Results in Physics最新文献

{"title":"Plastic deformations in NiCoFe medium-entropy alloy investigated using nanoindentation simulations","authors":"Qinqin Xu ,&nbsp;F. Javier Domı́nguez-Gutiérrez ,&nbsp;Wenyi Huo ,&nbsp;Stefanos Papanikolaou","doi":"10.1016/j.rinp.2024.107989","DOIUrl":"10.1016/j.rinp.2024.107989","url":null,"abstract":"<div><div>Medium-entropy alloys (MEA) have potential load-bearing applications as high-performance structural materials. In this work, the plastic deformations in NiCoFe MEAs were investigated using nanoindentation atomistic simulations. The nanoindentation responses of three typical orientations of NiCoFe single-crystals were investigated, i.e., [001], [011] and [111]. The results show that, during nanoindentation, Shockley partials on (111) slip planes remarkably affect dislocation-related activities including nucleation, gliding, and interactions. The form of atomic pile-ups is highly non-uniform and strongly asymmetrical due to the presence of multi-principal elements. The dislocation nucleation mechanism of the alloys during nanoindentation is proposed in detail. We find evidence that a hexagonal close-packed phase is formed from the face-centered cubic structure during nanoindentation.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107989"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A data-driven model for the field emission from broad-area electrodes","authors":"Moein Borghei,&nbsp;Robin Langtry","doi":"10.1016/j.rinp.2024.107999","DOIUrl":"10.1016/j.rinp.2024.107999","url":null,"abstract":"<div><div>Electron emission from cathodes in high field gradients is a quantum tunneling effect. The 1928 Fowler–Nordheim field emission (FE) equation and the 1956 Murphy–Good FE equation have traditionally been key in describing cold field emissions, offering estimates for emitters for almost a century. Nevertheless, applying FE theory in practice is often constrained by the lack of data on the distribution and geometry of the emission sites. Predictions become more challenging with an uneven electric field distribution at the cathode surface. Consequently, FE formulations are frequently calibrated using current–voltage data after test, limiting their efficacy as true predictive models.</div><div>This study develops an alternative model for field emission using a data-driven predictive approach based on (1) vast experimental data, (2) electrostatic simulations of the cathode surface, and (3) detailed material and geometry properties, which together overcome these limitations. The objective of this work is to develop and harness this comprehensive dataset to train a machine learning model capable of providing precise predictions of the cathode current in order to further the understanding and application of field emission phenomena. More than 259 h of experimental data have been processed to train and benchmark some of the well-known machine learning models. After two stages of optimization, a coefficient of determination <span><math><mrow><mo>&gt;</mo><mn>98</mn><mtext>%</mtext></mrow></math></span> is achieved in the prediction total field emission current using ensemble models.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"66 ","pages":"Article 107999"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficiency tunable terahertz graphene metasurfaces for reflective single/dual-focusing effects based on Pancharatnam-Berry phase","authors":"Wenzhi Yang ,&nbsp;Lingling Yang ,&nbsp;Bin Cai ,&nbsp;Ling Wu ,&nbsp;Siqi Feng ,&nbsp;Yongzhi Cheng ,&nbsp;Fu Chen ,&nbsp;Hui Luo ,&nbsp;Xiangcheng Li","doi":"10.1016/j.rinp.2024.108003","DOIUrl":"10.1016/j.rinp.2024.108003","url":null,"abstract":"<div><div>In this paper, an efficiency tunable reflective metasurface (MS) consisting of a dielectric substrate sandwiched between hollow Z-shaped (HZS) structure graphene and a metallic ground plane is proposed for single/dual-focusing effects based on Pancharatnam-Berry (PB) in terahertz (THz) region. Numerical simulations demonstrate that the designed HZS graphene can achieve a circular polarization (CP) conversion with efficiency of approximately 98 % at a Fermi energy level (<em>E_F</em>) of 1.0 eV. Moreover, by adjusting the rotation angle of the HZS graphene, a full 0-2π phase coverage can be achieved. Of note, the simulation results also reveal that the reflective CP conversion efficiency is highly dependent on the value of the <em>E_F</em>. By carefully designing the spatial phase distribution of the graphene MS, tunable reflective single/dual-focusing effects can be realized, with focusing efficiency controlled by the <em>E_F</em>. It is anticipated that the proposed tunable graphene MS will have broad applications in communications, imaging, and others in THz domains.