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Stationary Classical Chaos of Trapped Two-Component Bose-Einstein Condensates in 1-D Optical Lattice Potentials
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作者 FANG Jian-Shu LIU Wing-Ki ZHU Shan-Hua1 Institute of Physics,Hunan University of Technology,Zhuzhou 412008,China2 Department of Physics,Hunan Normal University,Changsha 410081,China3 Department of Physics,University of Waterloo,Waterloo,Ontario,Canada N2L 3G1 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期125-131,共7页
We study the nonlinear dynamics of two-component Bose-Einstein condensates in one-dimensional pe-riodic optical lattice potentials.The stationary state perturbation solutions of the coupled two-component nonlinearSchr... We study the nonlinear dynamics of two-component Bose-Einstein condensates in one-dimensional pe-riodic optical lattice potentials.The stationary state perturbation solutions of the coupled two-component nonlinearSchr?dinger/Gross-Pitaevskii equations are constructed by using the direct perturbation method.Theoretical analysisrevels that the perturbation solution is the chaotic one,which indicates the existence of chaos and chaotic region inparameter space.The corresponding numerical calculation results agree well with the analytical results.By applying thechaotic perturbation solution,we demonstrate the atomic spatial population and the energy distribution of the systemare chaotic generally. 展开更多
关键词 stationary state classical chaos two-component Bose-Einstein condensates optical lattice potential
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RELATIONS BETWEEN PERFORMANCE POTENTIALS AND INFINITESIMAL REALIZATION FACTORS IN CLOSED QUEUEING NETWORKS
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作者 YinBaoqun DaiGuiping +1 位作者 XiHongsheng YangXiaoxian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第4期458-464,共7页
In this paper,the concept of the infinitesimal realization factor is extended to the parameter dependent performance functions in closed queueing networks.Then the concepts of realization matrix (its elements are cal... In this paper,the concept of the infinitesimal realization factor is extended to the parameter dependent performance functions in closed queueing networks.Then the concepts of realization matrix (its elements are called realization factors) and performance potential are introduced,and the relations between infinitesimal realization factors and these two quantities are discussed.This provides a united framework for both IPA and non IPA approaches.Finally,another physical meaning of the service rate is given. 展开更多
关键词 closed queueing networks performance function performance potential realization matrix infinitesimal realization factor.
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Second-Order Potentials and Forces for Two-Dimensional Diffraction Problem of Finite Water Depth
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作者 Duan Wenyang and He Wuzhou Graduate student, Department of Naval Architecture and Ocean Engineering, Harbin Engineering University, Harbin 150001 . Associate Professor, Department of Hydraulic Engineering, Tsinghua University 《China Ocean Engineering》 SCIE EI 1994年第3期321-330,共10页
-In this paper, an analytical solution in the outer region of finite water depth is derived for the second-order diffraction potential, which gives a clear physical meaning of the wave transmission and reflection char... -In this paper, an analytical solution in the outer region of finite water depth is derived for the second-order diffraction potential, which gives a clear physical meaning of the wave transmission and reflection characteristics in the far field. A numerical method-simple Green's function technique-for calculating the second-order diffraction potential in the inner region is also described. Numerical results are provided for the second-order wave forces on a semi-submerged cylinder. It is found that the contribution of second-order diffraction potential to second-order wave forces is important. The effect of water depth and submerged depth on the wave force is also discussed. 展开更多
关键词 second-order diffraction potential second-order wave forces
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Relationship Between Two Classes of Shape-Invariant Potentials
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作者 QIAN Shang-Wu GU Zhi-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第10期391-394,共4页
