The gyroresonant interaction between electromagnetic ion cyclotron (EMIC) waves and energetic particles was studied in a multi-ion (H^+, He^+, and O^+) plasma. The minimum resonant energy Emin, resonant wave fr...The gyroresonant interaction between electromagnetic ion cyclotron (EMIC) waves and energetic particles was studied in a multi-ion (H^+, He^+, and O^+) plasma. The minimum resonant energy Emin, resonant wave frequency w, and pitch angle diffusion coefficient Daa were calculated at the center location of the symmetrical ring current: r ≈3.5RE with RE the Earth's radius. Emin is found to decrease rapidly from 10 MeV to a few keV with the increase in ca in three bands: H^+-band, He^+-band and O^+-band. Moreover, EMIC waves have substantial potential to scatter energetic (~100 keV) ions (mainly H^+ and He^+) into the loss cone and yield precipitation loss, suggesting that wave-particle interactions contribute to ring current decay.展开更多
Head-on collisions among the single-and multi-soliton’s heavy ion acoustic waves(HIAWs) of multi-ion plasma are studied. The plasma consists of adiabatic positively charged inertial heavy ions, Boltzmann energy distr...Head-on collisions among the single-and multi-soliton’s heavy ion acoustic waves(HIAWs) of multi-ion plasma are studied. The plasma consists of adiabatic positively charged inertial heavy ions, Boltzmann energy distributed light ions and kappa energy distributed electrons. The extended poincaré-Lighthill-Kuo(e PLK) method is applied for the derivation of two-sided Korteweg–de Vries(KdV) equations(KdVEs). The KdV single-soliton solutions(KdVSSs) are determined using the hyperbolic secant method and the KdV multi-soliton solutions(KdVMSs)are obtained using the Hirota method. The effects of superthermality of electrons, temperature ratios of electron to light ion and heavy ion to electron, and the density ratio of electron to heavy ion on phase shifts are investigated for the head-on collisions between two-soliton HIAWs. The effects of plasma parameters on angular frequency, phase speed, production of multi-soliton structures, and the head-on collisions among single-, double-, triple-, quadruple-, and quintuplesolitons are also studied.展开更多
We propose a scheme for generating multi-ion graph states using many trapped ions in thermal motion.Our generation scheme is insensitive to external state since the interaction between ions and laser fields does not i...We propose a scheme for generating multi-ion graph states using many trapped ions in thermal motion.Our generation scheme is insensitive to external state since the interaction between ions and laser fields does not involvethe external degree of freedom.The scheme can be well realized within the current experimental technique.展开更多
The nonlinear propagation of the DIA (dust ion-acoustic) waves in multi-ion dense plasma system containing degener- ate electrons, both positive and negative ions, arbitrary charged dust grains has been investigated b...The nonlinear propagation of the DIA (dust ion-acoustic) waves in multi-ion dense plasma system containing degener- ate electrons, both positive and negative ions, arbitrary charged dust grains has been investigated by employing the reductive perturbation method. The nonlinear waves (solitary and shock waves) have been observed to be formed in case of both positive and negative charged dust grains from the stationary solution of the Korteweg de-Vries (K-dV) equation and Burger’s equation. The fundamental properties of such nonlinear waves have been theoretically analyzed by comparing system potential for both positive and negative dust grains. It has been shown that the basic features of these waves are significantly modified by the positive and negative ions drift speed and polarities of dust grains. The implications of our results in space and laboratory plasmas are briefly discussed.展开更多
