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Ab initio potential energy surface and anharmonic vibration spectrum of NF_(3)^(+)
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作者 陈艳南 徐建刚 +3 位作者 范江鹏 马双雄 郭甜 张云光 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期327-333,共7页
Potential energy surfaces(PESs), vibrational frequencies, and infrared spectra are calculated for NF_(3)^(+) using ab initio calculations, based on UCCSD(T)/cc-p VTZ combined with vibrational configuration interaction... Potential energy surfaces(PESs), vibrational frequencies, and infrared spectra are calculated for NF_(3)^(+) using ab initio calculations, based on UCCSD(T)/cc-p VTZ combined with vibrational configuration interaction(VCI). Based on an iterative algorithm, the surfaces(SURF) program adds automatic points to the lattice representation of the potential function, the one-dimensional and two-dimensional PESs are calculated after reaching a convergence threshold, finally the smooth image of the potential energy surface is fitted. The PESs accurately account for the interaction between the different modes, with the mode q_(6) symmetrical stretching vibrations having the greatest effect on the potential energy change of the whole system throughout the potential energy surface shift. The anharmonic frequencies are obtained when the VCI matrix is diagonalized. Fundamental frequencies, overtones, and combination bands of NF_(3)^(+) are calculated, which generate the degenerate phenomenon between their frequencies. Finally, the calculated anharmonic frequency is used to plot the infrared spectra.Modal antisymmetric stretching ν_(5) and symmetric stretching ν_(6) exhibit a phenomenon of large-intensity borrowing. This study can provide data to support the characterization in the laboratory. 展开更多
关键词 ab initio methods potential energy surfaces vibration frequencies coupled resonance infrared spectra
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Properties of radiation defects and threshold energy of displacement in zirconium hydride obtained by new deep-learning potential
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作者 王玺 唐孟 +3 位作者 蒋明璇 陈阳春 刘智骁 邓辉球 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期456-465,共10页
Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of dis... Zirconium hydride(ZrH_(2)) is an ideal neutron moderator material. However, radiation effect significantly changes its properties, which affect its behavior and the lifespan of the reactor. The threshold energy of displacement is an important quantity of the number of radiation defects produced, which helps us to predict the evolution of radiation defects in ZrH_(2).Molecular dynamics(MD) and ab initio molecular dynamics(AIMD) are two main methods of calculating the threshold energy of displacement. The MD simulations with empirical potentials often cannot accurately depict the transitional states that lattice atoms must surpass to reach an interstitial state. Additionally, the AIMD method is unable to perform largescale calculation, which poses a computational challenge beyond the simulation range of density functional theory. Machine learning potentials are renowned for their high accuracy and efficiency, making them an increasingly preferred choice for molecular dynamics simulations. In this work, we develop an accurate potential energy model for the ZrH_(2) system by using the deep-potential(DP) method. The DP model has a high degree of agreement with first-principles calculations for the typical defect energy and mechanical properties of the ZrH_(2) system, including the basic bulk properties, formation energy of point defects, as well as diffusion behavior of hydrogen and zirconium. By integrating the DP model with Ziegler–Biersack–Littmark(ZBL) potential, we can predict the threshold energy of displacement of zirconium and hydrogen in ε-ZrH_(2). 展开更多
关键词 zirconium hydride deep learning potential radiation defects molecular dynamics threshold energy of displacement
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Cooperative activation of sodium channels for downgrading the energy efficiency in neuronal information processing
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作者 严浩然 颜家琦 +1 位作者 俞连春 邵玉峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期758-763,共6页
The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel a... The Hodgkin–Huxley model assumes independent ion channel activation,although mutual interactions are common in biological systems.This raises the problem why neurons would favor independent over cooperative channel activation.In this study,we evaluate how cooperative activation of sodium channels affects the neuron’s information processing and energy consumption.Simulations of the stochastic Hodgkin–Huxley model with cooperative activation of sodium channels show that,while cooperative activation enhances neuronal information processing capacity,it greatly increases the neuron’s energy consumption.As a result,cooperative activation of sodium channel degrades the energy efficiency for neuronal information processing.This discovery improves our understanding of the design principles for neural systems,and may provide insights into future designs of the neuromorphic computing devices as well as systematic understanding of pathological mechanisms for neural diseases. 展开更多
关键词 energy efficiency ion channel noise action potential generation neuronal dynamics