We show that two classes of shape-invariant potentials are interrelated to each other. For all one-dimensional shape-invariant potentials with parameters related by translation, i.e. the first class of shapc-invariant... We show that two classes of shape-invariant potentials are interrelated to each other. For all one-dimensional shape-invariant potentials with parameters related by translation, i.e. the first class of shapc-invariant potentials (SIP1),we can find their multi-parameter deformations with q acting as the deformation parameter, i.e. the second class of shape-invariant potentials (SIP2) with parameters related by scaling. In order to get closed solution of SIP2, we consider two infinitesimal intervals, one is close to q= 0 another close to q = 1, and show that in these intervals we can get separately two first-order approximate solutions in closed form, furthermore we prove that all SIP1 can be obtained by the limiting procedures for corresponding SIP2. 展开更多
关键词 shape-invariant potential superpotential MULTI-PARAMETER DEFORMATION
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Construction of Wave-free Potentials and Multipoles in a Two-layer Fluid Having Free-surface Boundary Condition with Higher-order Derivatives 被引量:1
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作者 Dilip Das 《Journal of Marine Science and Application》 CSCD 2015年第3期270-282,共13页
There is a large class of problems in the field of fluid structure interaction where higher-order boundary conditions arise for a second-order partial differential equation. Various methods are being used to tackle th... There is a large class of problems in the field of fluid structure interaction where higher-order boundary conditions arise for a second-order partial differential equation. Various methods are being used to tackle these kind of mixed boundary-value problems associated with the Laplace’s equation (or Helmholtz equation) arising in the study of waves propagating through solids or fluids. One of the widely used methods in wave structure interaction is the multipole expansion method. This expansion involves a general combination of a regular wave, a wave source, a wave dipole and a regular wave-free part. The wave-free part can be further expanded in terms of wave-free multipoles which are termed as wave-free potentials. These are singular solutions of Laplace’s equation or two-dimensional Helmholz equation. Construction of these wave-free potentials and multipoles are presented here in a systematic manner for a number of situations such as two-dimensional non-oblique and oblique waves, three dimensional waves in two-layer fluid with free surface condition with higher order partial derivative are considered. In particular, these are obtained taking into account of the effect of the presence of surface tension at the free surface and also in the presence of an ice-cover modelled as a thin elastic plate. Also for limiting case, it can be shown that the multipoles and wave-free potential functions go over to the single layer multipoles and wave-free potential. 展开更多
关键词 two-layer fluid wave-free potentials Laplace’s equation modified Helmholtz equations higher order boundary conditions MULTIPOLES
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Solutions of the Schrdinger Equation for PT-Symmetric Coupled Quintic Potentials in Two Dimensions
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作者 Savita Fakir Chand 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第9期419-422,共4页
This paper deals with the solutions of time independent Schrodinger wave equation for a two-dimensional PT-symmetric coupled quintic potential in its most general form. Employing wavefunction ansatz method, general an... This paper deals with the solutions of time independent Schrodinger wave equation for a two-dimensional PT-symmetric coupled quintic potential in its most general form. Employing wavefunction ansatz method, general analytic expressions for eigenvalues and eigenfunctions for first four states are obtained. Solutions of a particular case are also presented. 展开更多
关键词 Schrodinger equation quintic potential PT-syrametry EIGENVALUE EIGENFUNCTION
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The optimal distance between two electrode tips during recording of compound nerve action potentials in the rat median nerve
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作者 Yongping Li Jie Lao +3 位作者 Xin Zhao Dong Tian Yi Zhu Xiaochun Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第2期171-178,共8页
