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Sensitive Detection of Individual Neutral Atoms in a Strong Coupling Cavity QED System

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chinese Physics Letters 2011年第4期28卷 101-104页

作者： zhang Peng-Fei zhang yu-chi LI Gang DU Jin-Jin zhang Yan-Feng GUO Yan-Qiang WANG Jun-Min zhang Tian-Cai LI Wei-Dong State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi UniversityTaiyuan 030006 Department of Physics and Institute of Theoretical Physics Shanxi UniversityTaiyuan 030006

We experimentally demonstrate real-time detection of individual cesium atoms by using a high-finesse optical micro-cavity in a strong coupling regime.A cloud of cesium atoms is trapped in a magneto-optical trap positioned at 5mm above the micro-cavity *** atoms fall down freely in gravitation after shutting off the magnetooptical trap and pass through the *** cavity transmission is strongly affected by the atoms in the cavity,which enables the micro-cavity to sense the atoms *** detect the single atom transits either in the resonance or various *** single atom vacuum-Rabi splitting is directly measured to beΩ=2π×23.9 *** average duration of atom-cavity coupling of about 110μs is obtained according to the probability distribution of the atom transits.

关键词： coupling splitting enable

醋酸甲酯-甲醇-水-醋酸四元体系液液相平衡数据的测定与关联

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高校化学工程学报 2013年第3期27卷 380-385页

作者：张于弛邱挺闽江学院化学与化学工程系福建福州350108 福州大学化学化工学院福建福州350108

为获得提高醋酸甲酯催化精馏的水解转化率所需的基础数据,实验在常压下测定了20,30,40,50℃时醋酸甲酯-水-醋酸三元体系和醋酸甲酯-甲醇-水-醋酸四元体系的液液相平衡数据,用NRTL和UNIQUAC模型对所测的数据进行热力学关联,应用单纯形法... 详细信息

为获得提高醋酸甲酯催化精馏的水解转化率所需的基础数据,实验在常压下测定了20,30,40,50℃时醋酸甲酯-水-醋酸三元体系和醋酸甲酯-甲醇-水-醋酸四元体系的液液相平衡数据,用NRTL和UNIQUAC模型对所测的数据进行热力学关联,应用单纯形法得出相应的模型参数。四元体系的计算值与实验值比较结果表明:NRTL与UNIQUAC模型的计算值与实验数据吻合良好,模型计算的总平均绝对误差分别为0.001142和0.001329,总平均相对误差分别为3.025%和3.839%。

关键词：醋酸甲酯-甲醇-水-醋酸液液相平衡 NRTL模型 UNIQUAC模型

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science china Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG Ping GUAN chi zhang Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

湿热环境对碳纳米管复合材料界面应力传递的影响

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工程力学 2006年第8期23卷 172-176页

作者：张宇驰王熙上海交通大学船舶海洋与建筑工程学院上海200240

基于碳纳米管的热膨胀系数及弹性模量分别为温度变化的函数,基体的热、湿膨胀系数及弹性模量分别为温度变化和湿度变化的函数,应用连续介质力学的经典弹性壳理论及传统纤维拉拔模型,分析了湿热环境对碳纳米管复合材料界面应力传递的影... 详细信息

基于碳纳米管的热膨胀系数及弹性模量分别为温度变化的函数,基体的热、湿膨胀系数及弹性模量分别为温度变化和湿度变化的函数,应用连续介质力学的经典弹性壳理论及传统纤维拉拔模型,分析了湿热环境对碳纳米管复合材料界面应力传递的影响。数值计算表明,湿度、温度的效应及碳纳米管的层数等参数对界面应力的传递均有显著影响。

关键词：碳纳米管复合材料界面应力传递湿热环境纤维拉拔膨胀系数

Method for Estimating the State of Health of Lithium-ion Batteries Based on Differential Thermal Voltammetry and Sparrow Search Algorithm-Elman Neural Network

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Energy Engineering 2025年第1期122卷 203-220页

作者： yu zhang Daoyu zhang TiezhouWu School of Electrical and Electronic Engineering Hubei University of TechnologyWuhan430068China

Precisely estimating the state of health(SOH)of lithium-ion batteries is essential for battery management systems(BMS),as it plays a key role in ensuring the safe and reliable operation of battery ***,current SOH estimation methods often overlook the valuable temperature information that can effectively characterize battery aging during capacity ***,the Elman neural network,which is commonly employed for SOH estimation,exhibits several drawbacks,including slow training speed,a tendency to become trapped in local minima,and the initialization of weights and thresholds using pseudo-random numbers,leading to unstable model *** address these issues,this study addresses the challenge of precise and effective SOH detection by proposing a method for estimating the SOH of lithium-ion batteries based on differential thermal voltammetry(DTV)and an SSA-Elman neural ***,two health features(HFs)considering temperature factors and battery voltage are extracted fromthe differential thermal voltammetry curves and incremental capacity ***,the Sparrow Search Algorithm(SSA)is employed to optimize the initial weights and thresholds of the Elman neural network,forming the SSA-Elman neural network *** validate the performance,various neural networks,including the proposed SSA-Elman network,are tested using the Oxford battery aging *** experimental results demonstrate that the method developed in this study achieves superior accuracy and robustness,with a mean absolute error(MAE)of less than 0.9%and a rootmean square error(RMSE)below 1.4%.

