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Nano Research 2024年第7期17卷 6766-6772页

作者： Yi Xie Pengling Huang Qiang Gao Shiyu wang jianchen wang Gang Ye Collaborative Innovation Center of Advanced Nuclear Energy Technology Institute of Nuclear and New Energy TechnologyTsinghua UniversityBeijing 100084China

Safe confinement of fission iodine isotopes for long-term radioactive waste disposal remains a formidable challenge,as conventional sorbents provide inherently weak iodine-host *** report here a novel halogen bond(X-bond)directed strategy to sequester volatile iodine in hydrogen-bonded(H-bonded)frameworks with unprecedented ***-assisted Hbonded frameworks bearing open halide sites are developed,showing distinctive iodine encapsulation behaviors without compromising the *** crystallographic evidence indicates the formation of X-bonds,i.e.,I–I···Cl^(−) and I–I···Br^(−),within the confined pore *** polyhalogen anions,i.e.,[I_(2)Cl_(2)]^(2−)and[I_(2)Br_(2)]^(2−),sustained in H-bonded frameworks are identified for the first *** X-bond reinforced host-guest interaction affords robust iodine trapping without leaking out even at elevated temperatures up to 180℃.By integrating the halogen-bond chemistry with H-bonded frameworks,this study offers fresh concepts for developing effective host reservoirs to secure fission iodine isotopes from spent fuel reprocessing off-gases.

关键词： halogen-bond chemistry anion coordination chemistry hydrogen-bonded organic frameworks polyhalogen anions iodine confinement

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银行网络结构与系统性金融风险传染

系统工程理论与实践 2024年第7期44卷 2120-2136页

作者：杨科王健辰田凤平华南理工大学经济与金融学院广州510006 中山大学国际金融学院广州510275 人工智能与数字经济广东省实验室(广州) 广州510330

随着我国银行业资金规模和成员数量的不断增加,愈发复杂的机构间关联网络逐渐成为潜在的风险传染渠道.本文采用GARCH-Copula-CoVaR模型测算了16家上市商业银行在系统性金融风险中的贡献规模,结合网络拓扑理论和滑动窗口法研究了银行网... 详细信息

随着我国银行业资金规模和成员数量的不断增加,愈发复杂的机构间关联网络逐渐成为潜在的风险传染渠道.本文采用GARCH-Copula-CoVaR模型测算了16家上市商业银行在系统性金融风险中的贡献规模,结合网络拓扑理论和滑动窗口法研究了银行网络结构特征的演化趋势,并进一步分析了银行网络结构对系统性金融风险传染的影响机制.研究结果表明:虽然银行部门“去中心化”效应愈发显著,网络稳定性和抗风险能力整体上得到改善,但仍应重视网络结构特征在系统性金融风险产生及辐射过程中起到的多重作用;处于网络中不同风险传染地位的银行同时满足宏微观审慎监管要求的难度存在较大差异,对极端风险敏感且在银行网络中扮演核心角色的银行更倾向于向整个系统输出更多风险,通常在风险传染过程中起主导作用;在危机时期,网络密度通常会出现剧烈变化,关联网络的稳定性失衡进一步加速了系统性金融风险的传染.本研究可为监管部门实时更新系统重要性银行名单和全面监管风险传染渠道提供思路,对提升金融市场抵御风险的能力以及防范和化解系统性风险等方面都具有重要的现实意义.