The distance between the two electrode tips can greatly influence the parameters used for record- ing compound nerve action potentials. To investigate the optimal parameters for these recordings in the rat median nerv... The distance between the two electrode tips can greatly influence the parameters used for record- ing compound nerve action potentials. To investigate the optimal parameters for these recordings in the rat median nerve, we dissociated the nerve using different methods and compound nerve action potentials were orthodromically or antidromically recorded with different electrode spac- ings. Compound nerve action potentials could be consistently recorded using a method in which the middle part of the median nerve was intact, with both ends dissociated from the surrounding fascia and a ground wire inserted into the muscle close to the intact part. When the distance be- tween two stimulating electrode tips was increased, the threshold and supramaximal stimulating intensity of compound nerve action potentials were gradually decreased, but the amplitude was not changed significantly. When the distance between two recording electrode tips was increased, the amplitude was gradually increased, but the threshold and supramaximal stimulating intensity exhibited no significant change. Different distances between recording and stimulating sites did not produce significant effects on the aforementioned parameters. A distance of 5 mm between recording and stimulating electrodes and a distance of 10 mm between recording and stimulating sites were found to be optimal for compound nerve action potential recording in the rat median nerve. In addition, the orthodromic compound action potential, with a biphasic waveform that was more stable and displayed less interference (however also required a higher threshold and higher supramaximal stimulus), was found to be superior to the antidromic compound action potential. 展开更多
关键词 nerve regeneration peripheral nerve injury compound nerve action potential mediannerve electrodes AMPLITUDE supramaximal stimulus intensity recording electrode the Project 211in China neural regeneration
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Spinor F=1 Bose-Einstein condensates loaded in two types of radially-periodic potentials with spin-orbit coupling
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作者 Ji-Guo Wang Yue-Qing Li +1 位作者 Han-Zhao Tang Ya-Fei Song 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期442-446,共5页
We consider two-dimensional spinor F=1 Bose-Einstein condensates in two types of radially-periodic potentials with spin-orbit coupling,i.e.,spin-independent and spin-dependent radially-periodic potentials.For the Bose... We consider two-dimensional spinor F=1 Bose-Einstein condensates in two types of radially-periodic potentials with spin-orbit coupling,i.e.,spin-independent and spin-dependent radially-periodic potentials.For the Bose-Einstein condensates in a spin-independent radially-periodic potential,the density of each component exhibits the periodic density modulation along the azimuthal direction,which realizes the necklacelike state in the ferromagnetic Bose-Einstein condensates.As the spin-exchange interaction increases,the necklacelike state gradually transition to the plane wave phase for the antiferromagnetic Bose-Einstein condensates with larger spin-orbit coupling.The competition of the spin-dependent radially-periodic potential,spin-orbit coupling,and spin-exchange interaction gives rise to the exotic ground-state phases when the Bose-Einstein condensates in a spin-dependent radially-periodic potential. 展开更多
关键词 spinor Bose-Einstein condensates spin-orbit coupling radially-periodic potential
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Neural Network Detection of Ventricular Late Potentials from Wavelet Preprocessed Vector Magnitude Waves
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作者 WU Shui cai,LIN Jia rui 《Chinese Journal of Biomedical Engineering(English Edition)》 2000年第3期117-125,共9页
A novel method for detection of ventricular late potentials (VLP) using artificial neural network (ANN) from wavelet preprocessed vector magnitude waves (VMW) is proposed. The VMW is firstly processed with a continuou... A novel method for detection of ventricular late potentials (VLP) using artificial neural network (ANN) from wavelet preprocessed vector magnitude waves (VMW) is proposed. The VMW is firstly processed with a continuous wavelet transform (CWT). Then eight features are extracted from time frequency energy distribution of VMW, and are inputted into ANN for VLP detection. The ANN is trained with 40 clinical samples and tested using another 38 clinical samples, respectively. The results show that the specifically designed ANN can detect VLP with the high rate of correct classification (93.33%), and can enhance the sensitivity and specificity of VLP detection as compared with conventional time domain method. 展开更多
关键词 VENTRICULAR LATE potentials WAVELET transform Artificial neural networks
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Mass Increase with Strong and Gravitational Potentials, and Mass Defect with Electromagnetic Potential
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作者 Hany Ali Hussein 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1079-1094,共16页