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Molecular Dynamics, Diffusion Coefficients and Activation Energy of the Electrolyte (Anode) in Lithium (Li and Li+), Sodium (Na and Na+) and Potassium (K and K+)
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作者 Alain Second Dzabana Honguelet Timothée Nsongo +1 位作者 Bitho Rodongo Earvin Loumbandzila 《Modeling and Numerical Simulation of Material Science》 2024年第1期39-57,共19页
This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studi... This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studied;with and without gap. In this work, we present the structural, physical and chemical properties of the lithium, sodium and potassium electrodes. For the structural properties, the cohesive energy and the mesh parameters were calculated, revealing that, whatever the chemical element selected, the compact hexagonal hcp structure is the most stable, followed by the face-centred cubic CFC structure, and finally the BCC structure. The most stable structure is lithium, with a cohesion energy of -6570 eV, and the lowest bcc-hcp transition energy of -0.553 eV/atom, followed by sodium. For physical properties, kinetic and potential energies were calculated for each of the sectioned chemical elements, with lithium achieving the highest value. Finally, for the chemical properties, we studied the diffusion coefficient and the activation energy. Only potassium followed an opposite order to the other two, with the quantities with lacunae being greater than those without lacunae, whatever the multiplicity. The order of magnitude of the diffusion coefficients is given by the relationship D<sub>Li</sub> > D<sub>Na</sub> > D<sub>k</sub> for the multiplicity 6*6*6, while for the activation energy the order is reversed. 展开更多
关键词 Molecular Dynamics Diffusion Coefficients activation energy LITHIUM alkali Metals MEaM potential
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Geological reservoir and resource potential(10^(13)m^(3))of gas hydrates in the South China Sea
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作者 Pi-bo Su Wei Wei +5 位作者 Yun-bao Sun Yao-yao Lü Huai Cheng Wei-feng Han Wei Zhang Jin-qiang Liang 《China Geology》 CAS CSCD 2024年第3期422-444,共23页
A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this ... A detailed understanding of the distribution and potential of natural gas hydrate(NGHs)resources is crucial to fostering the industrialization of those resources in the South China Sea,where NGHs are abundant.In this study,this study analyzed the applicability of resource evaluation methods,including the volumetric,genesis,and analogy methods,and estimated NGHs resource potential in the South China Sea by using scientific resource evaluation methods based on the factors controlling the geological accumulation and the reservoir characteristics of NGHs.Furthermore,this study compared the evaluation results of NGHs resource evaluations in representative worldwise sea areas via rational analysis.The results of this study are as follows:(1)The gas hydrate accumulation in the South China Sea is characterized by multiple sources of gas supply,multi-channel migration,and extensive accumulation,which are significantly different from those of oil and gas and other unconventional resources.(2)The evaluation of gas hydrate resources in the South China Sea is a highly targeted,stratified,and multidisciplinary evaluation of geological resources under the framework of a multi-type gas hydrate resource evaluation system and focuses on the comprehensive utilization of multi-source heterogeneous data.(3)Global NGHs resources is n×10^(15)m^(3),while the NGHs resources in the South China Sea are estimated to be 10^(13)m^(3),which is comparable to the abundance of typical marine NGHs deposits in other parts of the world.In the South China Sea,the NGHs resources have a broad prospect and provide a substantial resource base for production tests and industrialization of NGHs. 展开更多
关键词 Reservoir characteristics Natural gas hydrates Gas migration Resource potential Resource evaluation methods Hierarchical evaluation system Volumetric method South China Sea Clean energy exploration engineering
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The Magnetic Longitudinal (P-) Wave’s Propagation and Energy Models Underlying the Mechanisms of Its Capacity to Absorb Free Energy
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作者 Jianzhong Jiang Yufeng Wang 《Journal of Power and Energy Engineering》 2024年第7期39-62,共24页
The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagn... The longitudinal wave term within Faraday’s law of electromagnetic induction (Faraday’s law) underwent recovery to ensure its suitability for theoretical derivation of the equation governing longitudinal electromagnetic (LEM) waves. The revised Maxwell’s equations include the crucial parameters being the attenuation time constants of magnetic vortex potential and electric vortex potential generated by external electromagnetic field within the propagation medium. Specific expressions for them are obtained through theoretical analysis. Subsequently, a model for propagating magnetic P-wave generated by the superposition of a left-handed photo and a right-handed photon in a vacuum is formulated based on reevaluated total current law and revised Faraday’s law, covering wave equations, energy equation, as well as propagation mode involving mutual induction and conversion between scalar magnetic field and vortex electric field. Furthermore, through theoretical derivations centered around magnetic P-wave, evidence was presented regarding its ability to absorb huge free energy through the entangled interaction between zero-point vacuum energy field and the torsion field produced by the vortex electric field. 展开更多
