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Two-state energy model and experimental study of coal adsorb methane 被引量:2
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作者 Zeng-Chao FENG Dong ZHAO Zhi-Xiang LIU Yan-Qi WANG Hong-Qiang GOU 《Journal of Coal Science & Engineering(China)》 2013年第4期488-492,共5页
There are two states of methane existing in coal, free methane and adsorptive methane. The two states of methane exchanged with each other which need the energy exchange with outside. It is released heat when methane ... There are two states of methane existing in coal, free methane and adsorptive methane. The two states of methane exchanged with each other which need the energy exchange with outside. It is released heat when methane adsorption on coal, instead of absorbed heat. According to the gas molecules Boltzmann energy distribution, is obtained the equilibrium equations of the two states of methane in coal, as well as the heat of adsorption equation when exchanged into each other. At the same time, high temperature experiments of methane adsorption on coal have been certificated to the theoretical model. At last the experimental results presented that: the two-state energy model could be accurately described the distribution of the two states of methane in the coal; the adsorption heat is related to the initial equilibrium state of methane adsorption; the adsorption heats are different with different coal ranks. 展开更多
关键词 two-state energy model adsorption heat chemical potential experimental study
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Effective Two-State Model and NOON States for Double-Well Bose-Einstein Condensates in Strong-Interaction Regime 被引量:1
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作者 YANG Xiao-Xue WU Ying 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第8期244-246,共3页
The model of double-well Bose-Einstein condensates in the strong-interaction regime is shown to reduce adiabatically to an effective two-state model describing the Rabi oscillations between the two atomic Fock states ... The model of double-well Bose-Einstein condensates in the strong-interaction regime is shown to reduce adiabatically to an effective two-state model describing the Rabi oscillations between the two atomic Fock states |N, 0〉 and [0, N〉, and the NOON states of arbitrary ultracold atoms can therefore be generated periodically from the initial state of either one of the Foek states. 展开更多
关键词 double-well Bose-Einstein condensates effective two-state model NOON states
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Large Signal Modulation Characteristics in the Transition Regime for Two-State Lasing Quantum Dot Lasers
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作者 吕尊仁 季海铭 +4 位作者 杨晓光 罗帅 高凤 许锋 杨涛 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第12期63-67,共5页
Large-signal modulation capability, as an important performance indicator, is directly related to the high-speed optical communication technology involved. We experimentally and theoretically investigate the large-sig... Large-signal modulation capability, as an important performance indicator, is directly related to the high-speed optical communication technology involved. We experimentally and theoretically investigate the large-signal modulation characteristics of the simultaneous ground-state (GS) and the excited-state (ES) lasing in InAs/OaAs quantum dot laser diodes. The large-signal modulation capability of total light intensity in the transition regime from OS lasing to two-state lasing is unchanged as the bias-current increases. However, GS and ES large-signal eye diagrams show obvious variations during the transition. Relaxation oscillations and large-signal eye diagrams for OS, ES, and total light intensities are numerically simulated and analyzed in detail by using a rate-equation model. The -ndings show that a complementary relationship between the light intensities for OS and ES lasing exists in both the transition regime and the two-state lasing regime, leading to a much smaller overshooting power and a shorter settling time for the total light intensity. Therefore, the eye diagrams of GS or ES lasing are diffuse whereas those of total light intensity are constant as the bias-current increases in the transition regime. 展开更多
