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Changes in the latencies of visual-evoked potentials in people undergoing tennis training Dynamic comparison before and after 8 weeks training 被引量:3
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作者 Jingguo Zhao Shujuan Pang 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第3期284-287,共4页
BACKGROUND: Some previous studies have shown that exercise is an important factor that affects the latencies of visual-evoked potentials (VEPs). OBJECTIVE: To investigate the effects of spending a period of time u... BACKGROUND: Some previous studies have shown that exercise is an important factor that affects the latencies of visual-evoked potentials (VEPs). OBJECTIVE: To investigate the effects of spending a period of time undergoing tennis training on the latencies of VEPs by comparing the latencies of VEPs before tennis training with those after 8 weeks of tennis training. DESIGN, TIME AND SETTING: The non-randomly concurrent controlled experiment was performed in the Department of Human Movement Sciences, Physical Education College, Shandong Normal University from April to June 2007. PARTICIPANTS: In total, 45 healthy volunteers from Shandong Normal University were selected as subjects, including 31 students majoring in physical education (11 males and 5 females participated in the tennis training plan for 8 weeks), and 14 students from other subjects. Informed consent was obtained. According to whether they were majoring in physical education or not, and whether or not they took part in tennis training, the students were divided into 3 groups: a tennis group of physical education students (n = 16) a non-tennis group of physical education students (n =15) and a non-tennis group of non-physical education students (n = 14). METHODS: The subjects in the tennis group took part in a regular tennis training plan of 2 hours a day and 3 days per week, for 8 weeks, while the subjects in two non-tennis groups were not in the tennis training plan The NDI-200 neural electricity tester (Shanghai Haishen Medical Electronic Instrument Co., Ltd.) was used to measure VEPs before and after the experiment in all three groups, and to compare the latencies of VEPs recorded before training with those recorded after training. MAIN OUTCOME MEASURES: Comparison of the changes in latencies of VEPs before and after 8 weeks of tennis training. RESULTS: All 45 subjects finished the test and datas from all were included in the statistical analysis. There were no significant differences among all the three groups before tennis training, but the female subjects in each group showed significantly shorter N75 latencies than male subjects of the same group (P 〈 0.05). Comparing the latencies of VEPs after training with those recorded before training, the N75, P100 and N145 latencies were all found to be significantly shorter than before training in the tennis group (P 〈 0.05), but the N75, P100 and N145 latencies were unaffected in the two non-tennis groups (P 〉 0.05); some latencies were even significantly longer than the before-training values. CONCLUSION: Special tennis training for 8 weeks can make the subjects' VEP latencies significantly shorter. Thus, VEP latencies can change with tennis training. 展开更多
关键词 visual-evoked potentials TENNIS LATENCY neuro-electrophysiological
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Redefining atomistic simulations of all-solid-state batteries through machine learning interatomic potentials
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作者 Qian Chen Siwen Wang Chen Ling 《Journal of Energy Chemistry》 2026年第1期666-687,I0015,共23页
All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lit... All-solid-state batteries(ASSBs)represent a next-generation energy storage technology,offering enhanced safety,higher energy density,and improved cycling stability compared to conventional liquid-electrolyte-based lithium-ion batteries.Understanding and optimizing the complex chemistries and interfaces that underpin ASSB performance present significant challenges from both experimental and modeling perspectives.In particular,atomistic simulations face difficulties in capturing the complex structure,disorder,and dynamic evolution of materials and interfaces under practically relevant conditions.While established methods such as density functional theory and classical force fields have provided valuable insights,some questions remain difficult to address,particularly those involving large system sizes or long timescales.Recently,machine learning interatomic potentials(MLIPs)have emerged as a transformative tool,enabling atomistic simulations at length and time scales that were previously challenging to access with conventional approaches.By delivering near first-principles