The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons,... The proposal is “mass increases due to strong and gravitational potentials, while it decreases due to Electromagnetic potential”. This proposal explains the big difference in mass between hadrons (protons, neutrons, & mesons) and their components (quarks), mass difference between nucleus and its individual components (protons and neutrons), massless of gamma photons, abnormal masses of mesons and bosons, and the excess in galaxy masses (dark matter). Also, this proposal shows the exact relation between mass and energy: Strong Potential=−3.04mc2| Electric Potential |=−5.57×10−3mc2Gravitational Potential=−1.22×10−7mc2where m represents the excess in mass due to strong potential, or gravitational potential and represents the decrease in mass due to electromagnetic potential. Released energy here equals potential energy and doesn’t equal decrease in mass using the formula E = mc2. Released energy is transferred to heat, photons, kinetic energy… Finally, proposal will try to describe the relation between photon energy and mass of its components using the general equation of kinetic energy: Photon Energy=1/2mc2m is the sum of the individual masses of its components, while the total mass of photon is zero. 展开更多
关键词 Mass Defect Dark Matter PHOTON Gamma Photon Strong Potential Gravitational Potential Electromagnetic Potential QUARKS Mesons BOSONS Deuterium Proton Neutron
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Median Nerve Somatosensory Evoked Potentials in Patients with Chiari Malformation
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作者 Mustafa Harun Sahin Gonul Vural +1 位作者 Serdar Barakli Sadiye Gumusyayla 《World Journal of Neuroscience》 CAS 2024年第1期24-32,共9页
Abnormal SEP reflects dysfunction of the medial lemniscus and posterior cervical cord. These structures are likely to be affected in Chiari malformation. Therefore, SEP abnormalities may provide valuable information i... Abnormal SEP reflects dysfunction of the medial lemniscus and posterior cervical cord. These structures are likely to be affected in Chiari malformation. Therefore, SEP abnormalities may provide valuable information in patients with CM. However, the consistency of SEP abnormality or normality with the damage is a matter of research. Knowing whether median nerve somatosensory evoked potential (SEP) is useful in revealing subclinical damage in patients with Chiari malformation is important in the treatment and follow-up plan of the disease. The aim of this study was to investigate the relationship between median nerve SEP values and the severity of cerebellar ectopia in patients with Chiari type 1 malformation. Median nerve SEP values were obtained from 30 healthy individuals and 146 individuals with Chiari malformation. The cerebellar ectopia degree and McRae line length were measured. SEP values were not significantly different between groups. The McRae line was found to be significantly shorter in the control group than in the Chiari malformation group (p = 0.031). There was no correlation between the degree of cerebellar ectopia and the length of the McRae line (r = 0.002, p = 0.979). Neither cerebellar ectopy degree nor McRae line length had a relationship with SEP values (r = -0.153, p = 0.066;r = -0.056, p = 0.500, respectively). There was no difference in cerebellar ectopy degree or SEP values between the groups with cerebellar ectopy with and without a syrinx (p = 0.899;p = 0.080, respectively). Likewise, McRae line length was not found to be related to the presence of a syrinx (p = 0.139). Median nerve SEP examination was not beneficial for diagnosing asymptomatic-oligosymptomatic Chiari malformation as a subclinical injury, whether accompanied by syringomyelia or not. 展开更多
关键词 Chiari Malformation Cerebellar Ectopy Somatosensory Evoked Potential
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A robust method for evaluating the potentials of 15-minute cities:Implications for sustainable urban futures
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作者 Jianying Wang Mei-Po Kwan +1 位作者 Gezhi Xiu Fangxu Deng 《Geography and Sustainability》 CSCD 2024年第4期597-606,共10页
