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Surface-mediated iron on porous cobalt oxide with high energy state for efficient water oxidation electrocatalysis 被引量:2
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作者 Jingsha Li Tao Hu +1 位作者 Changhong Wang Chunxian Guo 《Green Energy & Environment》 SCIE EI CSCD 2022年第4期662-671,共10页
Surface engineering of active materials to generate desired energy state is critical to fabricate high-performance heterogeneous catalysts.However, its realization in a controllable level remains challenging. Using ox... Surface engineering of active materials to generate desired energy state is critical to fabricate high-performance heterogeneous catalysts.However, its realization in a controllable level remains challenging. Using oxygen evolution reaction(OER) as a model reaction, we report a surface-mediated Fe deposition strategy to electronically tailor surface energy states of porous Co_(3)O_(4)(Fe-pCo_(3)O_(4)) for enhanced activity towards OER. The Fe-pCo_(3)O_(4) exhibits a low overpotential of 280 mV to reach an OER current density of 100 mA cm^(-2), and a fast-kinetic behavior with a low Tafel slop of 58.2 mV dec^(-1), outperforming Co_(3)O_(4)-based OER catalysts recently reported and also the noble IrO_(2). The engineered material retains 100% of its original activity after operating at an overpotential of 350 m V for 100 h. A combination of theoretical calculations and experimental results finds out that the surface doped Fe promotes a high energy state and desired coordination environment in the near surface region, which enables optimized OER intermediates binding and favorably changes the rate-determining step. 展开更多
关键词 Surficial Fe doping Cobalt oxides High energy state Water oxidation Oxygen evolution reactions
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Description of the properties of the low-lying energy states in ^(100)Mo with IBM2 被引量:2
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作者 ZHANG DaLi DING BinGang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第3期447-452,共6页
The properties of the low-lying energy states for the l00 Mo isotope is investigated within the framework of the proton-neutron interacting model IBM2. By considering the relative energy of the d proton boson to be di... The properties of the low-lying energy states for the l00 Mo isotope is investigated within the framework of the proton-neutron interacting model IBM2. By considering the relative energy of the d proton boson to be different from that of the neutron boson and taking into account the dipole interacting among like-boson Lπ·Lπ and Lπ·Lπ, the low-lying energy spectrum is reproduced well. Particularly, the relative position of the energies for 2+1, 0+2, 2+2 and 4+1 states shifted correctly fit the experimental data. The electromagnetic properties, including the key observable B(E2) reduced transition branching ratios and the E2 reduced matrix elements of the experimental data, are well described. Our calculations show possible shape coexistence in the l00Mo nucleus. 展开更多
关键词 100Mo shape coexistence low-ling energy states IBM2.
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Electron energy states in a two-dimensional GaAs quantum ring with hydrogenic donor impurity in the presence of magnetic field 被引量:1
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作者 康云 王升 李贤丽 《Journal of Semiconductors》 EI CAS CSCD 2015年第3期12-18,共7页
Using the finite element method, we investigate the lowest and first few excited state energies in a two- dimensional GaAs quantum ring (QR) with a hydrogenic donor impurity and effective mass approximation under a ... Using the finite element method, we investigate the lowest and first few excited state energies in a two- dimensional GaAs quantum ring (QR) with a hydrogenic donor impurity and effective mass approximation under a uniform magnetic field perpendicular to the ring plane. We study in detail the dependence of the energy spectrum with different angular momentum on the inner radius, the outer radius and width of the QR, the magnetic field and impurity position. The results reveal that the electron energies increase with the inner radius while decrease with the outer radius and width of the QR; for a fixed ring, the magnetic field induces the increase of the electron energies. Moreover, the existence of impurity reduces energy levels, and the energy levels depend highly on the impurity position, which decreases as the impurity is far away from the center of the QR. Also, the dependence of the angular momentum on the energy spectrum is analyzed in detail. 展开更多
关键词 quantum ring hydrogenic donor impurity magnetic field electron energy states
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Cell Evolutionary Algorithm: a New Optimization Method on Ground-State Energy of the Atomic
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作者 Liu Lian-jun, Xu Jing-wen, Mao You-dong, Li Yuan-xiang Department of Physics, Wuhan University, Wuhan 430072,China State Key Laboratory of Software Engineering,Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第4期425-430,共6页
The purpose of this paper is to present a new general approach to solve ground-state energies of the double-electron systems in a uniform magnetic field, in which the basic element of evolution is the set in the solut... The purpose of this paper is to present a new general approach to solve ground-state energies of the double-electron systems in a uniform magnetic field, in which the basic element of evolution is the set in the solution space, rather than the point. The paper defines the Cell Evolutionary Algorithm, which implements such a view of the evolution mechanism. First, the optimal set in which the optimal solution may be obtained. Then this approach applies the embedded search method to get the optimal solution. We tested this approach on the atomic structure, and the results show that it can improve not only the efficiency but also the accuracy of the calculations as it relates to this specific problem. 展开更多