accuracy with much greater efficiency,MLIPs open new avenues for large-scale,long-timescale,and high-throughput simulations of solid-state battery materials.In this review,we present a comparative overview of density functional theory,classical force fields,and MLIPs,highlighting their respective strengths and limitations in ASSB research.We then discuss how MLIPs enable simulations that reach longer timescales,larger system sizes,and support high-throughput calculations,providing unique insights into ion transport and interfacial evolution in ASSBs.Finally,we conclude with a summary and outlook on current challenges and future opportunities for expanding MLIP capabilities and accelerating their impact in solid-state battery research. 展开更多
关键词 All-solid-state batteries Solid-state electrolytes Machine-learning interatomic potential Atomistic modeling lon transport INTERFACES
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Visual acuity evaluated by pattern-reversal visual-evoked potential is affected by check size/visual angle 被引量:1
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作者 Xiping Chen Qianqian Li +3 位作者 Xiaoqin Liu Li Yang Wentao Xia Luyang Tao 《Neuroscience Bulletin》 SCIE CAS CSCD 2012年第6期737-745,共9页
Objective To systemically explore the range of visual angles that affect visual acuity, and to establish the relationship between the P 1 component (peak latency -100 ms) of the pattern-reversal visual-evoked potent... Objective To systemically explore the range of visual angles that affect visual acuity, and to establish the relationship between the P 1 component (peak latency -100 ms) of the pattern-reversal visual-evoked potential (PRVEP) and the visual acuity at particular visual angles. Methods Two hundred and ten volunteers were divided into seven groups, according to visual acuity as assessed by the standard logarithmic visual acuity chart (SLD-II). For each group, the PRVEP components were elicited in response to visual angle presentations at 8°, 4°, 2°, 1°/60', 30', 15', and 7.5', in the whiteblack chess-board reversal mode with a contrast level of 100% at a frequency of 2 Hz. Visual stimuli were presented monocularly, and 200 presentations were averaged for each block of trials. The early and stable component P1 was recorded at the mid-line of the occipital region (Oz) and analyzed with SPSS 13.00. Results (1) Oz had the maximum Pl amplitude; there was no significant difference between genders or for interocular comparison in normal controls and subjects with optic myopia. (2) The P1 latency decreased slowly below 30', then increased rapidly. The P1 amplitude initially increased with check size, and was maximal at -1° and -30'. (3) The P1 latency in the group with visual acuity 〈0.2 was signifi- cantly different at 8°, 15' and 7.5', while the amplitude differed at all visual angles, compared with the group with normal vision. Differences in P1 for the groups with 0.5 and 0.6 acuity were only present at visual angles 〈1°. (4) Regression analysis showed that the P1 latency and amplitude were associated with visual acuity over the full range of visual angles. There was a moderate correlation at visual angles 〈30'. Regression equations were calculated for the P1 components and visual acuity, based on visual angle. Conclusion (1) Visual angle should be taken into consideration when exploring the function of the visual pathway, especially visual acuity. A visual angle -60' might be appropriate when using PRVEP com- ponents to evaluate poor vision and to identify malingerers. (2) Increased P1 amplitude and decreased P1 latency were as- sociated with increasing visual acuity, and the P1 components displayed a linear correlation with visual acuity, especially in the range of optimal visual angles. Visual acuity can be deduced from P 1 based on visual angle. 展开更多
关键词 visual acuity visual angle pattern-reversal visual-evoked potential check size regression equation
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REANN 2.0:An Efficient Package of Neural Network Potentials for Multi-Element Systems
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作者 Yixi Zhang Junfan Xia +1 位作者 Yaolong Zhang Bin Jiang 《Chinese Journal of Chemical Physics》 2025年第6期797-806,I0238,共11页