关键词： Lithium-ion battery state of health differential thermal voltammetry Sparrow Search Algorithm

Nano high-entropy oxide cathode with enhanced stability for direct borohydride fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 309-316页

作者： Lei zhang Lingfeng Kuang Lianke zhang Wen Chu Haiying Qin Jing zhang Junjing He Hualiang Ni Hongzhong chi New Energy Materials Research Center College of Materials and Environmental Engineering Hangzhou Dianzi University School of Materials Science and Engineering Zhejiang University Key Laboratory of MEMS of Ministry of Education School of Integrated Circuits Southeast University

High-entropy materials have become high-activity electrocatalysis owing to their high-entropy effect and multiple active ***,we synthesize a series of carbon-supported nano high-entropy oxides（HEOs/C）,specifically （PtFeCoNiCu）O/C,using a carbothermal shock （CTS） method for application as a cathode catalyst in direct borohydride fuel cells （DBFCs）.The microstructure of the prepared catalysts was characterized by X-ray photoelectron spectroscopy,X-ray absorption fine structure,and transmission electron *** prepared （PtFeCoNiCu）O/C,with particle sizes ranging from 2 to 4 nm,demonstrates 3.94 transferred electrons towards the oxygen reduction reaction in an alkaline environment,resulting in a minimal H2O2yield of 2.6%.Additionally,it exhibits a Tafel slope of 61 mV dec-1,surpassing that of commercial Pt/C (82 mV dec-1).Furthermore,after 40,000 cycles of cyclic voltammetry（CV） testing,the half-wave potential of （PtFeCoNiCu）O/C shows a positive shift of 3 mV,with no notable decline in the limiting current *** （PtFeCoNiCu）O/C is used as a cathode catalyst in DBFCs,the DBFC achieves a maximum power density of 441 mW cm-2at 60°C and sustains a cell voltage of approximately 0.73 V after 52 h at 30°*** findings confirm that HEO/C is a promising cathode catalyst for DBFCs.

关键词： Direct borohydride fuel cells (DBFC)

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基于乳化炸药生产工艺的流量检测分析

制造业自动化 2012年第1期34卷 50-55页

作者：张字驰湖南工业职业技术学院长沙410208

乳化炸药生产过程的油水相流量控制是连续生产控制中的关键环节，流量控制的性能优劣对提高产品质量、保证生产过程的可靠性、安全性具有非常重要的意义。本文以乳化炸药生产为研究对象，主要介绍了油水相流量给定和检测的分析方法，有... 详细信息

乳化炸药生产过程的油水相流量控制是连续生产控制中的关键环节，流量控制的性能优劣对提高产品质量、保证生产过程的可靠性、安全性具有非常重要的意义。本文以乳化炸药生产为研究对象，主要介绍了油水相流量给定和检测的分析方法，有效的控制了油水相流量的实时添加，实现了乳化炸药的连续化生产。

关键词：乳化炸药流量控制油水相

新工科背景下《聚合物基复合材料》课程改革与实践

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高分子通报 2022年第6期 90-94页

作者：夏建荣张于弛闽江学院材料与化学工程学院福州350108

根据新工科背景下高分子材料与工程专业人才培养的要求。针对《聚合物基复合材料》课程的教学现状,教学团队尝试在教学方法上进行改革。将科研成果融入到聚合物/石墨烯纳米复合材料章节的课堂教学中。通过对科研成果的分析讨论,加深了... 详细信息

根据新工科背景下高分子材料与工程专业人才培养的要求。针对《聚合物基复合材料》课程的教学现状,教学团队尝试在教学方法上进行改革。将科研成果融入到聚合物/石墨烯纳米复合材料章节的课堂教学中。通过对科研成果的分析讨论,加深了学生对复合材料流变性能的理解,搭建了复合材料的内部微观结构与外部性能之间的桥梁,为复合材料的成型工艺提供了理论指导。通过实践提高了学生的学习兴趣,培养了学生的创新思维和科研能力,为我校创新型、应用型人才的培养奠定基础。

关键词：科研成果教学复合材料

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低频标准真空涨落的测量

物理学报 2016年第4期65卷 148-154页

作者：薛佳秦际良张玉驰李刚张鹏飞张天才彭堃墀山西大学光电研究所量子光学与光量子器件国家重点实验室极端光学协同创新中心太原030006 山西大学物理电子工程学院太原030006

采用自平衡零拍方案,对低频段的标准量子真空涨落进行了测量.实验确定了该系统的饱和光功率约为3.2 mW.在10 Hz—400 kHz的频率范围内,系统的共模抑制比平均为55 dB,在100 Hz处高达63 dB,对激光经典技术噪声具有很强的抑制作用.当入射... 详细信息

采用自平衡零拍方案,对低频段的标准量子真空涨落进行了测量.实验确定了该系统的饱和光功率约为3.2 mW.在10 Hz—400 kHz的频率范围内,系统的共模抑制比平均为55 dB,在100 Hz处高达63 dB,对激光经典技术噪声具有很强的抑制作用.当入射光功率为400μW时,真空涨落噪声达到11 dB.此低频量子真空噪声探测系统可广泛应用于量子计量和量子光学等研究领域.

关键词：低频量子噪声平衡零拍探测共模抑制比