Results in Physics最新文献

{"title":"The anisotropy of molybdenite planes: Analysis based on the adsorption behaviors of reagent and H2O","authors":"","doi":"10.1016/j.rinp.2024.107996","DOIUrl":"10.1016/j.rinp.2024.107996","url":null,"abstract":"<div><div>Multiple planes with different properties are exposed after the comminution of molybdenite because of the anisotropy of molybdenite. Study on the properties of different planes is of great significance to enhance the comprehensive utilization of molybdenite, especially in flotation. In order to explore the properties of different planes, the two main planes of molybdenite (basal plane and edge plane) are respectively taken as the research object in this paper, and the properties of planes are expressed using DFT through the adsorption behaviors of a new reagent named DTC-CTS and water molecules. The results show that edge plane has higher activity than basal plane. This is because there are exposed molybdenum atoms on the edge plane, and the sulfur atoms in DTC-CTS and oxygen atoms in water molecules are easy to react with the exposed molybdenum atoms. While the activity of basal plane is low because of the hinderance effect of sulfur atoms in the skin layer. The different adsorption behaviors of water molecules on molybdenite planes verified the hydrophobicity of different planes. In addition, the results also show that the water can affect the DTC-CTS adsorption on edge plane. Water can enhance interaction between single-bond sulfur atom and molybdenum atom, and weaken the interaction between double-bond sulfur atom and molybdenum atom on edge plane.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358819","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":"Modified Holling Tanner diffusive and non-diffusive predator–prey models: The impact of prey refuge and fear effect","authors":"","doi":"10.1016/j.rinp.2024.107995","DOIUrl":"10.1016/j.rinp.2024.107995","url":null,"abstract":"<div><div>The secondary consequences of predator species on prey species have substantial implications for population dynamics. A deeper comprehension of the dynamics between prey and predator can be achieved through the examination of indirect consequences. This work examines the dynamic behavior of a modified Holling-Tanner model. The interactions between the species are characterized by a functional response of the Beddington–DeAngelis type. Factors such as prey refuge, fear factor, disturbance intensity, and cross diffusion have been taken into account. The boundedness, feasibility of equilibrium points, their stability and restrictions for Hopf bifurcation of non-spatial model system are derived. The study explores the combined effects of prey refuge presence and fear factors on population dynamics. Furthermore, the investigation focuses on the stability of spatial self-diffusion and cross-diffusion model systems, as well as the specific conditions that lead to Turing instability. Ultimately, it has been shown that in the context of self-diffusion, a moderate level of fear promotes the survival of prey, whereas an excessive level of dread hinders the survival of prey. Concurrently, the mean density of prey exhibited a gradual decline as the refuge parameters increased. The spatial patterns of the population have also been investigated. As the mutual interference between prey populations intensifies, the spatial distribution of the prey population transitions from a clustered pattern to a combination of striped and clustered patterns, ultimately settling into a striped pattern. With the gradual growth of the half saturation constant, the prey population reached a state of uniform distribution. In the scenario of cross diffusion, when the prey is heavily impacted by the pursuit of predators, the fear effect, when appropriately used, did not have a significant impact on the survival of the prey. This work adds to the existing body of knowledge by revealing novel insights into the influence of indirect factors on the behavior of predator and prey populations.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142358733","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":"International Advisory Board","authors":"","doi":"10.1016/S2211-3797(24)00697-1","DOIUrl":"10.1016/S2211-3797(24)00697-1","url":null,"abstract":"","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438203","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":"Diverse soliton wave profile assessment to the fractional order nonlinear Landau-Ginzburg-Higgs and coupled Boussinesq-Burger equations","authors":"","doi":"10.1016/j.rinp.2024.107994","DOIUrl":"10.1016/j.rinp.2024.107994","url":null,"abstract":"<div><div>The space–time fractional Landau-Ginzburg-Higgs equation and coupled Boussinesq-Burger equation describe the behavior of nonlinear waves in the tropical and mid-latitude troposphere, exhibiting weak scattering, extended connections, arising from the interactions between equatorial and mid-latitude Rossby waves, fluid flow in dynamic systems, and depicting wave propagation in shallow water. The improved Bernoulli sub-equation function method has been used to achieve new and wide-ranging closed-form solitary wave solutions to the mentioned nonlinear fractional partial differential equations through beta-derivative. A wave transformation is applied to renovate the fractional-order equation into an ordinary differential equation. Some standard wave shapes of multiple soliton type, single soliton, kink shape, double soliton shape type, triple soliton shape, anti-kink shape, and other types of solitons have been established. The more updated software Python is used to display the solutions by using 3D and contour plotlines to describe the physical significances of attained solutions more clearly. The findings of this study are straightforward, adaptable, and quicker to simulate. It has been notable that the improved Bernoulli sub-equation function method is practical, effective, and offers more sophisticated solutions that can help to<!--> <!-->generate a large number of wave solutions for various models.</div></div>","PeriodicalId":21042,"journal":{"name":"Results in Physics","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142423712","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":"Plastic deformations in NiCoFe medium-entropy alloy investigated using nanoindentation simulations","authors":"","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":null,"pages":null},"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":"","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":null,"pages":null},"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":"","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":null,"pages":null},"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":"","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":null,"pages":null},"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":"Experimental demonstration of bi-directional laser ranging and data communication for space gravitational wave detection","authors":"","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":null,"pages":null},"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":"Interpretable machine learning methods to predict the mechanical properties of ABX3 perovskites","authors":"","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":null,"pages":null},"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}