Recursively embedded atom neural network(REANN)is a general-purpose atomistic machine learning software package for representing potential energy and other physical properties.The original REANN 1.0 architecture is a ... Recursively embedded atom neural network(REANN)is a general-purpose atomistic machine learning software package for representing potential energy and other physical properties.The original REANN 1.0 architecture is a physically inspired invariant message passing neural network,which was designed for systems with a limited number of elements.It is efficient but hardly transferable to more complex multi-element systems.In this work,we release REANN 2.0 aimed at multi-element systems and universal potentials,which integrates element embedding and equivariant representation.Compared to the first version,REANN 2.0 demonstrates enhanced ele-ment transferability and higher accuracy across various periodic systems with higher efficiency.Built upon this framework,a pre-trained REANN-MPtrj model without fine-tuning accurately predicts the lithium-ion diffusion dynamics in a benchmark solid-state electrolyte Li_(3)YCl_(6).We hope this open-source software package will facilitate the development of computationally efficient universal potentials in the future. 展开更多
关键词 Machine learning potential Message passing neural network Universal machine learning potential Molecular dynamics
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An in-depth study of spin-and momentum-dependent interaction potentials between two spin-1/2 fermions mediated by light spin-0 particles
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作者 Yang Zhong Zhi-Hui Guo Hai-Qing Zhou 《Communications in Theoretical Physics》 2025年第8期82-93,共12页
We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and co... We present a calculation by including the relativistic and off-shell contributions to the interaction potentials between two spin-1/2 fermions mediated by the exchange of light spin-0 particles,in both momentum and coordinate spaces.Our calculation is based on the four-point Green's function rather than the scattering amplitude.Among the sixteen potential components,eight that vanish in the non-relativistic limit are shown to acquire nonzero relativistic and off-shell corrections.In addition to providing relativistic and off-shell corrections to the operator basis commonly used in the literature,we introduce an alternative operator basis that facilitates the derivation of interaction potentials in the coordinate space.Furthermore,we calculate both the long-range and short-range components of the potentials,which can be useful for future experimental analyses at both macroscopic and atomic scales. 展开更多
关键词 AXION potential relativistic correction
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A comprehensive review of meal replacement from dining table to sickbed:beyond biomedical potentials
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作者 Hao Qiang Tianshu Xu +4 位作者 Peng Ma Siyuan Zhang Guanhua Du Guifen Qiang Tengfei Ji 《Food Science and Human Wellness》 2025年第3期822-834,共13页
The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacem... The emergence of meal replacement(MR)originates from physical exercise or fitness as a substitute for one or all meals and later expands to the field of weight loss.Indeed,the main application of current meal replacement is to lose body weight,whether patients with obesity,diabetes,fatty liver,infertile or pregnant women can benefit from weight loss.In addition,MRs still exhibit more biomedical potential in preventing and treating diseases,like anti-diabetes,improving fatty liver and kidney disease,preventing cancer,conceiving and reducing pregnancy complications,and improving life quality.Indeed,there are also disadvantages to meal replacement,including causing adverse effects,although most are acceptable and tolerated.To date,various commercially-developed MRs are walking from dining table to sickbed.Therefore,a scientific understanding of the advantages and disadvantages of meal replacements is crucial for their extensive application beyond biomedical potentials. 展开更多
关键词 Meal replacement Weight loss Biomedical potentials
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Effective nucleus-nucleus potentials for heavy-ion fusion reactions
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作者 Ning Wang Jin-Ming Chen Min Liu 《Nuclear Science and Techniques》 2025年第2期103-111,共9页
Based on the Skyrme energy density functional and reaction Q-value,this study proposed an effective nucleus-nucleus poten-tial for describing the capture barrier in heavy-ion fusion processes.The 443 extracted barrier... Based on the Skyrme energy density functional and reaction Q-value,this study proposed an effective nucleus-nucleus poten-tial for describing the capture barrier in heavy-ion fusion processes.The 443 extracted barrier heights were well reproduced with a root-mean-square(RMS)error of 1.53 MeV,and the RMS deviations with respect to 144 time-dependent Hartree-Fock capture barrier heights were only 1.05 MeV.Coupled with the Siwek-Wilczyński formula,wherein three parameters were determined by the proposed effective potentials,the measured capture cross sections at energies around the barriers were reasonably well reproduced for several fusion reactions induced by nearly spherical nuclei as well as by nuclei with large deformations,such as^(154)Sm and^(238)U.The shallow capture pockets and small values of the average barrier radii resulted in the reduction of the capture cross sections for 52,54Cr-and 64 Ni-induced reactions,which were related to the synthesis of new super-heavy nuclei. 展开更多