关键词 GS for Large Signal Modulation Characteristics in the Transition Regime for two-state Lasing Quantum Dot Lasers ES of in
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A Deep Two-State Gated Recurrent Unit for Particulate Matter (PM_(2.5)) Concentration Forecasting
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作者 Muhammad Zulqarnain Rozaida Ghazali +3 位作者 Habib Shah Lokman Hakim Ismail Abdullah Alsheddy Maqsood Mahmud 《Computers, Materials & Continua》 SCIE EI 2022年第5期3051-3068,共18页
Air pollution is a significant problem in modern societies since it has a serious impact on human health and the environment.Particulate Matter(PM_(2.5))is a type of air pollution that contains of interrupted elements... Air pollution is a significant problem in modern societies since it has a serious impact on human health and the environment.Particulate Matter(PM_(2.5))is a type of air pollution that contains of interrupted elements with a diameter less than or equal to 2.5 m.For risk assessment and epidemiological investigations,a better knowledge of the spatiotemporal variation of PM_(2.5) concentration in a constant space-time area is essential.Conventional spatiotemporal interpolation approaches commonly relying on robust presumption by limiting interpolation algorithms to those with explicit and basic mathematical expression,ignoring a plethora of hidden but crucial manipulating aspects.Many advanced deep learning approaches have been proposed to forecast Particulate Matter(PM_(2.5)).Recurrent neural network(RNN)is one of the popular deep learning architectures which is widely employed in PM_(2.5) concentration forecasting.In this research,we proposed a Two-State Gated Recurrent Unit(TS-GRU)for monitoring and estimating the PM_(2.5) concentration forecasting system.The proposed algorithm is capable of considering both spatial and temporal hidden affecting elements spontaneously.We tested our model using data from daily PM_(2.5) dimensions taken in the contactual southeast area of the United States in 2009.In the studies,three evaluation matrices were utilized to compare the overall performance of each algorithm:Mean Absolute Error(MAE),Root Mean Square Error(RMSE),and Mean Absolute Percentage Error(MAPE).The experimental results revealed that our proposed TS-GRU model outperformed compared to the other deep learning approaches in terms of forecasting performance. 展开更多
关键词 Deep learning PM_(2.5)forecasting air pollution two-state GRU
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Einstein Dilemma and Two-State Vector Formalism
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作者 Kunihisa Morita 《Journal of Quantum Information Science》 2015年第2期41-46,共6页
In the famous EPR paper published in 1935, Einstein, Podolsky, and Rosen suggested a thought experiment, which later became known as the “EPR experiment”. Using the EPR experiment, they posited that quantum mechanic... In the famous EPR paper published in 1935, Einstein, Podolsky, and Rosen suggested a thought experiment, which later became known as the “EPR experiment”. Using the EPR experiment, they posited that quantum mechanics was incomplete. Einstein, however, was dissatisfied with the EPR paper and published a second work on the EPR experiment, in which he discussed the dilemma of choosing whether quantum mechanics was incomplete or nonlocal. Currently, most physicists choose the nonlocality of quantum mechanics over Einstein’s choice of the incompleteness of quantum mechanics. However, with an appropriate alternate hypothesis, both of these choices can be rejected. Herein, I demonstrate an approach to overcome the Einstein Dilemma by proposing a new interpretation invoked by a new formalism of quantum mechanics known as two-state vector formalism. 展开更多