关键词 QED (Quantum Electrodynamics) energy Wave and TEM (Transverse Electromagnetic) Wave Magnetic P-Wave Modified Faraday’s Law of Electromagnetic Induction Electric/Magnetic Vortex potential Zero-Point Vacuum energy
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Research on Potential Energy Recovery System of 16T Wheeled Hybrid Excavator
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作者 SHI Kaikai YUAN Zhonghui 《International Journal of Plant Engineering and Management》 2023年第2期113-122,共10页
The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the re... The system translates the arm/boom/buck's potential energy into electrical energy and then the electrical energy is stored in a storage device.This study develops a set of energy management strategy to make the recoverable energy recycling efficiently.This energy of traditional excavator is lost in the form of heat energy,which is wasteful,and makes the component's temperature higher and higher to reduce the machine's life.Research on this system not only conforms to the current topic of energy crisis,but also mates with the actual engineering,so it is significant to research that. 展开更多
关键词 hybrid excavator potential energy recove aRM energy saving
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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory
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作者 Yang Su Ze-Yu Li +3 位作者 Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期198-207,共10页
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair... Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Pairing force potential energy surfaces Fission fragment distribution
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The Essence of Gravity Is the Expansion Tendency of the Universe after the Big Bang
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作者 Weihong Qian 《Journal of Modern Physics》 2024年第6期804-849,共46页
Why cannot Newton’s theory of gravitation be used to describe the motion of micro particles? This article summarizes and clarifies that Newton’s theory of gravitation is subjectively a statistical description for na... Why cannot Newton’s theory of gravitation be used to describe the motion of micro particles? This article summarizes and clarifies that Newton’s theory of gravitation is subjectively a statistical description for natural phenomena, while its essence is the expansion tendency of particles in the new universe formed after the orthogonal collision (the Big Bang) of objects in the old universe. The new particles formed by the Big Bang exhibit the accelerating expansion and local convergence in the spacetime of the new universe. The force of the accelerating expansion for the new particles comes from the shear stress produced by the orthogonal collision. There is only a one-way conversion from the mass in the old universe to the energy in the new universe without any exchange of information between them. Orthogonal collision forms maximum energy density and accelerates motion of new particles. The theory that orthogonal collision produces a new universe can be used to explain the phenomena of three scales. On the cosmic scale, it can explain the Big Bang, the early celestial formation, and their movements. On the macro scale, it can explain the early Earth’s surface mountain uplift and current atmospheric vortices. At the micro scale, it can explain aurora and other astronomical optical phenomena as well as the generation of new particles. The idea of orthogonal collision attempts to use shear stress and particle potential energy to find a theory of everything that can fully explain all aspects of the universe. 展开更多
关键词 UNIVERSE SPaCETIME GRaVITaTION Orthogonal Collision Shear Stress potential energy
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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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Atomistic Modeling of Lithium Materials from Deep Learning Potential with Ab Initio Accuracy
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作者 Haidi Wang Tao Li +5 位作者 Yufan Yao Xiaofeng Liu Weiduo Zhu Zhao Chen Zhongjun Li Wei Hu 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2023年第5期573-581,I0002,共10页
Lithium has been paid great attention in recent years thanks to its significant appli-cations for battery and lightweight alloy.Developing a potential model with high ac-curacy and efficiency is impor-tant for theoret... Lithium has been paid great attention in recent years thanks to its significant appli-cations for battery and lightweight alloy.Developing a potential model with high ac-curacy and efficiency is impor-tant for theoretical simulation of lithium materials.Here,we build a deep learning potential(DP)for elemental lithium based on a concurrent-learning scheme and DP representation of the density-functional theory(DFT)potential energy surface(PES),the DP model enables material simulations with close-to DFT accuracy but at much lower computational cost.The simulations show that basic parameters,equation of states,elasticity,defects and surface are consistent with the first principles results.More notably,the liquid radial distribution func-tion based on our DP model is found to match well with experiment data.Our results demon-strate that the developed DP model can be used for the simulation of lithium materials. 展开更多