关键词 Nucleus-nucleus potential Fusion reactions Superheavy nuclei Capture cross sections
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Event-related potentials reveal hypnotherapy's impact on attention bias in social anxiety disorder
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作者 Han Zhang Mi Zhang +8 位作者 Ni Li Wen-Zhuo Wei Lin-Xi Yang Yong-Yi Li Zhen-Yue Zu Li-Jun Ma Hui-Xue Wang Kai Wang Xiao-Ming Li 《World Journal of Psychiatry》 2025年第5期241-256,共16页
BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influenc... BACKGROUND Exploring hypnotherapy's potential to modulate attention bias offers promising avenues for treating social anxiety disorder(SAD).AIM To determine if hypnotherapy can alleviate social anxiety by influencing attention bias,specifically identifying the aspects of attention processes affected by hypnosis.METHODS In this study,69 SAD participants were divided into three groups based on their Liebowitz Social Anxiety Scale scores:Experimental group,control group,and baseline group.The experimental group(n=23)underwent six weekly hypnosis sessions,while the control(n=23)and baseline groups(n=23)received no treatment.To evaluate alterations in SAD severity and attention bias towards threatening stimuli following hypnotherapy,we employed a combination of self-report questionnaires,an odd-one-out task,and electroencephalography recordings.RESULTS The experimental group showed significant reductions in P1,N170,N2pc,and late positive potential(LPP)brain wave activities during attention sensitivity and disengagement conditions.This indicates that hypnotherapy modulates early-stage face processing and later-stage emotional evaluation of threat-related stimuli in SAD patients.CONCLUSION Our findings highlight P1,N170,N2pc,and LPP as key neural markers in SAD treatment.By identifying these neural markers influenced by hypnotherapy,we offer insight into the mechanisms by which this treatment modality impacts attentional processes,potentially easing SAD symptoms. 展开更多
关键词 Social anxiety disorder Attention bias HYPNOTHERAPY Event-related potentials Face processing
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Unchanged top surface-state structures in three-dimensional topological insulator Sb_(2)Te_(3) thin films in the presence of bottom-surface moiré potentials
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作者 Dezhi Song Fuyang Huang +1 位作者 Jun Zhang Ye-Ping Jiang 《Chinese Physics B》 2025年第12期400-404,共5页
The exertion of a long-period potential on two-dimensional(2D)systems leads to band-structure downfolding and the formation of mini flat bands,thereby providing a route for band engineering and enabling the realizatio... The exertion of a long-period potential on two-dimensional(2D)systems leads to band-structure downfolding and the formation of mini flat bands,thereby providing a route for band engineering and enabling the realization of new physical phenomena through the tuning of electron–electron interactions.In this work,the effect of the moiré superlattice formed between the substrate and the bottom quintuple layer(QL)of 3-and 4-QL three-dimensional(3D)topological insulator Sb_(2)Te_(3) thin films on the top surface states is investigated.The scanning tunneling spectra reveal that the bulk-like bands exhibit potential variations consistent with the moirépattern.In contrast,the surface states display only minimal potential variations,resulting in the absence of mini-band formation in the top surface states.These surface states remain nearly unaffected,as confirmed by Landau-level spectroscopy and simulations.The results suggest distinct roles of the bottom-surface moirépotential on the bulk states and the top surface states in the weak coupling regime between the two surfaces. 展开更多
关键词 scanning tunneling spectroscopy topological surface states HETEROSTRUCTURE moirépotential
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Natural Tourism in Kosovo and the Potentials of the Dukagjin Region
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作者 Alberta Tahiri Anela Džogović +13 位作者 Idriz Kovaçi Thëllëza Latifi Sadrija Nora Draga Elvira Misini Ardiana Hyseni Selvije Lajqi Doresa Mulaj Fatbardha Shala Hyrije Bajramaj Kushtrim Agaj Flaka Muriqi Mimoza Mekuli Ismet Berisha Mendim Nimonaj 《Journal of Environmental & Earth Sciences》 2025年第3期274-285,共12页