关键词 Key words double electron systems GROUND state energy variational principle cell evolutionary algorithm evolutionary algorithm
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State Grid Contributes to Clean Energy Development
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作者 Zhao Qingbo State Grid Corporation of China Zhang Sufang 《Electricity》 2010年第3期48-50,共3页
The development of clean energy is an inevitable choice for China to achieve sustainable development.The article presents the strategic thinking and measures for the promotion of clean energy development in grids,whic... The development of clean energy is an inevitable choice for China to achieve sustainable development.The article presents the strategic thinking and measures for the promotion of clean energy development in grids,which shows that the company will bear its responsibilities for the development as a large state-owned enterprise. 展开更多
关键词 clean energy state grid energy strategy
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Adaptive Energy-Efficient Power Allocation for DAS with Imperfect Channel State Information and Antenna Selection
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作者 Weiye Xu Min Lin +1 位作者 Yu Yang Xiangbin Yu 《China Communications》 SCIE CSCD 2016年第7期127-134,共8页
Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Ra... Considering that perfect channel state information(CSI) is difficult to obtain in practice,energy efficiency(EE) for distributed antenna systems(DAS) based on imperfect CSI and antennas selection is investigated in Rayleigh fading channel.A novel EE that is defined as the average transmission rate divided by the total consumed power is introduced.In accordance with this definition,an adaptive power allocation(PA) scheme for DAS is proposed to maximize the EE under the maximum transmit power constraint.The solution of PA in the constrained EE optimization does exist and is unique.A practical iterative algorithm with Newton method is presented to obtain the solution of PA.The proposed scheme includes the one under perfect CSI as a special case,and it only needs large scale and statistical information.As a result,the scheme has low overhead and good robustness.The theoretical EE is also derived for performance evaluation,and simulation result shows the validity of the theoretical analysis.Moreover,EE can be enhanced by decreasing the estimation error and/or path loss exponents. 展开更多
关键词 distributed antenna system energy efficiency adaptive power allocation imperfect channel state information antenna selection
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LOW ENERGY PATHS AND REORIENTATION OF SIDE-GROUPS OF POLYMERS DURING CONFORMATIONAL STATE TRANSITION
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作者 Xiao Zhen YANG Li Ling HE +1 位作者 Bao Zhu AN De Zhu MA Polymer Physics Laboratory, Academia Sinica. Beijing 100080 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第7期631-634,共4页
INTRODUCTION The conformational state transition of polymer chains relates to crystallization processes, migration ofthe chains in solution, fluctuation of the end-to-end distance of random coils, and the relaxation a... INTRODUCTION The conformational state transition of polymer chains relates to crystallization processes, migration ofthe chains in solution, fluctuation of the end-to-end distance of random coils, and the relaxation and phasetransitions of polymers. A description of the conformational state transition requires questions about; 1) howmany stable conformational states for a specific σ bond; 2) the barriers between the states; 3) the mechanismof the conformational transition; 4) any cooperative behavior during the transition. Flory and his coworkers 展开更多
关键词 LOW energy PATHS AND REORIENTATION OF SIDE-GROUPS OF POLYMERS DURING CONFORMATIONAL state TRANSITION
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Using Artificial Neural Networks for Energy Regulation Based Variable-speed Electrohydraulic Drive 被引量:3
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作者 XU Ming JIN Bo +2 位作者 YU Yaxin SHEN Haikuo LI Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第3期327-335,共9页
In the energy regulation based varibable-speed electrohydraulic drive system, the supply energy and the demanded energy, which will affect the control performance greatly, are crucial. However, they are hard to be obt... In the energy regulation based varibable-speed electrohydraulic drive system, the supply energy and the demanded energy, which will affect the control performance greatly, are crucial. However, they are hard to be obtained via conventional methods for some reasons. This paper tries to a new route: the definitive numerical values of the supply energy and the demanded energy are not required, except for their relationship which is called energy state. A three-layer back propagation(BP) neural network was built up to act as an energy analysis unit to deduce the energy state. The neural network has three inputs: the reference displacement, the actual displacement of cylinder rod and the system flowrate supply. The output of the neural network is energy state. A Chebyshev type II filter was designed to calculate the cylinder speed for the estimation of system flowrate supply. The training and testing samples of neural network were collected by the system accurate simulation model. After off-line training, the neural network was tested by the testing data. And the testing result demonstrates that the designed neural network was successful. Then, the neural network acts as the energy analysis unit in real-time experiments of cylinder position control, where it works efficiently under square-wave and sine-wave reference displacement. The experimental results validate its feasibility and adaptability. Only a position sensor and some pressure sensors, which are cheap and have quick dynamic response, are necessary for the system control. And the neural network plays the role of identifying the energy state. 展开更多