利用多组态Dirac-Hartree-Fock方法对类碳等电子序列(Z=10,14,32,36,50)1s^(2)2s^(2)2p^(2)和1s^(2)2s2p^(3)组态的能级结构和电偶极跃迁行为进行理论研究.在构建充分包含电子关联效应、规模适当的波函数后,考虑Breit相互作用、量子电...利用多组态Dirac-Hartree-Fock方法对类碳等电子序列(Z=10,14,32,36,50)1s^(2)2s^(2)2p^(2)和1s^(2)2s2p^(3)组态的能级结构和电偶极跃迁行为进行理论研究.在构建充分包含电子关联效应、规模适当的波函数后,考虑Breit相互作用、量子电动力学效应和原子核质量效应,比较分析了价-价关联效应、实-价关联效应和实-实关联效应对原子态激发能的影响,完成了原子态激发能的高精度理论计算.与其他理论结果相比,本文计算的Ne V离子的激发能结果与NIST(National Institute of Standards and Technology)数据最为接近;其他离子的激发能也具有较好的精度.在此基础上,结合LS耦合的原子态混合成分和NIST数据,对出现的原子态命名情况进行分析,推测了相应的原子态命名.本文还计算了组态间电偶极跃迁的谱线波长、跃迁速率、线强和加权振子强度,Ne V和Si IX离子的谱线波长与NIST数据符合得很好,相对误差小于0.62%;跃迁速率与其他理论结果比较一致.另外,本文计算得到的Babushkin和Coulomb两种规范的电偶极跃迁参数具有良好的一致性,进一步证明了本文采用的理论方法的准确性和可靠性.展开更多
现代金属切削加工正向着高速、高精度和高效的方向发展,对刀具的性能有着越来越高的要求。利用表面技术对刀具表面进行改性,是提高刀具性能和寿命的有效途径。使用多弧离子镀膜技术在YG6硬质合金以及三刃立铣刀表面制备了Cr Al N/CrN/Cr...现代金属切削加工正向着高速、高精度和高效的方向发展,对刀具的性能有着越来越高的要求。利用表面技术对刀具表面进行改性,是提高刀具性能和寿命的有效途径。使用多弧离子镀膜技术在YG6硬质合金以及三刃立铣刀表面制备了Cr Al N/CrN/Cr、TiAlN/CrN/Cr、Cr Al N/TiAlN/CrN/Cr三组涂层,并对三种涂层的制备技术、微观结构与性能差异、及耐磨与切削寿命提高机制进行研究。X射线衍射分析表明,三种涂层均为面心立方结构,其中TiAlN涂层表现出(200)晶面择优取向,而CrAlN和Cr Al N/TiAlN涂层则表现出(111)面的择优取向。使用显微硬度计和划痕仪对涂层的显微硬度和结合力进行测试,结果表明Cr Al N/TiAlN多层涂层的显微硬度和膜基结合力分别为2651 HV和59.2 N,显著高于TiAlN和CrAlN涂层。采用高温摩擦试验机评价了三种涂层的摩擦学性能,结果表明Cr Al N/TiAlN多涂层的摩擦性能优于TiAlN涂层和CrAlN涂层,室温下其平均摩擦因数和磨损率分别为0.603和2.92×10^(-6)mm^(3)(N·m)^(-1)。当温度增加到400℃时,Cr Al N/TiAlN涂层的平均摩擦因数进一步降低为0.467,磨损率增加至1.31×10^(-5)mm^(3)(N·m)^(-1)。铣削试验结果显示,TiAlN涂层刀具、CrAlN涂层刀具和Cr Al N/TiAlN涂层刀具的铣削寿命相对于无涂层刀具分别提升了80%、140%和200%,被加工样件的表面粗糙度分别降低至462 nm、415 nm和402 nm。研究结果表明Cr Al N/TiAlN涂层在现代切削加工领域有着良好的应用潜力。展开更多
锂离子电池健康状态(state of health,SOH)估计对确保能量存储系统的可靠性和安全性至关重要。然而,现有SOH估计方法在单一特征提取和固定充放电条件依赖方面存在局限性,难以适应多变的实际工作环境。为解决这一问题,本工作提出了一种...锂离子电池健康状态(state of health,SOH)估计对确保能量存储系统的可靠性和安全性至关重要。然而,现有SOH估计方法在单一特征提取和固定充放电条件依赖方面存在局限性,难以适应多变的实际工作环境。为解决这一问题,本工作提出了一种基于弛豫电压的并行多尺度特征融合卷积模型(multi-scale feature fusion convolution model,MSFFCM)结合极端梯度提升树(XGBoost)的SOH估计方法。MSFFCM通过多层堆叠卷积模块提取弛豫电压数据的深层特征,同时利用并行多尺度注意力机制增强了多尺度特征的捕捉能力,并将这些特征与统计特征进行融合,以提升模型的特征提取和融合能力。针对XGBoost模型,本工作应用贝叶斯优化算法进行参数调优,从而在多源融合特征基础上实现高精度SOH估计。实验验证基于两种商用18650型号电池的多温度和多充放电策略数据集,结果表明该方法的均方根误差(RMSE)和平均绝对误差(MAE)均小于0.5%,明显优于传统方法。本工作为锂电池健康管理提供了一种不依赖特定充放电条件的有效估计工具,有望在复杂的实际应用中发挥重要作用。展开更多
基金National Natural Science Foundation of China (Nos.40874076,40774078,40774079 and 40536029)the Special Fund for Public Welfare Industry (meteorology)GYHY200806072the Visiting Scholar Foundation of State Key Laboratory for Space Weather,Chinese Academy of Sciences
文摘The gyroresonant interaction between electromagnetic ion cyclotron (EMIC) waves and energetic particles was studied in a multi-ion (H^+, He^+, and O^+) plasma. The minimum resonant energy Emin, resonant wave frequency w, and pitch angle diffusion coefficient Daa were calculated at the center location of the symmetrical ring current: r ≈3.5RE with RE the Earth's radius. Emin is found to decrease rapidly from 10 MeV to a few keV with the increase in ca in three bands: H^+-band, He^+-band and O^+-band. Moreover, EMIC waves have substantial potential to scatter energetic (~100 keV) ions (mainly H^+ and He^+) into the loss cone and yield precipitation loss, suggesting that wave-particle interactions contribute to ring current decay.