This study aims to assess the potential of natural tourism in Kosovo,especially in the Dukagjin region as a case study.The main objective is to identify and analyze this region’s tourism potential to understand its i... This study aims to assess the potential of natural tourism in Kosovo,especially in the Dukagjin region as a case study.The main objective is to identify and analyze this region’s tourism potential to understand its impact and importance.180 respondents from the Dukagjin region participated in this study,and the quantitative method was used as a methodology.The measurement instrument consisted of 30 closed questions,which aimed to collect detailed information on the potential of natural tourism in this area.The study results showed that mountain,cultural,winter,healing,and rural tourism are especially important for developing the Dukagjin region.Furthermore,the analysis shows that 30%of the tourism potential is explained by rural tourism,underlining its importance in the local economy.Finally,the study’s findings are discussed,emphasizing their practical value for promoting and developing sustainable tourism in the region. 展开更多
关键词 Development Dukagjin Region Natural Tourism Rural Tourism Tourist potentials Tourism Promotion
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Numerical solution of the Dirac equation with scalar,vector,and tensor potentials
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作者 Alexander Wallén Kiessling Daniel Karlsson +2 位作者 Yuxin Zhao Mário Bettencourt Amaro Chong Qi 《Nuclear Science and Techniques》 2025年第12期244-250,共7页
Solving the Dirac equation has played an important role in many areas of fundamental physics.In this work,we present the Dirac equation solver DiracSVT,which solves the Dirac equation with scalar,vector,and tensor nuc... Solving the Dirac equation has played an important role in many areas of fundamental physics.In this work,we present the Dirac equation solver DiracSVT,which solves the Dirac equation with scalar,vector,and tensor nuclear potentials in spherical coordinate space.The shooting method was used with a Runge–Kutta 4 integration scheme.The potentials are parameterized in a Woods–Saxon form,which reproduce well the known single-particle states around all doubly magic nuclei and can be applied to study the shell evolution of exotic nuclei.The code can be easily extended to the study of other systems,including atomic,hadron,and molecular physics. 展开更多
关键词 Dirac equation Nuclear physics SCALAR Vector and tensor potentials Shell evolution
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Three-component soliton states in spinor F=1 Bose-Einstein condensates with PT-symmetric generalized Scarf-Ⅱpotentials
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作者 Zhang-Lei Han Jun-Yi Lao +1 位作者 Jia-Rui Zhang Yu-Jia Shen 《Communications in Theoretical Physics》 2025年第4期1-11,共11页
Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensat... Introducing PT-symmetric generalized Scarf-Ⅱpotentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seek stable soliton states in quasi-onedimensional spin-1 Bose-Einstein condensates.In scenarios where the spin-independent parameter c_(0)and the spin-dependent parameter c_(2)vary,we use both analytical and numerical methods to investigate the three-coupled nonlinear Gross-Pitaevskii equations with PT-symmetric generalized Scarf-Ⅱpotentials.We obtain analytical soliton states and find that simply modulating c_(2)may change the analytical soliton states from unstable to stable.Additionally,we obtain numerically stable double-hump soliton states propagating in the form of periodic oscillations,exhibiting distinct behavior in energy exchange.For further investigation,we discuss the interaction of numerical double-hump solitons with Gaussian solitons and observe the transfer of energy among the three components.These findings may contribute to a deeper understanding of solitons in Bose-Einstein condensates with PT-symmetric potentials and may hold significance for both theoretical understanding and experimental design in related physics experiments. 展开更多
关键词 three-component soliton states PT-symmetric generalized Scarf-Ⅱpotentials Bose-Einstein condensates Three-coupled nonlinear Gross-Pitaevskii equations
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Delocalized Nonlinear Vibrational Modes in Bcc Lattice for Testing and Improving Interatomic Potentials
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作者 Denis S.Ryabov IgorV.Kosarev +2 位作者 Daxing Xiong Aleksey A.Kudreyko Sergey V.Dmitriev 《Computers, Materials & Continua》 2025年第3期3797-3820,共24页