关键词 two-state Vector FORMALISM EINSTEIN DILEMMA COMPLETENESS LOCALITY
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Measurement Problem and Two-State Vector Formalism
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作者 Kunihisa Morita 《Journal of Modern Physics》 2015年第13期1864-1867,共4页
In this paper, I show that an interpretation of quantum mechanics using two-state vector formalism proposed by Aharonov, Bergmann, and Lebowitz, can solve one of the measurement problems formulated by Maudlin. Accordi... In this paper, I show that an interpretation of quantum mechanics using two-state vector formalism proposed by Aharonov, Bergmann, and Lebowitz, can solve one of the measurement problems formulated by Maudlin. According to this interpretation, we can simultaneously insist that the wave function of a system is complete, that the wave function is determined by the Schr?dinger equation, and that the measurement of a physical quantity always has determinate outcomes, although Maudlin in his formulation of the measurement problem states that these three claims are mutually inconsistent. Further, I show that my interpretation does not contradict the uncertainty relation and the no-go theorem. 展开更多
关键词 two-state VECTOR FORMALISM Measurement Problem No-Go THEOREM
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Transfer Matrix Approach for Two-State Scattering Problem with Arbitrary Coupling
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作者 Diwaker Aniruddha Chakraborty 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期5-8,共4页
The present work deals with the calculation of transition probability between two diabatic potentials coupled by any arbitrary coupling. The method presented in this work is applicable to any type of coupling while fo... The present work deals with the calculation of transition probability between two diabatic potentials coupled by any arbitrary coupling. The method presented in this work is applicable to any type of coupling while for numerical calculations we have assumed the arbitrary coupling as Gaussian coupling. This arbitrary coupling is expressed as a collection of Dirac delta functions and by the use of the transfer matrix technique the transition probability from one diabatic potential to another diabatic potential is calculated. We examine our approach by considering the case of two constant potentials coupled by Gaussian coupling as an arbitrary coupling. 展开更多
关键词 Transfer Matrix Approach for two-state Scattering Problem with Arbitrary Coupling
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Theoretical Investigation for Two-state Reactivity of CO_2 Hydrogenation Catalyzed by Ru in Gas Phase
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作者 王永成 贾义明 +1 位作者 王文雪 马盼盼 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第12期1819-1828,共10页
Gas-phase CO_2 catalyzed activation hydrogenation by Ru atoms was studied with density functional theory. Based on the structure optimization of different potential energy surfaces,there are two crossing points betwee... Gas-phase CO_2 catalyzed activation hydrogenation by Ru atoms was studied with density functional theory. Based on the structure optimization of different potential energy surfaces,there are two crossing points between singlet and triplet potential energy surfaces and there is a crossing point between quintet and triplet potential energy surfaces in the whole catalytic cycle. Spin transition probabilities in the vicinity of the intersections have been calculated by the Landau-Zener model theory. There are three minimum energy crossing points(MECPs) with strong spin-orbital coupling effect and higher spin transition probability,and all spin inversion occurred in s orbital and different d orbitals of ruthenium,indicating this is a typical two-state reactivity(TSR) reaction. Finally,the lowest energy reaction path is ensured. 展开更多