关键词 neural network energy state energy regulation device variable-speed
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Pressure influence on the Stark effect of impurity states in a strained wurtzite GaN/Al_xGa_(1-x)N heterojunction 被引量:4
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作者 张敏 班士良 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4449-4455,共7页
A variational method is adopted to investigate the properties of shallow impurity states near the interface in a free strained wurtzite GaN/AlxGa1-xN heterojunction under hydrostatic pressure and external electric fie... A variational method is adopted to investigate the properties of shallow impurity states near the interface in a free strained wurtzite GaN/AlxGa1-xN heterojunction under hydrostatic pressure and external electric field by using a simplified coherent potential approximation. Considering the biaxial strain due to lattice mismatch or epitaxial growth and the uniaxial strains effects, we investigated the Stark energy shift led by an external electric field for impurity states as functions of pressure as well as the impurity position, A1 component and areal electron density. The numerical result shows that the binding energy near linearly increases with pressure from 0 to 10 GPa. It is also found that the binding energy as a function of the electric field perpendicular to the interface shows an un-linear red shift or a blue shift for different impurity positions. The effect of increasing x on blue shift is more significant than that on the red shift for the impurity in the channel near the interface. The pressure influence on the Stark shift is more obvious with increase of electric field and the distance between an impurity and the interface. The increase of pressure decreases the blue shift but increases the red shift. 展开更多
关键词 GAN/ALXGA1-XN strain PRESSURE Stark effect binding energy of impurity state
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Dark energy from logarithmically modified gravity and deformed Coleman-Weinberg potential 被引量:1
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作者 Ahmad Rami El-Nabulsi 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2011年第7期759-766,共8页
Recent astrophysical measurements strongly suggest the existence of a missing energy component dubbed dark energy that is responsible for the current accelerated expansion of the universe.A new class of modified gravi... Recent astrophysical measurements strongly suggest the existence of a missing energy component dubbed dark energy that is responsible for the current accelerated expansion of the universe.A new class of modified gravity theory is introduced which yields a universe accelerating in time and dominated by dark energy.The new modified gravity model constructed here concurrently includes a Gauss-Bonnet invariant term,barotropic fluid with a time-dependent equation of state parameter,a Coleman-Weinberg(CW) potential-like expression V(φ) =ξφm lnφn and a new Einstein-Hilbert term f(R,φ) =E(φ) R which depends on both the scalar curvature and the scalar fieldφthrough a generic logarithmic function E(φ) =lnφ.Here m and n take different values from the standard CW potential andξis a real parameter. It was shown that the presence of these terms provides many useful features which are discussed in some detail. 展开更多
关键词 dark energy—gravitation—equation of state
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The Calculation of Ground State Energies of Double-Electron Systems in an Uniform Magnetic Field below 10~9 G
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作者 Wu Liangkai Liu Lianjun Zhang Zhehua 《Wuhan University Journal of Natural Sciences》 CAS 1999年第1期51-55,共5页
Energies for the ground states of double electron systems in a uniform magnetic field B≤ 10 9 G are calculated by using the modified Slater basis and configuration interaction method, and the result for energy i... Energies for the ground states of double electron systems in a uniform magnetic field B≤ 10 9 G are calculated by using the modified Slater basis and configuration interaction method, and the result for energy in zero magnetic field is comparable with those obtained by different methods. 展开更多
关键词 double electron system MCI method magnetic field ground state energy
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Real-Code Genetic Algorithm for Ground State Energies of Hydrogenic Donors in GaAs-(Ga,Al)As Quantum Dots
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作者 YAN Hai-Qing TANG Chen +1 位作者 LIU Ming ZHANG Hao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期727-730,共4页
We present a global optimization method, called the real-code genetic algorithm (RGA), to the ground state energies. The proposed method does not require partial derivatives with respect to each variational parameter ... We present a global optimization method, called the real-code genetic algorithm (RGA), to the ground state energies. The proposed method does not require partial derivatives with respect to each variational parameter or solving an eigenequation, so the present method overcomes the major difficulties of the variational method. RGAs also do not require coding and encoding procedures, so the computation time and complexity are reduced. The ground state energies of hydrogenic donors in GaAs-(Ga,Al)As quantum dots have been calculated for a range of the radius of the quantum dot radii of practical interest. They are compared with those obtained by the variational method. The results obtained demonstrate the proposed method is simple, accurate, and easy implement. 展开更多