关键词：银行网络结构系统性金融风险影响机制

Experimental study on NO_x emission correlation of fuel staged combustion in a LPP combustor at high pressure based on NO-chemiluminescence

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Chinese Journal of Aeronautics 2020年第2期33卷 550-560页

作者： Zhichao wang Yuzhen LIN jianchen wang Chi ZHANG Zhijun PENG National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Collaborative Innovation Center for Advanced Aero-EngineSchool of Energy and Power EngineeringBeihang UniversityBeijing 100083China Creative Arts Technologies and ScienceUniversity of BedfordshireLuton LU13JUUK

Experimental investigations on NOx emissions of a single-cup,Lean Premixed Prevaporized(LPP),module combustor were carried out at elevated inlet temperature and pressure up to810 K and 2.0 MPa,close to the real operating conditions of aero-engine *** LPP combustor adopts centrally staged fuel injections which could produce separated stratified swirling spray *** the NOx emissions measurements,the ranges of dome equivalence ratio and fuel stage ratio were from 0.55 to 0.58 and 8%to 24%,*** optical diagnosis on separated stratified swirling spray flame were carried out with fuel stage ratio changing from 15%to 30%.Therefore,NO*and OH*chemiluminescence images were *** results show that NOx emissions increase with the increase of the fuel stage *** from the chemiluminescence images,the main flame and pilot flame are found weakly *** pilot flame plays a significant role in NOx emission production because of its higher adiabatic flame *** on the results of chemiluminescence optical tests,a new NOx emission prediction model is proposed based on the Lefebvre’s single flame model The estimate of local equivalence ratio of the pilot stage’s nonpremixed flame is modified considering the characteristics of spray combustion,and a"PLUS"emission prediction model suitable for separated stratified swirling spray flame is *** to the experimental data,the"PLUS"model exhibits a good prediction in a range of±13%of deviation.

关键词： Combustors Lean staged combustion Low emissions NOx correlation Optical diagnosis

Direction navigability analysis of geomagnetic field based on Gabor filter

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Journal of Systems Engineering and Electronics 2018年第2期29卷 378-385页

作者： XIAO Jing DUAN Xiusheng QI Xiaohui wang jianchen Army Engineering University Shijiazhuang 050003China Government Representative Office Northwestern Polytechnical UniversityXi’an 710065China

Direction navigability analysis is a supplement to the navigability analysis theory, in which extraction of the direction suitable-matching features(DSMFs) determines the evaluation performance. A method based on the Gabor filter is proposed to estimate the direction navigability of the geomagnetic field. First,the DSMFs are extracted based on the Gabor filter’s ***, in the view of pattern recognition, the classification accuracy in fault diagnosis is introduced as the objective function of the hybrid particle swarm optimization(HPSO) algorithm to optimize the Gabor filter’s parameters. With its guidance, the DSMFs are extracted. Finally, a direction navigability analysis model is established with the support vector machine(SVM), and the performances of the models under different objective functions are discussed. Simulation results show the parameters of the Gabor filter have a significant influence on the DSMFs, which, in turn, affects the analysis results of direction navigability. Moreover, the risk of misclassification can be effectively reduced by using the analysis model with optimal Gabor filter parameters. The proposed method is not restricted in geomagnetic navigation, and it also can be used in other fields such as terrain matching and gravity navigation.

关键词： geomagnetic navigation navigability analysis direction navigability Gabor filter direction suitable-matching feature

人类命运共同体对马克思世界历史理论的继承与发展

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泉州师范学院学报 2024年第3期42卷 10-15,43页

作者：王建晨杨舒涵新疆大学马克思主义学院新疆乌鲁木齐830046 新疆大学政治与公共管理学院新疆乌鲁木齐830046

马克思世界历史理论以唯物史观为基础,通过阐释人类社会发展的进程,揭示出社会历史发展的必然规律。习近平总书记审时度势,深刻分析当今世界发展趋势和人类社会发展的前进方向,提出人类命运共同体的科学理念,为解决人类问题提供了中国... 详细信息

马克思世界历史理论以唯物史观为基础,通过阐释人类社会发展的进程,揭示出社会历史发展的必然规律。习近平总书记审时度势,深刻分析当今世界发展趋势和人类社会发展的前进方向,提出人类命运共同体的科学理念,为解决人类问题提供了中国智慧和中国方案。人类命运共同体在历史趋向、理论基础和价值旨归方面与马克思世界历史理论一脉相承,既展示了马克思世界历史理论强大的生命力,同时也彰显人类命运共同体与时俱进的时代价值。