关键词 Deep learning LITHIUM Density functional theory potential energy surface
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Previously Unknown Formulas for the Relativistic Kinetic Energy of an Electron in a Hydrogen Atom
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2023年第4期972-987,共16页
Einstein’s energy-momentum relationship, which holds in an isolated system in free space, contains two formulas for relativistic kinetic energy. Einstein’s relationship is not applicable in a hydrogen atom, where po... Einstein’s energy-momentum relationship, which holds in an isolated system in free space, contains two formulas for relativistic kinetic energy. Einstein’s relationship is not applicable in a hydrogen atom, where potential energy is present. However, a relationship similar to that can be derived. That derived relationship also contains two formulas, for the relativistic kinetic energy of an electron in a hydrogen atom. Furthermore, it is possible to derive a third formula for the relativistic kinetic energy of an electron from that relationship. Next, the paper looks at the fact that the electron has a wave nature. Five more formulas can be derived based on considerations relating to the phase velocity and group velocity of the electron. This paper presents eight formulas for the relativistic kinetic energy of an electron in a hydrogen atom. 展开更多
关键词 Einstein’s energy-Momentum Relationship Relativistic Kinetic energy Bohr’s Quantum Condition potential energy Phase Velocity Group Velocity
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Optimization of Finishing Process and Energy Savings in Denim Textile Facility
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作者 Md. Enamul Haque Kaisul Kabir +5 位作者 Md. Asib Khan Mohammad Abu Syed Nizami Rajib Kabiraj Mohammed Fakhruddin Md. Golam Arif Md. Abu Hanif 《Journal of Textile Science and Technology》 2023年第3期151-164,共14页
Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing ope... Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing operations. So, several treatment processes, including enzymatic, bleaching, singeing, heat set, and ozone finish, are used, which made this processing more energy consumption and time-consuming. Therefore, it is significant to investigate how changing the chemicals and raw ingredients could improve the finishing process, which is environmentally and economically beneficial for sustainable production practices in the denim finishing process. This study’s research design comprises an experimental investigation in a denim plant in Bangladesh. Two different fabrics were chosen to analyze, determining the potential savings of finishing on the denim fabrics’ performance characteristics. By deducting singeing and heat-set processes, the researchers ran an experimental process by maintaining the same length of fabric. Then, the impacts of finishing process optimization on the mechanical, thermal, and comfort parameters of drape, stiffness, and tear strength were examined. The study’s findings demonstrated that this experiment increased productivity and reduced the finishing unit’s energy consumption without compromising the denim fabrics’ quality. This study significantly impacts environmental sustainability by preserving limited energy resources and manufacturing denim finishing processes. 展开更多
关键词 Finishing Process energy Savings Denim Fabrics potential Savings Process Optimization Cotton-Elastane Fabric
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Simulation study of energy resolution with changing pixel size for radon monitor based on Topmetal-Ⅱ^- TPC 被引量:5
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作者 Meng-Yao Huang Hua Pei +1 位作者 Xiang-Ming Sun Shu-Guang Zou 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期49-57,共9页
In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). T... In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). This monitor was designed to improve spatial resolution for detecting radon alpha particles using Topmetal-Ⅱ^- sensors assembled by a 0.35 lm CMOS integrated circuit process.Owing to concerns that small pixel size might have the side effect of worsening energy resolution due to lower signalto-noise ratio, a Geant4-based simulation was used to investigate the dependence of energy resolution on pixel sizes ranging from 60 to 600 lm. A non-monotonic trend in this region shows the combined effect of pixel size and threshold on pixels, analyzed by introducing an empirical expression. Pixel noise contributes 50 keV full-width at half-maximum energy resolution for 400 lm pixel size at 1–4σ threshold that is comparable to the energy resolution caused by energy fluctuations in the TPC ionization process( ~20 keV). The total energy resolution after combining both factors is estimated to be 54 keV for a pixel size of 400 lm at 1–4σ threshold. The analysis presented in this paper would help choosing suitable pixel size for future pixelated detectors. 展开更多
关键词 GEaNT4 energy resolution PIXEL size radon MONITOR Topmetal
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The temporal and spatial patterns and potential evaluation of China's energy resources development 被引量:8
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作者 MA Beibei LU Chunxia +1 位作者 ZHANG Lei CHENG Xiaoling 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期347-356,共10页