关键词 ground state energy quantum dots real-code genetic algorithms
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Approximate Bound State Solutions for Certain Molecular Potentials
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作者 Mahmoud Farout Mohammed Yasin Sameer M. Ikhdair 《Journal of Applied Mathematics and Physics》 2021年第4期736-750,共15页
We present solutions of the Schrodinger equation with superposition of Manning-Rosen plus inversely Mobius square plus quadratic Yukawa potentials using parametric Nikiforov Uvarov method along with an approximation t... We present solutions of the Schrodinger equation with superposition of Manning-Rosen plus inversely Mobius square plus quadratic Yukawa potentials using parametric Nikiforov Uvarov method along with an approximation to the centrifugal term. The bound state energy eigenvalues for any angular momentum quantum number <em>l</em> and the corresponding un-normalized wave functions are calculated. The mixed potential which in some particular cases gives the solutions for different potentials: the Manning-Rosen, the Mobius square, the inversely quadratic Yukawa and the Hulthén potentials along with their bound state energies are obtained. 展开更多
关键词 Schrödinger Equation Mobius Potential Manning-Rosen Potential Quadratic Yukawa Potential Hulthén Potential Bound state Energies Wave Functions
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Photoelectron angular distributions of H ionization in low energy regime:Comparison between different potentials
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作者 宋舒娜 梁昊 +1 位作者 彭良友 蒋红兵 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期296-302,共7页
We theoretically investigate the low energy part of the photoelectron spectra in the tunneling ionization regime by numerically solving the time-dependent Schrdinger equation for different atomic potentials at various... We theoretically investigate the low energy part of the photoelectron spectra in the tunneling ionization regime by numerically solving the time-dependent Schrdinger equation for different atomic potentials at various wavelengths.We find that the shift of the first above-threshold ionization(ATI) peak is closely related to the interferences between electron wave packets,which are controlled by the laser field and largely independent of the potential.By gradually changing the short-range potential to the long-range Coulomb potential,we show that the long-range potential's effect is mainly to focus the electrons along the laser's polarization and to generate the spider structure by enhancing the rescattering process with the parent ion.In addition,we find that the intermediate transitions and the Rydberg states have important influences on the number and the shape of the lobes near the threshold. 展开更多
关键词 low energy tunneling ionization Coulomb potential Rydberg states
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Conservation of Energy in Classical Mechanics and Its Lack from the Point of View of Quantum Theory
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2016年第16期2316-2328,共13页
It is pointed out that the property of a constant energy characteristic for the circular motions of macroscopic bodies in classical mechanics does not hold when the quantum conditions for the motion are applied. This ... It is pointed out that the property of a constant energy characteristic for the circular motions of macroscopic bodies in classical mechanics does not hold when the quantum conditions for the motion are applied. This is so because any macroscopic body—lo-cated in a high-energy quantum state—is in practice forced to change this state to a state having a lower energy. The rate of the energy decrease is usually extremely small which makes its effect uneasy to detect in course of the observations, or experiments. The energy of the harmonic oscillator is thoroughly examined as an example. Here our point is that not only the energy, but also the oscillator amplitude which depends on energy, are changing with time. In result, no constant positions of the turning points of the oscillator can be specified;consequently the well-known variational procedure concerning the calculation of the action function and its properties cannot be applied. 展开更多
关键词 Classical Mechanics and Conservation of energy Motion Quantization of Macroscopic Bodies energy and Time of Transitions between Quantum states Harmonic Oscillator Taken as an Example
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Influence of the Electric Field on the Properties of the Bound Magnetopolaron in GaAs Semiconductor Quantum Wells 被引量:3
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作者 单淑萍 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第3期438-441,共4页
The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformati... The influence of the electric field on the properties of the bound magnetopolaron in an infinite-depth GaAs semiconductor quantum well is investigated using the linear-combination operator and the unitary transformation method. The relationships between the polaron's ground state energy and the Coulomb bound potential, electric field, magnetic field, and well-width are derived and discussed. Our numerical results show that the absolute value of the polaron's ground state energy increases as the electric field and the Coulomb bound potential increase, and decreases as the well-width and the magnetic field strength increase. When the well-width is small,the quantum size effect is significant. 展开更多