The‘15-minute city’(15minC)concept,which aspires to bring essential services within reach via a 15-minute walk for all residents,represents a pivotal paradigm shift in sustainable urban development.However,the achie... The‘15-minute city’(15minC)concept,which aspires to bring essential services within reach via a 15-minute walk for all residents,represents a pivotal paradigm shift in sustainable urban development.However,the achievability of this concept for different cities varies considerably across diverse population distributions,urban contexts,and development priorities.In this study,we propose a robust method for evaluating a city’s 15minC potential-a city’s capability to achieve widespread 15-minute accessibility while maintaining an optimal balance between resource efficiency and resident accessibility.We employ the Location Set Covering Problem optimization model to analyze the resources required to achieve full coverage of 15-minute accessibility and the knee point detection algorithm to assess a city’s 15minC potential.Across 23 major Chinese cities,our method exhibits a sharp sensitivity to delineate distinct 15minC potentials.It reveals that cities’current 15minC development level doesn’t align with their inherent potential uniformly.Key determinants include how well current facility locations match population centers and the population density in remote areas.Further,reducing facility constructions by twothirds has only a marginal impact on accessibility,emphasizing the need for tailored,data-driven planning in effective and sustainable urban development based on the distinct potentials of cities.Our approach prioritizes resource efficiency,minimizing the inefficient use of facilities that serve only a small portion of residents while maximizing the benefits of the 15minC and therefore has significant implications for a sustainable urban future. 展开更多
关键词 15-Minute city Development potential SUSTAINABILITY Efficiency
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Thermal conductivity of GeTe crystals based on machine learning potentials
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作者 张健 张昊春 +1 位作者 李伟峰 张刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期104-107,共4页
GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussi... GeTe has attracted extensive research interest for thermoelectric applications.In this paper,we first train a neuroevolution potential(NEP)based on a dataset constructed by ab initio molecular dynamics,with the Gaussian approximation potential(GAP)as a reference.The phonon density of states is then calculated by two machine learning potentials and compared with density functional theory results,with the GAP potential having higher accuracy.Next,the thermal conductivity of a GeTe crystal at 300 K is calculated by the equilibrium molecular dynamics method using both machine learning potentials,and both of them are in good agreement with the experimental results;however,the calculation speed when using the NEP potential is about 500 times faster than when using the GAP potential.Finally,the lattice thermal conductivity in the range of 300 K-600 K is calculated using the NEP potential.The lattice thermal conductivity decreases as the temperature increases due to the phonon anharmonic effect.This study provides a theoretical tool for the study of the thermal conductivity of GeTe. 展开更多
关键词 machine learning potentials thermal conductivity molecular dynamics
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Global dust density in two-dimensional complex plasma
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作者 赵逸真 刘松芬 +1 位作者 孔伟 杨芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期445-450,共6页
The driven-dissipative Langevin dynamics simulation is used to produce a two-dimensional(2D) dense cloud, which is composed of charged dust particles trapped in a quadratic potential. A 2D mesh grid is built to analyz... The driven-dissipative Langevin dynamics simulation is used to produce a two-dimensional(2D) dense cloud, which is composed of charged dust particles trapped in a quadratic potential. A 2D mesh grid is built to analyze the center-to-wall dust density. It is found that the local dust density in the outer region relative to that of the inner region is more nonuniform,being consistent with the feature of quadratic potential. The dependences of the global dust density on equilibrium temperature, particle size, confinement strength, and confinement shape are investigated. It is found that the particle size, the confinement strength, and the confinement shape strongly affect the global dust density, while the equilibrium temperature plays a minor effect on it. In the direction where there is a stronger confinement, the dust density gradient is bigger. 展开更多
关键词 dust particles quadratic potential two-dimensional mesh grid
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Clinical characteristics and analysis of vestibular-evoked myogenic potentials in patients with sudden sensorineural hearing loss in different ages
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作者 Yan-Zhuo Zhang Ya-Bo Wang +6 位作者 Jing-Lei Fang Yue-Tang Wang Gui-Fang Li Ran-Ran Liu Shu-Jing Shi Chun-Hua Wang Yong-Tao Tian 《World Journal of Clinical Cases》 SCIE 2024年第19期3760-3766,共7页
BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studi... BACKGROUND Numerous studies have found that patients experiencing sudden sensorineural hearing loss(SSHL),with or without accompanying vertigo,often show impaired vestibular function.However,there is a dearth of studies analyzing vestibularevoked myogenic potentials(VEMPs)in SSHL patients across various age groups.AIM To investigate vestibular condition in SSHL patients across various age demographics.METHODS Clinical data of 84 SSHL patients were investigated retrospectively.Audiometry,cervical vestibular evoked myogenic potentials(c-VEMPs),and ocular vestibular evoked myogenic potentials(o-VEMPs)were conducted on these patients.Parameters assessed included the latencies of P1 and N1 waves,as well as the amplitudes of P1–N1 waves.Moreover,the study evaluated the influence of factors such as sex,affected side,configuration of hearing loss,and presence of accompanying vertigo.RESULTS Among the 84 SSHL patients,no significant differences were observed among the three groups in terms of gender,affected side,and the presence or absence of vertigo.Group II(aged 41–60 years)had the highest number of SSHL cases.The rates of absent o-VEMPs in the affected ears were 20.83%,31.58%,and 22.72%for the three age groups,respectively,with no statistically significant difference among them.The rates of absent c-VEMPs in the affected ears were 8.3%,34.21%,and 18.18%for the three age groups,respectively,with significant differences.In the unaffected ears,there were differences observed in the extraction rates of o-VEMPs in the unaffected ears among the age groups.In the three age groups,no significant differences were noted in the three age groups in the latencies of P1 and N1 waves or in the amplitude of N1–P1 waves for c-VEMPs and o-VEMPs,either on the affected side or on the unaffected side,across the three age groups.CONCLUSION The extraction rate of VEMPs is more valuable than parameters.Regardless of the presence of vertigo,vestibular organs are involved in SSHL.Notably,SSHL patients aged 41–60 appear more susceptible to damage to the inferior vestibular nerve and saccule. 展开更多
关键词 Sudden sensorineural hearing loss Cervical vestibular evoked myogenic potential Ocular vestibular evoked myogenic potential VERTIGO Pure tone audiometry
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Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications
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作者 Weikang Hu Jiaqi Xu +3 位作者 Nanjie Chen Zongcai Deng Yuekun Lai Dongyang Chen 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期899-908,共10页
The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution gr... The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries. 展开更多
关键词 Non-aqueous redox flow batteries Tetrathiofulvarene Redox potential SOLUBILITY Substituent effect
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The Aharonov-Bohm Effect: An Exploration of Quantum Interference and Electromagnetic Potentials
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 CAS 2024年第3期79-87,共9页
The AB(Aharonov-Bohm)effect is a pivotal quantum mechanical phenomenon that illustrates the fundamental role of the electromagnetic vector potential A in determining the phase of a charged particle’s wave function,ev... The AB(Aharonov-Bohm)effect is a pivotal quantum mechanical phenomenon that illustrates the fundamental role of the electromagnetic vector potential A in determining the phase of a charged particle’s wave function,even in regions where the magnetic field B is zero.This effect demonstrates that quantum particles are influenced not only by the fields directly present but also by the potentials associated with those fields.In the AB effect,an electron beam is split into two paths,with one path encircling a solenoid and the other bypassing it.Despite the absence of a magnetic field in the regions traversed by the beams,the vector potential A associated with the magnetic flux Φ through the solenoid induces a phase shift in the electron’s wave function.This phase shift,quantified by △φ=qΦ/hc,manifests as a change in the interference pattern observed in the detection screen.The phenomenon underscores the principle of gauge invariance in QED(quantum electrodynamics),where physical observables remain invariant under local gauge transformations of the vector and scalar potentials.This reinforces the notion that the vector potential A has a profound impact on quantum systems,beyond its classical role.This article outlines the AB effect,including its theoretical framework,experimental observations,and implications.The focus on the role of the vector potential in quantum mechanics provides a comprehensive understanding of this important phenomenon. 展开更多
关键词 AB effect vector potential(A) magnetic flux(Φ) quantum phase shift gauge invariance electromagnetic potentials interference pattern scalar fields longitudinal waves QED
