81 to 2.03 times) of the Vietnamese National Ambient Air Quality Standard. Based on the Pearson correlation analysis, significant influences of meteorological conditions on the pollution status of PM2.5 and surface O3 were also demonstrated, such as the different positive and negative correlations of each meteorological factor on concentration. These outstanding results serve as an essential reference for developing air quality targets and proposing future air pollutant control measures in Long An Province.
IHST (Integrated, Holistic, Spatial, and Thematic) Flood Management Model: The Integration of Flood Model, Green Infrastructure and Non-Structural Mitigation in the Urban Area of Barabai City
Authors: Tri Rendra Graha Dimas , Yudono Adipandang , Afrianto Firman 
Published: September 2024

Abstract
The January 2021 Floods paralyzed the entire Hulu Sungai Tengah Region, South Kalimantan Province, Indonesia, submerging 20,553 houses, causing minor damage to 2,973 houses, severe damage to 268 houses, and resulting in losses exceeding 53 million dollars. The Barabai Urban Area was one of the locations severely affected by flood. The flood management was conducted in the Barabai urban area to predict and visualize water movement during flooding, aiding in understanding and mitigating flood risks, as well as developing effective flood management strategies. The flood management was carried out adopted the IHST Model, which is the abbreviation from Integrated, Holistic, Spatial, and Thematic. The activities involve HECRAS 6.2 application, utilizing Google Earth terrain data, river geometry data, and flood discharge analysis based on the Nakayasu method. The analysis results highlighted the need for both structural and non-structural flood interventions. Non-structural interventions aiming to reduce vulnerability and enhance community capacity in facing flood. Structural developments involved the construction of storm water retention ponds and river embankments at specific locations based on the flood modelling results. The concept of polder and river embankment development was approached through green infrastructure principles, as flood management solutions should not only facilitate rapid water drainage but also improve soil absorption to prevent prolonged inundation.
Multidimensional dynamic control of optical skyrmions in graphene–chiral–graphene multilayers
Authors: Zhu Shuo , Lei Xinrui , Shen Xi , Hu Haifeng , Zhang Ni , Zhan Qiwen 
Published: September 2024

Abstract
Optical skyrmions are topological quasiparticles with a complex vectorial field structure. Their associated characteristics of ultra-small, ultra-fast and topological protection have great application prospects in high density data storage, light matter interaction and optical communication. At present, the research of optical skyrmions is still in its infancy, where the construction and flexible regulation of different topological textures are current research hotspot. Here, we combine the twist degree of freedom of materials and optical skyrmions. Based on graphene–chiral–graphene multilayers structure, we demonstrate the field mode symmetry and hybridization to form Bloch-type graphene plasmons skyrmion lattice. At the same time, by changing chirality parameter, the Fermi energy of graphene and the phase of incident light, multidimensional control of Bloch-type optical skyrmions can be realized. Our work demonstrated that the properties of materials provide the additional dimensions to regulate the topological states, and the combination of different materials structures provides the possibility for dynamic construction and manipulation of multiple topological states, which is expected to find applications in integrated nanophotonics devices.
Effect of promoters on the performance of CuNi catalysts for hydrogen production from methanol decomposition
Authors: Zhang Beidong , Jiang Yankun , Cong Le , Chen Yexin , Chen Lunhong , Yang Zhengdong 
Published: September 2024

Abstract
Utilizing the exhaust heat from engines to decompose methanol for hydrogen production, and subsequently introducing this hydrogen into the combustion chamber, is one of the crucial approaches for achieving energy savings and emission reductions. The role of an efficient and stable catalyst for methanol decomposition is paramount in this application. Therefore, CuNi-based catalysts modified with promoters such as Zr, La, Mn, and Mg were prepared using a stepwise impregnation method. The developed catalysts were tested using various analytical methods and characterization techniques. The results indicate that the addition of the Zr enhances the dispersion of active components, improves the catalyst’s reducibility. This, in turn, enhances the catalyst’s activity and hydrogen selectivity. The hydrogen yield of the Zr modified catalyst increased by an average of 12% compared to the original catalyst. Furthermore, the Zr modified catalyst exhibits exceptional stability after prolonged use. La can enhance the low-temperature activity of the catalyst but performs poorly at high temperatures. The promoter Mn has a minimal impact on the overall performance of the catalyst. Conversely, the addition of Mg as a promoter inhibits the dispersion of active components, resulting in adverse effects on the catalyst.
Effect of laser welding parameters on the microstructure and tensile properties of low-alloy high-strength steel
Authors: Li Weiji , Feng Aixin , Wang Yu , Wang Jun 
Published: September 2024

Abstract
The studying employed orthogonal experimental approach to optimize the laser welding process parameters for HC420LA low-alloy high-strength steel. Through metallographic analysis, microhardness testing, and tensile testing, the study assessed and contrasted the properties of laser-welded and arc-welded joints. The findings revealed that the most optimal laser welding conditions were 1.8 kW laser power, 2.5 m min−1 welding speed, and a focus distance of 1.5 mm, resulting in a well-formed ‘X’ shaped weld bead. Comparative analysis demonstrated that the laser-welded joint exhibited a finer microstructure, primarily composed of bainite and ferrite, whereas the arc-welded joint consisted of ferrite and martensite. Notably, the laser-welded joint exhibited superior mechanical properties, including increased microhardness and tensile strength, underscoring the distinct advantage of laser welding technology in high-strength steel welding, particularly in enhancing the weld joint’s quality and performance.