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 108003"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical analysis of unsteady free convection of Al2O3 inside a tubular reactor under the influences of exothermic reaction, and inclined MHD as an application to chemical reactor","authors":"Hussein H. Alaydamee ,&nbsp;Mohammed Azeez Alomari ,&nbsp;Qusay H. Al-Salami ,&nbsp;Farah Q.A. Alyousuf ,&nbsp;Faris Alqurashi ,&nbsp;Mujtaba A. Flayyih","doi":"10.1016/j.rinp.2024.107993","DOIUrl":"10.1016/j.rinp.2024.107993","url":null,"abstract":"<div><div>This paper delves into the numerical investigation of aluminum oxide–water nanofluid thermal and dynamic performances under the influences of magnetic field application and chemical reaction, utilizing the Finite Element Method within a circular enclosure containing three inner tubes, as an application to the heat exchanging phenomenon between the reactive shell of the cavity and the surface of the triple tubes. Various governing parameters were studied for their interaction on the nanofluid flow and heat transmission rate within the proposed geometry, including the Rayleigh parameter (<span><math><mrow><msup><mrow><mn>10</mn></mrow><mn>3</mn></msup><mo>≤</mo><mi>R</mi><mi>a</mi><mo>≤</mo><msup><mrow><mn>10</mn></mrow><mn>5</mn></msup></mrow></math></span>), Hartmann parameter (<span><math><mrow><mn>0</mn><mo>≤</mo><mi>H</mi><mi>a</mi><mo>≤</mo><mn>61</mn></mrow></math></span>), nanoparticles concentration (<span><math><mrow><mn>0</mn><mo>≤</mo><mi>∅</mi><mo>≤</mo><mn>6</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>-</mo><mn>2</mn></mrow></msup></mrow></math></span>), magnetic rotational angle (<span><math><mrow><msup><mrow><mn>0</mn></mrow><mi>o</mi></msup><mo>≤</mo><mi>γ</mi><mo>≤</mo><msup><mrow><mn>90</mn></mrow><mi>o</mi></msup></mrow></math></span>), and Frank-Kamenetskii parameter (<span><math><mrow><mn>0</mn><mo>≤</mo><msub><mi>F</mi><mi>k</mi></msub><mo>≤</mo><mn>3</mn></mrow></math></span>). The results indicated that raising Ra from 10³ to 10⁵ results in expediting the nanofluid velocity by 10.62 % and 100 % respectively as well as raising the total heat transfer efficiency. The nanofluid speed was also increased by 28.57 % when F_k has to further increase to a value of 3. When there was no exothermic activity present, the rate of heat transmission was at its lowest, and it was greater when the F_k value was 3. Similarly, there were discernible impacts in various areas of the geometry as the Ha number intensified and the Nu_avg decreased. Improvements in local and mean Nusselt parameters are observed when the concentration of nanoparticles is increased, suggesting better heat transfer, achieving an increase by 7 % in the average Nusselt number. This research emphasizes the importance of nanoparticle concentration in raising the medium’s rates of heat transmission, contributing to advancements in energy storage development.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107993"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interpretable machine learning methods to predict the mechanical properties of ABX3 perovskites","authors":"S.B. Akinpelu ,&nbsp;S.A. Abolade ,&nbsp;E. Okafor ,&nbsp;D.O. Obada ,&nbsp;A.M. Ukpong ,&nbsp;S. Kumar R. ,&nbsp;J. Healy ,&nbsp;A. Akande","doi":"10.1016/j.rinp.2024.107978","DOIUrl":"10.1016/j.rinp.2024.107978","url":null,"abstract":"<div><div>This paper proposes the utility of interpretable ensemble learning models for predicting the mechanical properties (bulk, shear and Young moduli) of ABX₃ perovskite compounds with the A, B, and X referring to the 3 elements that make the cubic 3-dimensional framework of the perovskite compounds. These models consist of 3 ensemble learning techniques namely CatBoost, Random Forest, and XGBoost. To expand the feature space, robust first-principles density functional theory calculations were used to generate some of the input features, namely elastic constants, density, volume per atom, and ground