关键词 two-state reactivity(TSR) carbon dioxide hydrogenation minimum energy crossing point(MECP) transition metal catalyzed intersystem crossing(ISC)
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Low-order harmonic generation of hydrogen molecular ion in laser field studied by the two-state model 被引量:1
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作者 Ling-Ling Du Guo-Li Wang +1 位作者 Peng-Cheng Li Xiao-Xin Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第11期459-465,共7页
The low-order harmonic generation of hydrogen molecular ion interacting with a linearly polarized laser field has been investigated theoretically by using a simple two-state model. The validity of the two-state model ... The low-order harmonic generation of hydrogen molecular ion interacting with a linearly polarized laser field has been investigated theoretically by using a simple two-state model. The validity of the two-state model is carefully examined by comparing the harmonic spectra of hydrogen molecular ion obtained from this model with those from the three-dimensional time-dependent Schr¨odinger equation. When combined with the Morlet transform of quantum time-frequency spectrum,the two-state model can be used to study the dynamical origin of the low-order harmonic generation of hydrogen molecular ion driven by low-frequency pulses. In addition, some interesting structures of the time profiles for low order harmonics are obtained. 展开更多
关键词 low order harmonic generation hydrogen molecule ion two state model
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Theoretical study of spin-orbit coupling and intersystem crossing in the two-state reaction between Nb(NH_2)_3 and N_2O 被引量:1
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作者 LV LingLing WANG XiaoFang +2 位作者 ZHU YuanCheng LIU XinWen WANG-YongCheng 《Science China Chemistry》 SCIE EI CAS 2012年第1期158-166,共9页
The two-state mechanism of the reaction of Nb(NH2)3 with N2O on the singlet and triplet potential energy surfaces has been investigated at the B3LYP level.Crossing points between the potential energy surfaces have bee... The two-state mechanism of the reaction of Nb(NH2)3 with N2O on the singlet and triplet potential energy surfaces has been investigated at the B3LYP level.Crossing points between the potential energy surfaces have been located using different methods.Analysis of the strain model shows that the singlet state of the four-coordinate(N2O)Nb(NH2)3 complex with N2O bonded via terminal N atom coordination(12) is more stable in the initial stage of reaction,since the bending of the N2O fragment [Edef(N2O) = 86.1 kcal mol-1] results in an energy splitting of the doubly degenerate LUMO;the low-energy LUMO can now strongly couple with the occupied Nb-localized d orbitals,forming a back-bond and transferring charge(q = 0.82 e) from Nb(NH2)3 to the N2O ligand.Going from 32 to 12,the reacting system changes spin multiplicity near the MECP(minimal energy crossing point) region,which takes place with a spin crossing barrier of 9.6-10.0 kcal mol-1.Analysis of spin-orbit coupling(SOC) indicates that MECP will produce a significant SOC matrix element.The value of SOC is 111.52 cm-1,due to the electron shift between two perpendicular φ orbitals with the same rotation direction,and the magnitude of the spin-multi-plicity mixing increases in the small energy gap between high-and low-spin states,greatly enhancing the probability of intersystem crossing.The probabilities of single(P1 ISC) and double(P2 ISC) passes estimated at MECP(SOC = 111.52 cm-1) are approximately 1.17×10-2 and 2.32×10-2,respectively. 展开更多
关键词 two-state reaction mechanism spin-orbit coupling(SOC) transition probability