关键词 quantum well bound magnetopolaron linear combination operator ground state energy
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Influence of the Interaction Between Phonons and Coulomb Potential on the Properties of a Bound Polaron in a Quantum Dot
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作者 尹辑文 于毅夫 肖景林 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1883-1887,共5页
The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combinati... The properties of a bound polaron in a parabolic quantum dot with weak electron-LO-phonon coupling under a Coulomb field are studied. The ground state energy of the bound polaron is derived by using a linear combination operator and the perturbation method. The influence of the interaction between phonons with different wave vectors in the recoil process on the ground state energy of the bound polaron is discussed. Numerical calculations are performed,and the results show that the ground state energy increases significantly as the effective confinement length of the quantum dot decreases,considering of the interaction between phonons. When l0〉1.0, the influence of the interaction between phonons on the ground state energy cannot be ignored. 展开更多
关键词 parabolic quantum dot bound polaron interaction between phonons ground state energy
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A Reformulation of Newton Second Law for Charged Particles and Its Application to Quantum Dynamics
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作者 Vu B. Ho 《Journal of Applied Mathematics and Physics》 2021年第11期2796-2806,共11页
We propose a reformulation of Newton’s second law of motion for charged particles and possible applications of the reformulation to quantum dynamics. We show that the negative energy states arising from the Dirac equ... We propose a reformulation of Newton’s second law of motion for charged particles and possible applications of the reformulation to quantum dynamics. We show that the negative energy states arising from the Dirac equation in relativistic quantum mechanics can be verified using the reformulating framework. We also discuss possible hidden dynamics underlying the concept of quantum jumps in quantum mechanics as outlined in Schr<span style="font-size:12px;white-space:nowrap;">&#246;</span>dinger’s article: ARE THERE QUANTUM JUMPS? In this case, we show that the hidden dynamics of quantum jumps are also determined by the Coulomb interaction between charged particles. 展开更多
关键词 Reformulation of Newton Second Law Dirac Negative energy states Quantum Jumps in Quantum Mechanics
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Improved Market Mechanism for Energy Storage Based on Flexible State of Energy 被引量:5
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作者 Dapeng Chen Zhaoxia Jing 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2022年第3期838-848,共11页
In this paper,a new operational mode is proposed for energy storage,in which an improved semi-centralized mechanism is proposed for energy storage to participate in the day-ahead energy market.The new operational mode... In this paper,a new operational mode is proposed for energy storage,in which an improved semi-centralized mechanism is proposed for energy storage to participate in the day-ahead energy market.The new operational mode,i.e.,the flexible state-of-energy(SOE)mode,is proposed based on the previous fixed SOE mode,under which the final SOE of energy storage at the end of the last period of the scheduling horizon is not limited to a predefined value.Accordingly,the value of the SOE is introduced to quantify the deviation cost of the final SOE from the predefined value.Under the proposed market mechanism,energy storage submits to the system operator the unit charging and discharging costs and the value of the SOE.The system operator dispatches the charging and discharging power of energy storage according to the data submitted and system operations.A comparative analysis is conducted in the case studies,and results demonstrate that the proposed mechanism is efficient in further realizing the flexibility potential of energy storage and reducing the total cost of the power system. 展开更多
关键词 energy storage flexible operation mode market mechanism state of energy
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Influence of temperature on ground state energy of bound polaron in asymmetric Gaussian potential quantum well in presence of electromagnetic field 被引量:1
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作者 Ying-Jie Chen Ze-Chen Yan +1 位作者 Kai-Yue Zhang Feng-Lan Shao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第11期121-126,共6页
By a combination method of Lee-Low-Pines unitary transformation method and Pekar-type variational method,the ground state energy(GSE)of the bound polaron is studied in the asymmetrical Gaussian potential quantum well ... By a combination method of Lee-Low-Pines unitary transformation method and Pekar-type variational method,the ground state energy(GSE)of the bound polaron is studied in the asymmetrical Gaussian potential quantum well considering the temperature and electromagneticfield.The impacts of the temperature and asymmetrical Gaussian potential,electromagnetic field and phonon-electron coupling upon the GSE are obtained.The results show that the GSE of the bound polaron not only oscillates as the temperature changes regardless of the electromagneticfield and asymmetrical Gaussian potential and Coulomb impurity potential(CIP)and electron-phonon coupling but also has different rules with the electromagnetic field and asymmetrical Gaussian potential and CIP and electron-phonon coupling at different temperature zones. 展开更多
关键词 asymmetrical Gaussian potential quantum well bound polaron TEMPERATURE ground state energy
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