state energy per atom. The order of the input feature ranking that influences the machine learning (ML) model decisions was then determined. For this, we performed correlation analysis on the multi-dimensional input feature space, suppressed features with high collinearity, and selected features with limited correlation. We trained the three ensemble learning techniques on the desired vectorial input feature representation to predict the mechanical properties. Furthermore, we employed the Shapley Additive Explanations (SHAP) algorithm for analysing the intrinsic decision-making rationality of the ensemble learning models. We measured the performance in the context of the error metrics and coefficient of determination, R². The results show that XGBoost outperforms other approaches when predicting the shear modulus or Young modulus of the perovskite compounds yielding the least error metrics and the highest R² value (0.97) in the testing phase. However, both CatBoost and Random Forest outperformed XGBoost when attempting to predict the bulk modulus in the testing phase. The deficiency of the XGBoost in predicting the bulk modulus can be ascribed to an overfitting problem which can occur when the ML model gives accurate predictions for training data but not for test data. Furthermore, the SHAP algorithm provides an insight into the order of feature importance (from highest to lowest). Additionally, we conducted a post-analysis using a holistic ranking to analyse the relative importance of the SHAP feature impact comprehension for the examined ensemble learning techniques. Our findings indicate that the elastic constants are the most important input features influencing the predictive decision of the ensemble learning models.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107978"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental demonstration of bi-directional laser ranging and data communication for space gravitational wave detection","authors":"Peiquan Chen ,&nbsp;Yibin Zhang ,&nbsp;Rujie Deng ,&nbsp;Heshan Liu ,&nbsp;Ziren Luo","doi":"10.1016/j.rinp.2024.107985","DOIUrl":"10.1016/j.rinp.2024.107985","url":null,"abstract":"<div><div>In this study, we designed ranging parameters and refined a loop filtering algorithm to solve the problem of parameter compatibility with the phasemeter and low ranging accuracy under bidirectional communication conditions. This enables the ranging and communication system to be integrated directly into the phasemeter as an auxiliary module. Experimental results compare fiber measurement lengths under different clock sources, indicating that the system achieves an ranging accuracy of 82.1 cm with an rms error of 9.14 cm. Additionally, the data communication rate reaches 19.5 kbps with a bit error rate below <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup></mrow></math></span>, all while ensuring that the implementation of the laser ranging and data communication system utilizes only 1% of the optical power to avoid introducing excessive phase noise to the scientific interferometer.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107985"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Investigation of structural and physical properties of Eu3+ ions substituted Ni0.4Cu0.2Zn0.4Fe2O4 spinel ferrite nanoparticles prepared via sonochemical approach” [Res. Phys. 17 (2020) 103061]","authors":"Y. Slimani ,&nbsp;B. Unal ,&nbsp;M.A. Almessiere ,&nbsp;A. Demir Korkmaz ,&nbsp;Sagar E. Shirsath ,&nbsp;Ghulam Yasin ,&nbsp;A.V. Trukhanov ,&nbsp;A. Baykal","doi":"10.1016/j.rinp.2024.107981","DOIUrl":"10.1016/j.rinp.2024.107981","url":null,"abstract":"","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107981"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancement of high-frequency harmonics in resonators using multilayered structures with polarity-inverted layers","authors":"Natalya F. Naumenko","doi":"10.1016/j.rinp.2024.107998","DOIUrl":"10.1016/j.rinp.2024.107998","url":null,"abstract":"<div><div>Periodically Poled Piezoelectric Film (P3F) stacks have recently been reported as a promising platform for next-generation radio-frequency acoustic filters that extend into cm- and mm-wave bands. By demonstrating the potential for developing high-performance acoustic devices with frequencies up to 20 GHz, P3F structures based on lithium niobate (LiNbO3) films have opened up new