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Theoretical study of spin-orbit coupling and zero-field splitting in the spin-forbidden two-state reaction between cobaltacyclopentadiene and isocyanate
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作者 Lingling L Xiaofang Wang +3 位作者 Yuancheng Zhu Xinwen Liu Kun Yuan Yongcheng Wang 《Chinese Science Bulletin》 SCIE EI CAS 2014年第3期286-296,共11页
The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coup... The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli Hamiltonian.There are two key crossing points along this two-state reaction pathway.The first crossing point—CP2 exists near^1B.The reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing region.Although the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_0.Therefore,its spin-flip efficiency may be lower.The second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of^1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10^(-1),3.32×10^(-1),and 3.38×10^(-1),respectively). 展开更多
关键词 轨道耦合 异氰酸酯 零场分裂 反应机理 自旋 B3LYP 三重态 交叉点
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国有资产改革对自然资源资产“两权”分离的启示与借鉴
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作者 林霖 黄志豪 +4 位作者 康琴 陈丹 张敏 王珂 虞舟鲁 《生态经济》 北大核心 2025年第1期195-200,共6页
我国国有资产管理体制经过了从统一到分散再到统一的改革历程。在此过程中,国务院设立国有资产监督管理委员会,并逐步推动国有资产管理方式从以管企业为主向以管资本为主转变,探索了国有资产所有权与监管权“两权”分离的路径。鉴于自... 我国国有资产管理体制经过了从统一到分散再到统一的改革历程。在此过程中,国务院设立国有资产监督管理委员会,并逐步推动国有资产管理方式从以管企业为主向以管资本为主转变,探索了国有资产所有权与监管权“两权”分离的路径。鉴于自然资源资产管理与国有资产管理存在较强相似性,国有资产投资运营公司在促进国有资产“两权”分离中的关键作用,为自然资源资产所有权与监管权的分离提供了重要启示和借鉴。自然资源资产管理在完成委托代理机制试点后,建议管理方式由“资源管理”逐步转向“资产管理”,授权设立自然资源投资运营公司,以实现自然资源资产“两权”的有效分离,从“自然资源部门—自然资源资产”的二级管理体制转变为“自然资源部门—自然资源投资运营公司—自然资源资产”的三级管理体制,以期为推进自然资源资产的有效监管和资产增值提供改革思路与参考。 展开更多
关键词 国有资产改革 自然资源资产 “两权”分离 投资运营公司
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基于归因理论的双心护理对卒中后抑郁患者的心理状态及生活质量的影响
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作者 张胜男 张翠萍 《中国医药指南》 2025年第2期65-67,共3页
目的分析基于归因理论的双心护理对卒中后抑郁患者的心理状态及生活质量的影响。方法选取2021年2月至2022年9月厦门大学附属中山医院收治的100例卒中后抑郁患者,随机数字表法分入观察组和对照组,各50例,对照组卒中后抑郁患者采用常规护... 目的分析基于归因理论的双心护理对卒中后抑郁患者的心理状态及生活质量的影响。方法选取2021年2月至2022年9月厦门大学附属中山医院收治的100例卒中后抑郁患者,随机数字表法分入观察组和对照组,各50例,对照组卒中后抑郁患者采用常规护理,观察组卒中后抑郁患者实施基于归因理论的双心护理。比较两组卒中后抑郁症患者护理前后睡眠质量、不良心理评分、生活质量改善情况。结果两组护理前睡眠质量水平等相比,差异无统计学意义(P>0.05)。护理后两组卒中后抑郁症患者以上评分均改善(P<0.05)。观察组卒中后抑郁症患者睡眠时间长于对照组,睡眠潜伏期、不良心理评分均低于对照组,睡眠效率、生活质量评分高于对照组(P<0.05)。结论基于归因理论的双心护理能有效改善卒中后抑郁患者的心理状态及生活质量影响,提升患者的睡眠质量。 展开更多
关键词 卒中后抑郁 归因理论 双心护理 心理状态 生活质量
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计及状态量平均超限比的综合能源系统动态能量流双层优化
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作者 程前 张雪霞 《电力自动化设备》 北大核心 2025年第1期76-83,共8页
综合能源系统(IES)的最优动态能量流能够最大限度地减少系统运行成本。针对IES能量流优化过程中状态量的越限现象,引入状态量平均超限比,统一刻画状态变量的超限程度,并建立计及状态量平均超限比的电-气-热IES多目标动态时序能量流模型... 综合能源系统(IES)的最优动态能量流能够最大限度地减少系统运行成本。针对IES能量流优化过程中状态量的越限现象,引入状态量平均超限比,统一刻画状态变量的超限程度,并建立计及状态量平均超限比的电-气-热IES多目标动态时序能量流模型,以解决状态量超限惩罚代价系数选取不当所导致的优化结果偏离可行最优解的问题。为了防止蜜獾算法(HBA)对能量流的优化陷入局部极小值,建立一种基于多目标差分进化(MODE)算法的双层动态能量流优化模型,上层稳态能量流模型以IES运行成本和状态量平均超限比为优化目标,采用MODE算法求解全局空间内的Pareto非支配解集;下层动态能量流模型以IES运行成本和状态量平均超限惩罚成本的加权和为优化目标,基于Pareto解集生成HBA的初始种群决策量,通过HBA加快求解IES全局最优动态能量流的速度。通过算例仿真验证了所提模型和优化方法的有效性。 展开更多
关键词 综合能源系统 状态量平均超限比 动态能量流 双层优化模型 蜜獾算法 多目标差分进化算法
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A Two-Station Passive Locating Solution Independent of the Baseline Length 被引量:1
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作者 Tao Yu 《Open Journal of Applied Sciences》 2020年第7期476-485,共10页
The two-station positioning system based on time difference and azimuth measurement has measurement redundancy. Therefore, not only can a positioning solution which is completely independent of the baseline length bet... The two-station positioning system based on time difference and azimuth measurement has measurement redundancy. Therefore, not only can a positioning solution which is completely independent of the baseline length between two stations be derived, but also the baseline length can be solved as an unknown quantity. These findings not only enhance the performance of the two-station positioning system, but also provide a design basis for the construction of a self-organizing dynamic intelligent positioning system. 展开更多