Molecular dynamics(MD)is a powerful method widely used in materials science and solid-state physics.The accuracy of MD simulations depends on the quality of the interatomic potentials.In this work,a special class of e... Molecular dynamics(MD)is a powerful method widely used in materials science and solid-state physics.The accuracy of MD simulations depends on the quality of the interatomic potentials.In this work,a special class of exact solutions to the equations of motion of atoms in a body-centered cubic(bcc)lattice is analyzed.These solutions take the form of delocalized nonlinear vibrational modes(DNVMs)and can serve as an excellent test of the accuracy of the interatomic potentials used in MD modeling for bcc crystals.The accuracy of the potentials can be checked by comparing the frequency response of DNVMs calculated using this or that interatomic potential with that calculated using the more accurate ab initio approach.DNVMs can also be used to train new,more accurate machine learning potentials for bcc metals.To address the above issues,it is important to analyze the properties of DNVMs,which is the main goal of this work.Considering only the point symmetry groups of the bcc lattice,34 DNVMs are found.Since interatomic potentials are not used in finding DNVMs,they are exact solutions for any type of potential.Here,the simplest interatomic potentials with cubic anharmonicity are used to simplify the analysis and to obtain some analytical results.For example,the dispersion relations for small-amplitude phonon modes are derived,taking into account interactions between up to the fourth nearest neighbor.The frequency response of the DNVMs is calculated numerically,and for some DNVMs examples of analytical analysis are given.The energy stored by the interatomic bonds of different lengths is calculated,which is important for testing interatomic potentials.The pros and cons of using DNVMs to test and improve interatomic potentials for metals are discussed.Since DNVMs are the natural vibrational modes of bcc crystals,any reliable interatomic potential must reproduce their properties with reasonable accuracy. 展开更多
关键词 Interatomic potentials molecular dynamics bcc lattice long-range interactions dispersion relation nonlinear dynamics exact solution delocalized nonlinear vibrational mode
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Characteristics and Simulation Analysis of Ground Potential Waveform under Artificially Triggered Lightning
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作者 GUO Zai-hua CHEN Shao-dong +2 位作者 WU Xiang-hui YAN Xu LYU Wei-tao 《Journal of Tropical Meteorology》 2026年第1期96-106,共11页
In this study, the ground potential rise(GPR) phenomenon caused by a lightning current injected into a field-shaped artificial grounding grid, as well as the potential difference between two different nodes at the edg... In this study, the ground potential rise(GPR) phenomenon caused by a lightning current injected into a field-shaped artificial grounding grid, as well as the potential difference between two different nodes at the edge of the grounding grid, was observed and analyzed under artificially triggered lightning conditions. Based on circuit theory and measured current data, a π-equivalent circuit was established to simulate the transient response of the grounding grid.Nineteen return strokes from three artificially triggered lightning events were analyzed. The peak currents of the 19 return strokes range from -6.7 to -25.1 kA, and the mean value was -14.3 kA. The GPR decreased rapidly and formed a subpeak after reaching the initial peak, with the mean value of the initial peak being -148.65 kV and the mean value of the subpeak being -92.87 kV. The GPR induced by the triggered lightning currents exhibited a subpeak phenomenon. Simulation results indicate that the subpeak phenomenon is related to localized corrosion of the vertical grounding electrode. The potential difference at the grounding grid edge exhibited a multi-pulse waveform with alternating polarity, dominated by positive pulses. The peak values of both the positive and negative polarity pulses gradually decreased, with the first positive pulse displaying a significantly higher intensity than that of subsequent pulses. 展开更多
关键词 artificially triggered lightning grounding grid return stroke ground potential rise potential difference
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Modeling stopping power of ions in plasmas using parametric potentials
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作者 Tanguy Barges Delattre Sébastien Rassou Jean-Christophe Pain 《Matter and Radiation at Extremes》 2025年第6期86-100,共15页