possibilities. In this study, the influence of key parameters such as the number of layers, crystal orientation, duty factor, and variation in thicknesses between the layers on the efficiency of the n-th harmonic excitation and spurious modes was examined. To enhance higher-order harmonics, which are suppressed in P3F structures, a novel multilayered stack with Aperiodically Polarized Piezoelectric Films (APPF) is proposed. Optimizing the ratio between layer thicknesses can enhance higher-order harmonics. An optimization principle is described and illustrated by examples of three-layered APPF structures optimized for the generation of antisymmetric Lamb wave harmonics A3-A17, with electromechanical coupling continuously decreasing with frequency. High-frequency modes excited in APPF structures fill the gaps in frequencies and electromechanical coupling coefficients between the modes generated in P3F stacks and can provide greater diversity of device performance.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107998"},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lie symmetry analysis, traveling wave solutions and conservation laws of a Zabolotskaya-Khokholov dynamical model in plasma physics","authors":"Naseem Abbas ,&nbsp;Akhtar Hussain ,&nbsp;Shah Muhammad ,&nbsp;Mohammad Shuaib ,&nbsp;Jorge Herrera","doi":"10.1016/j.rinp.2024.107986","DOIUrl":"10.1016/j.rinp.2024.107986","url":null,"abstract":"<div><div>This article analyzes the analytic and solitary wave solutions of the one-dimensional Zabolotskaya-Khokholov (ZK) dynamical model which provides information about the propagation of sound beam or confined wave beam in nonlinear media and studies of beam deformation. By the Lie symmetry analysis method, we acquire the vector fields, commutation relations, optimal system, reduction, and analytic solutions to the specified equation by exerting the Lie group method. Moreover, the solitary wave solutions of the ZK model are procured by exerting the new auxiliary equation method (NAEM). The behavior of the acquired outcomes for several cases is exhibited graphically through two and three-dimensional dynamical wave profiles. Furthermore, the conservation laws of the ZK model are acquired by Ibragimov’s new conservation theorem.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107986"},"PeriodicalIF":4.4,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in PVP-assisted thermal treatment: Impact on nanostructure properties, potential applications, challenges, and future perspectives","authors":"Naif Mohammed Al-Hada ,&nbsp;Shicai Xu ,&nbsp;A.M. Al-Ghaili ,&nbsp;Bandar Ali Al-Asbahi ,&nbsp;Hussein Baqiah ,&nbsp;Jianlei Yang ,&nbsp;M.N. Azlan ,&nbsp;Qiang Li","doi":"10.1016/j.rinp.2024.107990","DOIUrl":"10.1016/j.rinp.2024.107990","url":null,"abstract":"<div><div>Nanotechnology has garnered significant attention for its wide-ranging applications in biomedicine, energy, and environmental science. The synthesis of nanomaterials with specific properties is crucial for advancing these fields. Among various methods, thermal treatment has emerged as a promising technique for producing diverse nanostructures. However, thermal treatment alone often leads to larger particle sizes and poor uniformity, limiting the practical applications of the resulting nanomaterials. Incorporating polyvinylpyrrolidone (PVP) as a capping agent addresses these challenges by reducing particle size and enhancing uniformity. Optimizing parameters such as PVP concentration, molecular weight, temperature, and precursor ratios is key to improving the performance of the PVP-assisted thermal treatment method. This paper reviews recent progress in synthesizing nanostructures using PVP-assisted thermal treatment, including key characterization techniques. It also examines the applications of these nanostructures in fields such as biomedicine, energy, and environmental science. The review identifies challenges in the synthesis and characterization process, while also outlining potential future directions for enhancing this method. The insights provided will be valuable to researchers working in nanotechnology and related disciplines.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":"65 ","pages":"Article 107990"},"PeriodicalIF":4.4,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142322193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}