关键词：马克思世界历史理论人类命运共同体

吩嗪类衍生物用于快速充放电和长寿命的水系钾离子全电池负极

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Science China Materials 2024年第5期67卷 1464-1470页

作者：郑易帆于丹丹王健晨杨杰罗稳戈天奇秦来顺黄岳翔陈达 College of Materials and Chemistry China Jiliang UniversityHangzhou310018China Hydrogen Energy Research Center PetroChina Petrochemical Research Institute Beijing102200China

有机电极材料因具有结构多样性和可持续性,在水系钾离子电池研究领域展示出广阔的前景,但它们大多数存在导电性差、易溶于电解液的问题,导致电极活性物质利用率低、循环稳定性差.本文通过含氮苯环的共轭延申、引入氰基活性中心,获得了3C... 详细信息

有机电极材料因具有结构多样性和可持续性,在水系钾离子电池研究领域展示出广阔的前景,但它们大多数存在导电性差、易溶于电解液的问题,导致电极活性物质利用率低、循环稳定性差.本文通过含氮苯环的共轭延申、引入氰基活性中心,获得了3CN-HATN.与经#吩嗪负极相比,3CN-HATN的最低未占据分子轨道能级更低,更容易被还原,且其能带隙较窄,改善了导电性,其共轭结构可有效抑制循环过程中3CN-HATN的溶解.3CN-HATN负极在80 C(1 C=350 mA g^(-1))下比容量高达233.8 mA h g^(-1),将其与Ni(OH)_(2)正极匹配,构建的水系钾离子全电池具备优异的循环稳定性和快充性能,30 C下循环10,000圈后容量保持率达81.5%.

关键词： aqueous rechargeable batteries π-conjugated structure organic electrodes K+storage phenazine derivatives

Experimental Investigations of the Flow Field Structure and Interactions between Sectors of a Double-Swirl Low-Emission Combustor

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Journal of Thermal Science 2020年第3期29卷 43-51页

作者： FAN Xiongjie XU Gang LIU Cunxi wang jianchen LIN Yuzhen ZHANG Chi Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Collaborative Innovation Center of Advanced Aero-EngineSchool of Energy and Power EngineeringBeihang UniversityBeijing 100191China

In this paper,the flow field characteristics of a double-swirl low-emission combustor were analyzed by using Particle Imaging Velocimetry(PIV)technology in an optical three-sector combustor test *** interactions between sectors and the flow field structure were *** results illustrated that there was a big difference between the flow field structures of the middle sector and the side sector under the same pressure drop,which was mainly induced by the interactions between *** interactions made the swirl intensity of the middle sector weaker than that of the side sector,which made the recirculation zone of the middle sector be smaller than that of the side *** the increase of swirler pressure drop,the jet velocity at the exit of the swirler,the jet expansion angle,the width of the recirculation zone and the recirculating speed of the central axis became larger,enhancing the interactions between air streams from middle sector and side *** flow velocity in the central plane between sectors was small,especially the radial velocity,mainly because of the loss of the swirl intensity by the interactions between flow field of adjacent *** expansion angle determined the position of the vortex in the primary recirculation zone;the axial and radial position of the vortex move downstream and radial outward with the increase of the jet expansion *** results of the mechanism of flow field organization in this study can be used to support the design of new low-emission combustor.

关键词： combustor recirculation zone Particle Imaging Velocimetry(PIV) pressure drop

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基于热图像的GWOA-BiLSTM机床主轴热误差预测

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制造技术与机床 2024年第8期 175-181页

作者：张婉君陈瑶韩越吴弘毅王建臣邓小雷衢州学院浙江省空气动力装备技术重点实验室浙江衢州324000 浙江工业大学机械工程学院浙江杭州310023

热误差是影响高精密数控机床加工精度的重要因素。为了提高机床加工精度和性能,减少机床运行中产生的热误差,文章提出一种基于热图像的灰狼优化算法(grey wolf optimization algorithm,GWOA)和双向长短期记忆神经网络(bidirectional lon... 详细信息