We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The... We present a study of the ion stopping power due to free and bound electrons in a warm dense plasma.Our main goal is to propose a method of stopping-power calculation expected to be valid for any ionization degree.The free-electron contribution is described by the Maynard–Deutsch–Zimmerman formula,and the bound-electron contribution relies on the Bethe formula with corrections,in particular taking into account density and shell effects.The results of the bound-state computation using three different parametric potentials are investigated within the Garbet formalism for the mean excitation energy.The first parametric potential is due to Green,Sellin,and Zachor,the second one was proposed by Yunta,and the third one was introduced by Klapisch in the framework of atomic-structure computations.The results are compared with those of self-consistent average-atom calculations.This approach correctly bridges the limits of neutral and fully ionized matter. 展开更多
关键词 warm dense plasmaour free bound electrons maynard deutsch zimmerman formulaand parametric potentials ion stopping power bethe formula free electrons bound electrons
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Revealing the dynamic responses of Pb under shock loading based on DFT-accuracy machine learning potential
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作者 Enze Hou Xiaoyang Wang Han Wang 《Chinese Physics B》 2026年第1期57-64,共8页
Lead(Pb)is a typical low-melting-point ductile metal and serves as an important model material in the study of dynamic responses.Under shock-wave loading,its dynamic mechanical behavior comprises two key phenomena:pla... Lead(Pb)is a typical low-melting-point ductile metal and serves as an important model material in the study of dynamic responses.Under shock-wave loading,its dynamic mechanical behavior comprises two key phenomena:plastic deformation and shock-induced phase transitions.The underlying mechanisms of these processes are still poorly understood.Revealing these mechanisms remains challenging for experimental approaches.Non-equilibrium molecular dynamics(NEMD)simulations are an alternative theoretical tool for studying dynamic responses,as they capture atomic-scale mechanisms such as defect evolution and deformation pathways.However,due to the limited accuracy of empirical interatomic potentials,the reliability of previous NEMD studies has been questioned.Using our newly developed machine learning potential for Pb-Sn alloys,we revisited the microstructural evolution in response to shock loading under various shock orientations.The results reveal that shock loading along the[001]orientation of Pb exhibits a fast,reversible,and massive phase transition and stacking-fault evolution.The behavior of Pb differs from previous studies by the absence of twinning during plastic deformation.Loading along the[011]orientation leads to slow,irreversible plastic deformation,and a localized FCC-BCC phase transition in the Pitsch orientation relationship.This study provides crucial theoretical insights into the dynamic mechanical response of Pb,offering a theoretical input for understanding the microstructure-performance relationship under extreme conditions. 展开更多
关键词 interatomic potentials molecular dynamics shock impacts machine learning
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Sequential phase transformations in Ta_(0.4)Ti_(2)Zr alloy via tensile molecular dynamics simulations with deep potential
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作者 Hongyang Liu Rong Chen +3 位作者 Bo Chen Jingzhi He Dongdong Kang Jiayu Dai 《Chinese Physics B》 2026年第1期46-55,共10页
Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular ... Understanding the complex deformation mechanisms of non-equimolar multi-principal element alloys(MPEAs)requires high-fidelity atomic-scale simulations.This study develops a deep potential(DP)model to enable molecular dynamics simulations of the Ta_(0.4)Ti_(2)Zr(Ta_(0.4))alloy.Monte Carlo simulations using this potential reveal Ta atom precipitation in the Ta_(0.4)alloy.Under uniaxial tensile loading along the[100]direction in the NPT ensemble,the alloy undergoes a remarkable sequence of phase transformations:an initial body-centered cubic(BCC_(1))to face-centered cubic(FCC)transformation,followed by a reverse transformation from FCC to a distinct BCC phase(BCC_(2)),and finally a BCC_(2) to hexagonal close-packed(HCP)transformation.Critically,the reverse FCC to BCC_(2) transformation induces significant volume contraction.We demonstrate that the inversely transformed BCC_(2) phase primarily accommodates compressive stress.Concurrently,the reorientation of BCC_(2) crystals contributes substantially to the observed high strain hardening.These simulations provide atomic-scale insights into the dynamic structural evolution,sequential phase transformations,and stress partitioning during deformation of the Ta_(0.4)alloy.The developed DP model and the revealed mechanisms offer fundamental theoretical guidance for accelerating the design of high-performance MPEAs. 展开更多
关键词 multi-principal element alloys machine-learning potential phase transformation stress partitioning