The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based... The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based on the notable characteristic of spatial imbalance between energy production and consumption in China, this paper takes the evolution of China's primary energy resources development(excluding hydropower) from 1949 to 2007 as the study object, with the aim to sum up the evolutive characteristics and laws of China's energy resources development in the past nearly 60 years. Then, based on comprehensive considerations of coal's, oil's and natural gas's basic reserves, qualities, geological conditions production status, and ecological service function of every province, this paper adopts development potential index (DP)to evaluate the development potential of every province's en- ergy resources, and divide them into different ranks. Conclusions are drawn as follows: (1) Generally speaking, China's gross energy production was increasing in waves from 1949 to 2007. From the viewpoint of spatial patterns, China's energy resources development has shown a characteristic of "concentrating to the north and central areas, and evolving from linear-shaped to "T-shaped" pattern gradually since 1949. (2) The structure evolution of China's energy resources development in general has shown a trend of "coal proportion is dominant but decreasing, while oil and gas proportions are increasing" since 1949. (3) At the provincial scale, China's energy resources development potential could be divided into large, sub-large, general and small ranks, four in all. In the future, the spatial pattern of China's energy production will evolve from "T-shaped" to "R-shaped pattern". These conclusions will help to clarify the temporal and spatial characteristics and laws of China's energy resources development, and will be beneficial for China to design scientific and rational energy development strategies and plans, coordinate spatial imbalance of energy production and consumption, ensure national energy supply, avoid energy resources waste and disorderly development, and promote regional sustainable development under the globalization back-ground with changeful international energy market. 展开更多
关键词 energy resources development temporal and spatial patterns potential evaluation China
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Ab initio calculations of accurate dissociation energy and analytic potential energy function for the second excited state B^1∏ of ^7LiH 被引量:3
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作者 施德恒 刘玉芳 +2 位作者 孙金锋 朱遵略 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2928-2933,共6页
The reasonable dissociation limit of the second excited singlet state B1∏ of ^7LiH molecule is obtained. The accurate dissociation energy and equilibrium geometry of the B^∏ state are calculated using a symmetry-ada... The reasonable dissociation limit of the second excited singlet state B1∏ of ^7LiH molecule is obtained. The accurate dissociation energy and equilibrium geometry of the B^∏ state are calculated using a symmetry-adaptedcluster configuration interaction method in full active space. The whole potential energy curve for the B1H state is obtained over the internuclear distance ranging from about 0.10 nm to 0,54 nm, and has a least-square fit to the analytic Murrell-Sorbie function form. The vertical excitation energy is calculated from the ground state to the B^1∏ state and compared with previous theoretical results. The equilibrium internuclear distance obtained by geometry optimization is found to be quite different from that obtained by single-point energy scanning under the same calculation condition. Based on the analytic potential energy function, the harmonic frequency value of the B^1∏ state is estimated. A comparison of the theoretical calculations of dissociation energies, equilibrium interatomic distances and the analytic potential energy function with those obtained by previous theoretical results clearly shows that the present work is more comprehensive and in better agreement with experiments than previous theories, thus it is an improvement on previous theories. 展开更多
关键词 ab initio calculation dissociation energy analytic potential energy function
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Structure and analytical potential energy function for the ground state of the BC^x (x=0, -1) 被引量:3
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作者 耿振铎 张岩松 +2 位作者 樊晓伟 路战胜 罗改霞 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1257-1261,共5页
In this paper, the electronic states of the ground states and dissociation limits of BC and BC- are correctly determined based on group theory and atomic and molecular reaction statics. The equilibrium geometries, har... In this paper, the electronic states of the ground states and dissociation limits of BC and BC- are correctly determined based on group theory and atomic and molecular reaction statics. The equilibrium geometries, harmonic frequencies and dissociation energies of the ground state of BC and BC- are calculated by using density function theory and quadratic CI method including single and double substitutions. The analytical potential energy functions of these states have been fitted with Murrell-Sorbie potential energy function from our ab initio calculation results. The spectroscopic data (αe, ωe and ωeχe) of each state is calculated via the relation between analytical potential energy function and spectroscopic data. All the calculations are in good agreement with the experimental data. 展开更多
关键词 ab initio ground state potential energy function
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Accurate potential energy function and spectroscopic study of the X^2Σ^+,A^2Ⅱ and B^2Σ^+ states of the CP radical 被引量:3