文摘Head-on collisions among the single-and multi-soliton’s heavy ion acoustic waves(HIAWs) of multi-ion plasma are studied. The plasma consists of adiabatic positively charged inertial heavy ions, Boltzmann energy distributed light ions and kappa energy distributed electrons. The extended poincaré-Lighthill-Kuo(e PLK) method is applied for the derivation of two-sided Korteweg–de Vries(KdV) equations(KdVEs). The KdV single-soliton solutions(KdVSSs) are determined using the hyperbolic secant method and the KdV multi-soliton solutions(KdVMSs)are obtained using the Hirota method. The effects of superthermality of electrons, temperature ratios of electron to light ion and heavy ion to electron, and the density ratio of electron to heavy ion on phase shifts are investigated for the head-on collisions between two-soliton HIAWs. The effects of plasma parameters on angular frequency, phase speed, production of multi-soliton structures, and the head-on collisions among single-, double-, triple-, quadruple-, and quintuplesolitons are also studied.
基金National Natural Science Foundation of China under Grant Nos.60678022 and 10704001the Specialized Research Fund for the Doctoral Program of Higher Education of Anhui Province under Grant No.20060357008+2 种基金Natural Science Foundation of Anhui Province under Grant No.070412060the Talent Foundation of Anhui UniversityAnhui Key Laboratory of Information Materials and Devices (Anhui University)
文摘We propose a scheme for generating multi-ion graph states using many trapped ions in thermal motion.Our generation scheme is insensitive to external state since the interaction between ions and laser fields does not involvethe external degree of freedom.The scheme can be well realized within the current experimental technique.
文摘The nonlinear propagation of the DIA (dust ion-acoustic) waves in multi-ion dense plasma system containing degener- ate electrons, both positive and negative ions, arbitrary charged dust grains has been investigated by employing the reductive perturbation method. The nonlinear waves (solitary and shock waves) have been observed to be formed in case of both positive and negative charged dust grains from the stationary solution of the Korteweg de-Vries (K-dV) equation and Burger’s equation. The fundamental properties of such nonlinear waves have been theoretically analyzed by comparing system potential for both positive and negative dust grains. It has been shown that the basic features of these waves are significantly modified by the positive and negative ions drift speed and polarities of dust grains. The implications of our results in space and laboratory plasmas are briefly discussed.
文摘利用多组态Dirac-Hartree-Fock方法对类碳等电子序列(Z=10,14,32,36,50)1s^(2)2s^(2)2p^(2)和1s^(2)2s2p^(3)组态的能级结构和电偶极跃迁行为进行理论研究.在构建充分包含电子关联效应、规模适当的波函数后,考虑Breit相互作用、量子电动力学效应和原子核质量效应,比较分析了价-价关联效应、实-价关联效应和实-实关联效应对原子态激发能的影响,完成了原子态激发能的高精度理论计算.与其他理论结果相比,本文计算的Ne V离子的激发能结果与NIST(National Institute of Standards and Technology)数据最为接近;其他离子的激发能也具有较好的精度.在此基础上,结合LS耦合的原子态混合成分和NIST数据,对出现的原子态命名情况进行分析,推测了相应的原子态命名.本文还计算了组态间电偶极跃迁的谱线波长、跃迁速率、线强和加权振子强度,Ne V和Si IX离子的谱线波长与NIST数据符合得很好,相对误差小于0.62%;跃迁速率与其他理论结果比较一致.另外,本文计算得到的Babushkin和Coulomb两种规范的电偶极跃迁参数具有良好的一致性,进一步证明了本文采用的理论方法的准确性和可靠性.
文摘现代金属切削加工正向着高速、高精度和高效的方向发展,对刀具的性能有着越来越高的要求。利用表面技术对刀具表面进行改性,是提高刀具性能和寿命的有效途径。使用多弧离子镀膜技术在YG6硬质合金以及三刃立铣刀表面制备了Cr Al N/CrN/Cr、TiAlN/CrN/Cr、Cr Al N/TiAlN/CrN/Cr三组涂层,并对三种涂层的制备技术、微观结构与性能差异、及耐磨与切削寿命提高机制进行研究。X射线衍射分析表明,三种涂层均为面心立方结构,其中TiAlN涂层表现出(200)晶面择优取向,而CrAlN和Cr Al N/TiAlN涂层则表现出(111)面的择优取向。使用显微硬度计和划痕仪对涂层的显微硬度和结合力进行测试,结果表明Cr Al N/TiAlN多层涂层的显微硬度和膜基结合力分别为2651 HV和59.2 N,显著高于TiAlN和CrAlN涂层。采用高温摩擦试验机评价了三种涂层的摩擦学性能,结果表明Cr Al N/TiAlN多涂层的摩擦性能优于TiAlN涂层和CrAlN涂层,室温下其平均摩擦因数和磨损率分别为0.603和2.92×10^(-6)mm^(3)(N·m)^(-1)。当温度增加到400℃时,Cr Al N/TiAlN涂层的平均摩擦因数进一步降低为0.467,磨损率增加至1.31×10^(-5)mm^(3)(N·m)^(-1)。铣削试验结果显示,TiAlN涂层刀具、CrAlN涂层刀具和Cr Al N/TiAlN涂层刀具的铣削寿命相对于无涂层刀具分别提升了80%、140%和200%,被加工样件的表面粗糙度分别降低至462 nm、415 nm和402 nm。研究结果表明Cr Al N/TiAlN涂层在现代切削加工领域有着良好的应用潜力。