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Structures and dynamics of helium in liquid lithium:A study by deep potential molecular dynamics
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作者 Xinyu Zhu Jianchuan Liu +5 位作者 Tao Chen Xinyue Xie Jin Wang Yi Xie Chenxu Wang Mohan Chen 《Chinese Physics B》 2026年第1期25-33,共9页
Current experimental techniques still face challenges in clarifying the structural and dynamic properties of helium(He)in liquid lithium(Li).A critical example of this technical hurdle is the formation of He bubbles,w... Current experimental techniques still face challenges in clarifying the structural and dynamic properties of helium(He)in liquid lithium(Li).A critical example of this technical hurdle is the formation of He bubbles,which significantly affects the transport of He within liquid Li—a vital aspect when considering liquid Li as a plasma-facing material in nuclear fusion reactors.We develop a machine-learning-based deep potential(DP)with ab initio accuracy for the Li-He system and perform molecular dynamics simulations at temperatures ranging from 470 K to 1270 K with a wide range of He concentrations.We observe that He atoms exhibit a tendency to aggregate and form clusters and bubbles in liquid Li.Notably,He clusters exhibit a significant increase in size at elevated temperatures and high concentrations of He,accompanied by the phase separation of Li and He atoms.We also observe an anomalous non-linear relationship between the diffusion coefficient of He and temperature,which is attributed to the larger cluster size at higher temperatures.Our study provides a deeper understanding of the behavior of He in liquid Li and further supports the potential application of liquid Li under extreme conditions. 展开更多
关键词 MD simulation machine-learning-based deep potential plasma-facing material He in liquid Li
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Global Well-Posedness for the Inhomogeneous Fourth-Order Schr¨odinger Equation with Potential
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作者 XIA Su-xia LI Shuo 《Chinese Quarterly Journal of Mathematics》 2026年第1期82-91,共10页
The paper considers the initial value problem of inhomogeneous fourth-order Schr¨odinger equation with potential in energy space H^(2)(R^(d)).The global well-posedness is obtained in dimensions d≥5 resorting to ... The paper considers the initial value problem of inhomogeneous fourth-order Schr¨odinger equation with potential in energy space H^(2)(R^(d)).The global well-posedness is obtained in dimensions d≥5 resorting to contractive mapping principle,Strichartz estimates,Caffarelli-Kohn-Nirenberg-type inequality and the continuity method. 展开更多
关键词 WELL-POSEDNESS Inhomogeneous fourth-order Schr¨odinger equation potentiAL Strichartz estimates Continuity method
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Oxidative potential of PM_(2.5) in Guangzhou,Southern China:Source apportionment and association with airborne bacteria
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作者 Yuxin Huang Senchao Lai +7 位作者 Baoling Liang Jinpu Zhang Chenglei Pei Dachi Hong Xiaoluan Lin Zhaokang Ruan Leitao Sun Yingyi Zhang 《Journal of Environmental Sciences》 2026年第1期64-72,共9页
Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China ... Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China in winter and spring of 2021.The results show that the average concentration of PM_(2.5) decreased by 47%from winter to spring,while volume-normalized and mass-normalized OP(i.e.,OP_(v) and OP_(m))increased by 6%and 69%,respectively.It suggests that the decline of PM_(2.5) may not necessarily decrease the health risks and the intrinsic toxicity of PM_(2.5).Variations of OP_(v) and OP_(m) among different periods were related to the different source contributions and environmental conditions.The positive matrix factorization model was used to identify the major sources of OP_(v).OP_(v) was mainly contributed by biomass burning/industrial emissions(29%),soil/road dust(20%),secondary sulfate(14%),and coal combustion(13%)in winter.Different major sources were resolved to be secondary sulfate(36%),biological sources(21%),and marine vessels(20%)in spring,presenting the substantial contribution of biological sources.The analysis shows strong associations between OP_(v) and both live and dead bacteria,further confirming the important contribution of bioaerosols to the enhancement of OP.This study highlights the importance of understanding OP in ambient PM_(2.5) in terms of public health impact and provides a new insight into the biological contribution to OP. 展开更多
关键词 Oxidative potential PM_(2.5) Source apportionment Positive matrix factorization Airborne bacteria
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