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作者 刘玉芳 贾毅 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期170-176,共7页
This paper calculates the equilibrium internuclear separations, the harmonic frequencies and the potential energy curves of the X^2∑+, A^2П and B^2∑+ states of the CP radical by the highly accurate valence intern... This paper calculates the equilibrium internuclear separations, the harmonic frequencies and the potential energy curves of the X^2∑+, A^2П and B^2∑+ states of the CP radical by the highly accurate valence internally contracted multireference configuration interaction method with correlation-consistent basis sets (aug-cc-pV6Z for C atom and aug-cc-pVQZ for P atom). The potential energy curves are all fitted with the analytic potential energy function by the least-square fitting. Employing the analytic potential energy function, we determine the spectroscopic constants (Be, αe and ωeχe) of these states. For the X2∑+ state, the obtained values of De, Be, αe, ωeχe, Re and ωe are 5.4831 eV, 0.792119 cm-1, 0.005521 cm-1, 6.89653 cm-1, 0.15683 nm, 12535.11 cm-1, respectively. For the A2H state, the present values of De, Be,αe, ωeχe, Re and We are 4.586 eV, 0.703333 cm-1, 0.005458 cm-1, 6.03398 cm-1, 0.16613 nm, 1057.89 cm-1, respectively. For the B2E+ state, the present values of De, Be, αe, ωeχe, Re and We are 3.506 eV, 0.677561 cm-1, 0.00603298 cm-1, 5.68809 cm-1, 0.1696 nm, 822.554 cm-1, respectively. For these states, the vibrational states with the rotational quantum number J equals zero (J = 0) are studied by solving the radial nuclear Schr6dinger equation using the Numerov method. For each vibrational state, the vibrational level, the classical turning points, the rotational inertial and the centrifugal distortion constants are calculated. Comparison is made with recent theoretical and experimental results. 展开更多
关键词 multi-reference configuration interaction potential energy curve molecular constant spectroscopic parameter
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Ab initio calculation on accurate analytic potential energy functions and harmonic frequencies of c^3∑g^+ and B^1-Пu states of dimer 7Li2 被引量:2
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作者 余本海 施德恒 +3 位作者 孙金锋 朱遵略 刘玉芳 杨向东 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第8期2371-2377,共7页
The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by ... The comparison between single-point energy scanning (SPES) and geometry optimization (OPT) in determining the equilibrium geometries of c^3∑g^+ and B^1-Пu states of dimer 7Li2 is made at numerous basis sets by using a symmetryadapted-cluster configuration-interaztion (SAC-CI) method in the Gaussian 03 program package. In this paper the difference of the equilibrium geometries obtained by SPES and by OPT is reported. The results obtained by SPES are found to be more reasonable than those obtained by OPT in full active space at the present SAC-CI level of theory. And the conclusion is attained that the cc-PVTZ is a most suitable basis set for these states. The calculated dissociation energies and equilibrium geometries are 0.8818 eV and 0.3090 nm for c^3∑g^+ state, and 0.3668 eV and 0.2932 nm for B^1-Пu state respectively. The potential energy curves are calculated over a wide internuclear distance range from about 2.5α0 to 37α0 and have a least-squares fit into the Murrell-Sorbie function. According to the calculated analytic potential energy functions, the harmonic frequencies (We) and other spectroscopic data (ωeXe, Be and αe) are calculated. Comparison of the theoretical determinations at present work with the experiments and other theories clearly shows that the present work is the most complete effort and thus represents an improvement over previous theoretical results. 展开更多
关键词 molecular structure and potential energy function atomic and molecular collision dimer excited state
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Potential energy curves and analytical potential energy functions of the metastable states of B2^++ 被引量:1
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作者 张晓燕 杨传路 +1 位作者 高峰 任廷琦 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期1981-1986,共6页
The multi-reference configuration interaction method and aug-cc-pvqz (AVQZ) have been used to calculate potential energy curves (PECs) of the singlet and triplet states of the riu and rig symmetry of B2++. All o... The multi-reference configuration interaction method and aug-cc-pvqz (AVQZ) have been used to calculate potential energy curves (PECs) of the singlet and triplet states of the riu and rig symmetry of B2++. All of the four states (^l∏u, ^1∏g, ^3∏u and ^3∏g) are found to be metastable states, though the potential well of ^3∏u symmetry is very shallow. Based on the PECs, the analytical potential energy functions (APEFs) of these states have been fitted using the least square fitting method and two models of function. The spectroscopic parameters of each state are also calculated, and are compared with other investigations in the literature. The credibility and veracity of the two functions are evaluated. Some ideas to improve the fitting accuracy are presented. Also the vibrational levels for each state are predicted by solving the SchrSdinger equation of nuclear motion. 展开更多
关键词 potential energy curves analytical potential energy function spectroscopic parameter metastable state
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