关键词 Positioning without Baseline two-station Locating Time Difference Direction Finding Path Difference Passive Location Self-Organizing System
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一种动态锁定式多星协同任务规划的A2C算法
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作者 张晋 赵雪婷 李博文 《宇航学报》 EI CAS CSCD 北大核心 2024年第5期700-710,共11页
提出了一种基于强化学习算法的多星协同任务规划方法。该方法将多星协同任务规划视为多个双星协同规划,采用相邻双星锁定的方式来共享双星任务规划结果信息,基于A2C(优势动作评价)强化学习算法对双星任务规划的结果进行再调整。针对多... 提出了一种基于强化学习算法的多星协同任务规划方法。该方法将多星协同任务规划视为多个双星协同规划,采用相邻双星锁定的方式来共享双星任务规划结果信息,基于A2C(优势动作评价)强化学习算法对双星任务规划的结果进行再调整。针对多星协同任务规划状态空间复杂且变化的问题,设计了两级状态空间和价值评价函数决策的方法,对强化学习所依赖的状态空间进行维度限制,确保智能体对任务进行调整的过程不影响状态空间维度。算法设计过程考虑了多种约束条件,设置了天气、成像质量和成像优先级等可调参数作为强化学习A2C算法的评价参数,这些可调参数有助于用户自定义决策评价体系。最后,通过仿真验证了算法的可行性。仿真结果表明,该算法多星协同任务规划的组合任务抛弃率小于10%。 展开更多
关键词 多星协同任务规划 双星锁定 任务调整 两级状态空间 强化学习
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表面电荷密度及介电常数对AlGaN/GaN异质结中二维电子气性质的影响
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作者 王庆武 于白茹 郭华忠 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期178-184,共7页
通过在Al_(x)Ga_(1-x)N层引入离化电荷面密度,结合自发极化和压电极化引起的极化电荷面密度,利用变分法计算二维电子气面密度随Al组分和Al_(x)Ga_(1-x)N厚度的变化关系.研究了相对介电常数对电子气密度的影响,并与实验数据进行了比较.... 通过在Al_(x)Ga_(1-x)N层引入离化电荷面密度,结合自发极化和压电极化引起的极化电荷面密度,利用变分法计算二维电子气面密度随Al组分和Al_(x)Ga_(1-x)N厚度的变化关系.研究了相对介电常数对电子气密度的影响,并与实验数据进行了比较.通过在Al_(x)Ga_(1-x)N的相对介电常量中引入高阶项,使得计算结果更好地拟合了高Al组分的电子气密度.计算得到的离化电荷面电荷密度与极化电荷面电荷密度相当,从而证明离化面电荷密度对二维电子气形成的贡献. 展开更多
关键词 ALGAN/GAN异质结 二维电子气 离化态 变分法
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使用二态测试的铁磁磨粒质量浓度检测方法
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作者 梁寒钰 魏海军 +2 位作者 何磊 谢飞 付柄春 《振动.测试与诊断》 EI CSCD 北大核心 2024年第6期1167-1172,1248,1249,共8页
现有油液铁磁磨粒检测技术中,使用旋转式PQ仪只能单一检测铁磁性磨损颗粒无量纲指数,使用插入式铁量仪只能单一检测铁磁磨粒浓度,并且检测精度较低。针对此问题,基于旋转式PQ仪设备对样品2种不同状态进行了测试,通过指数计算与系数拟合... 现有油液铁磁磨粒检测技术中,使用旋转式PQ仪只能单一检测铁磁性磨损颗粒无量纲指数,使用插入式铁量仪只能单一检测铁磁磨粒浓度,并且检测精度较低。针对此问题,基于旋转式PQ仪设备对样品2种不同状态进行了测试,通过指数计算与系数拟合,建立起将PQ指数换算成铁磁性磨粒浓度的数学模型。研究结果表明:该拟合方法对大于10μm的铁磁性磨粒有较高的精度,在这一范围内检测值与油液中铁磁磨粒含量实际值相对误差在±8%以内;使用该方法可以同时分析油液中铁磁磨粒PQ指数与质量浓度,能够更有效地判断机械设备中的摩擦磨损状况并优化大尺寸磨粒分析。 展开更多
关键词 铁磁磨粒测量仪 润滑油 PQ指数 质量浓度 二态测试
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基于荷电状态一致性的电池组双层动态均衡方法
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作者 颜宁 张骞 +1 位作者 李相俊 马少华 《高电压技术》 EI CAS CSCD 北大核心 2024年第6期2410-2423,共14页
针对储能系统中电池组充放电过程中能量利用率以及系统运行安全性较低的问题,提出考虑SOC一致性的电池组双层动态均衡方法。首先,采用耦合电感与Flyback变换器搭建均衡系统双层架构,建立电池组端电压、均衡电流及占空比间的关联特性。... 针对储能系统中电池组充放电过程中能量利用率以及系统运行安全性较低的问题,提出考虑SOC一致性的电池组双层动态均衡方法。首先,采用耦合电感与Flyback变换器搭建均衡系统双层架构,建立电池组端电压、均衡电流及占空比间的关联特性。为提高电池组的供能可靠性,系统引入故障切除功能,通过改变开关阵列导通状态实现故障电池组的快速切除;其次,考虑增补电池组剩余容量较大问题,利用传统最值法改进的双层极值法,以荷电状态(stage of charge,SOC)作为均衡目标变量,对增补电池组进行快速放电均衡;最后,设计充放电及静置均衡实验,对比传统最值法,分析常态及故障切除后电路的均衡速度与均衡效率。结果表明,提出的双层均衡方法可以将均衡速度提升约10%,且故障切除后电路的均衡效率最高可达95%以上。 展开更多
关键词 电池组 荷电状态 耦合电感 故障切除 双层均衡 安全性
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二态量子系统准确布居动力学的一类新型相空间表示及其与三角窗函数的关系
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作者 程祥松 贺鑫 刘剑 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期230-254,I0102,共26页
二态系统是最简单的且无经典对应的量子系统,对二态系统的同构表示的认识和研究能启发研究人员对其动力学与统计行为的更深刻理解.本文使用在[J.Chem.Phys.145,204105(2016);J.Chem.Phys.151,024105(2019);J.Phys.Chem.Lett.12,2496(202... 二态系统是最简单的且无经典对应的量子系统,对二态系统的同构表示的认识和研究能启发研究人员对其动力学与统计行为的更深刻理解.本文使用在[J.Chem.Phys.145,204105(2016);J.Chem.Phys.151,024105(2019);J.Phys.Chem.Lett.12,2496(2021)]等文章中发展的约束相空间严格理论、非协变相空间函数、含时权重函数与含时归一化因子来构建一类新型量子相空间表示.这类同构表示可以导出二态量子系统布居动力学的准确结果.约束相空间上的轨迹运动方程同构于含时薛定谔方程.每条相空间轨迹对于布居动力学所对应积分表达式的贡献严格半正定。进一步证明了在[J.Chem.Phys.145,144108(2016)]这篇文章中根据经验提出的三角窗函数方法在本质上可以对应于本文的这类新型相空间表示的一个特殊情况,因此同样是二态量子系统准确布居动力学的同构表示. 展开更多
关键词 相空间表示 约束相空间 有限态量子系统 二态系统 布居动力学
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