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Masseter Vestibular evoked myogenic potentials: A new tool to assess the vestibulomasseteric reflex pathway
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作者 Aishwarya Nagarajan Sujeet Kumar Sinha 《Journal of Otology》 CAS CSCD 2024年第1期46-54,共9页
Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials(mVEMP). The article also ... Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials(mVEMP). The article also reviews the contemporary researches involving the clinical applications of the mVEMP. Conclusions: Masseter VEMP is an evolving yet clinically promising neuro-otology test tool that has recently gained more research interest and is considered an additional tool to diagnose various vestibular disorders. Masseter VEMP assesses the functional integrity of the acoustic-masseteric and vestibulo-masseteric reflex pathways. The mVEMP could be used as a complementary test to evaluate the same peripheral generator as the cervical VEMP but a different central pathway i.e., vestibulo-trigeminal pathway. Various research studies that have experimented on parameters such as the effect of different electrode montages(zygomatic vs mandibular configurations), stimulation rates, filter settings and stimuli used to evoke mVEMP have been discussed in this article that could assist in the optimization of a comprehensive clinical protocol. The latency and the amplitude of mVEMP waveforms serve as significant parameters in differentiating normals from those of the clinical populations. Along with the cVEMPs and oVEMPs, mVEMP might help diagnose brainstem lesions in REM Sleep behaviour disorders, Multiple Sclerosis and Parkinson's disease. However, further studies are required to probe in this area of research. 展开更多
关键词 Masseter vestibular evoked myogenic potentials(mVEMP) Vestibulo-masseteric pathway Acoustic-masseteric pathway
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Entrepreneurship training:its influences on innovation potentials among nursing students
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作者 Asmaa Abdel Rahman Abdel Rahman Dalia Abdallah Abdelatief 《Frontiers of Nursing》 2024年第1期85-98,共14页
Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing students.Methods:A quasi-experimental design was utilized to conduct this study.The study was conducted in th... Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing students.Methods:A quasi-experimental design was utilized to conduct this study.The study was conducted in the classroom at the faculty of nursing,and the“i Hub”center at Ain Shams University(ASU)in Cairo,Egypt.A purposive sample of 42 nursing students who participated in the“Ain Shams University-innovate”competition from the Faculty of Nursing of ASU were included in this study.Data collection tools included(1)Nursing students'innovation skills assessment questionnaire and(2)Innovative projects evaluation tool.Results:There was a statistically significant difference between the mean scores of nursing students'total innovation skills pre-and post-implementation of entrepreneurship training,where P-value<0.05.Conclusions:The results of the current study support the research hypothesis because the implementation of entrepreneurship training positively affects nursing students'innovation potential.Developing entrepreneurship education in nursing and integrating it into nursing programs will stimulate creativity,innovation,and entrepreneurship among nursing students and health care services. 展开更多
关键词 entrepreneurship training innovation potentials nursing students creative skills energy/motivation
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洛河洛阳段沉积物重金属空间分布及潜在生态风险
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作者 刘德鸿 石兆勇 《河南师范大学学报(自然科学版)》 CAS 北大核心 2025年第1期57-65,共9页
为明晰洛河洛阳段沉积物重金属分布、风险及来源,以洛河洛阳段为研究对象,采集入城区段、主城区段和出城区段13个点位的表层沉积物,分析重金属(Pb、Cd、Cr、Mo、Cu和Zn)的空间分特征,并利用地累积指数(I geo)法、潜在生态风险指数(RI)... 为明晰洛河洛阳段沉积物重金属分布、风险及来源,以洛河洛阳段为研究对象,采集入城区段、主城区段和出城区段13个点位的表层沉积物,分析重金属(Pb、Cd、Cr、Mo、Cu和Zn)的空间分特征,并利用地累积指数(I geo)法、潜在生态风险指数(RI)法和主成分分析等方法评价重金属污染程度、潜在生态风险及来源解析,结果显示:洛河洛阳段沉积物重金属平均质量分数Pb(42.90 mg·kg^(-1))、Cd(2.41 mg·kg^(-1))、Cr(76.86 mg·kg^(-1))、Mo(9.31 mg·kg^(-1))、Cu(35.15 mg·kg^(-1))及Zn(145.60 mg·kg^(-1))分别为黄河流域河南段重金属元素土壤背景值的1.7、14.2、1.1、13.7、1.5和2.2倍.Pb、Cr和Cu质量分数均表现为入城区段显著高于出城区段,Cd、Mo和Zn表现为主城区段显著高于出城区段,这6种重金属质量分数在入城区段与主城区段间无显著差异.入城区段和主城区段多数点位的Cd为偏重污染程度及以上,Mo为中度污染或偏重污染程度,其余为轻度或低污染程度.源解析显示,Pb、Cd、Mo、Cu和Zn主要为人为源,Cr以自然源为主.潜在生态风险指数法结果显示,入城区点位达到强生态危害水平(Ⅲ级)及以上,主城区段所有点位均达到很强生态危害水平(Ⅳ级),出城区段所有点位均达到强生态危害水平(Ⅲ级),其中,Cd对RI的贡献最大,占比64.10%,其次是Mo(32.67%).洛阳市应重点关注由钼产业可能引起的环境风险,并进一步降低Cd污染水平,方能降低洛河沉积物重金属的污染及潜在生态风险. 展开更多
关键词 洛河 洛阳段 沉积物 重金属 潜在生态风险
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