热误差是影响高精密数控机床加工精度的重要因素。为了提高机床加工精度和性能,减少机床运行中产生的热误差,文章提出一种基于热图像的灰狼优化算法(grey wolf optimization algorithm,GWOA)和双向长短期记忆神经网络(bidirectional long short-term memory,BiLSTM)混合的热误差预测模型。首先,采用热成像仪获取机床主轴区域的温度场信息;其次,利用DBSCAN聚类(density-based spatial clustering of applications with noise)算法和相关系数法筛选出温度敏感点;然后,通过模拟灰狼群体捕食行为,在参数空间中进行搜索以找到BiLSTM所需的最优参数;最后,使用获得的机床温度敏感点和热位移数据进行热误差预测,并在试验机床上进行验证。实验结果表明,使用GWOA优化BiLSTM神经网络的预测模型相比BiLSTM神经网络预测模型的均方根误差(root mean square error,RMSE)和平均绝对误差(mean absolute error,MAE)分别减小了约0.5180、0.3823μm,决定系数R^(2)提升了0.0578。与BiLSTM神经网络模型相比,利用GWOA优化后的模型具有更加优良的预测性能。

关键词：热图像灰狼优化算法 BiLSTM神经网络热误差建模机床测点优化

Experimental investigations of the spray structure and interactions between sectors of a double-swirl low-emission combustor

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Chinese Journal of Aeronautics 2020年第2期33卷 589-597页

作者： Xiongjie FAN Cunxi LIU Gang XU Chi ZHANG jianchen wang Yuzhen LIN School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeihang UniversityBeijing 100083China

In this paper,the spray characteristics of a double-swirl low-emission combustor are analyzed by using Particle Imaging Velocimetry(PIV)and Planar Laser Induced Fluorescence(PLIF)technologies in an optical three-sector combustor test *** between sectors and the influence of main stage swirl intensity on spray structure are *** results illustrate that the swirl intensity has great effect on the flow field and spray *** spray cone angle is bigger when the swirl number is 0.7,0.9 than that when the swirl number is *** fuel distribution zone is larger and the distribution is more uniform when the swirl number is *** fuel concentration in the center area of the center plane of side sector(Plane 5)is larger than that of the center plane of middle sector(Plane 1).The spray cone angle in Plane 5 is larger than that in Plane *** width of spray cone becomes larger with the increase of Fuel-Air Ratio(FAR),whereas the spray cone angle under different fuel-air ratios are absolutely the *** results of the mechanism of spray organization in this study can be used to support the design of new low-emission combustor.

关键词： Combustor Fuel-air ratio PIV PLIF Pressure drop Swirl intensity

基于非参数回归响应面法的高精车铣复合机床床身多目标联合优化设计

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制造技术与机床 2024年第5期 128-133页

作者：杨郡守周振伟林晓亮邓小雷王建臣郑燕宁衢州学院浙江省空气动力装备技术重点实验室浙江衢州324000 台钰精机(浙江)有限公司浙江衢州324000

精密化是机械加工领域追求的目标,数控车铣复合机床作为高端机械加工装备,其床身的动静态特性对机床加工精度有显著影响。针对当前床身结构优化方法效率低、效果差的问题,文章提出一种非参数响应面法的多目标联合优化方案。该方案首先... 详细信息

精密化是机械加工领域追求的目标,数控车铣复合机床作为高端机械加工装备,其床身的动静态特性对机床加工精度有显著影响。针对当前床身结构优化方法效率低、效果差的问题,文章提出一种非参数响应面法的多目标联合优化方案。该方案首先根据有限元分析结果挑选出模型的优化尺寸,并将床身质量、最大形变、一阶固有频率作为联合优化目标;通过建立参数试验对尺寸进行敏感性分析,精准选出敏感性较大尺寸;基于非参数回归法建立响应面,导入所选尺寸,计算试验样本的响应值,建立非参数回归响应面优化模型,并采用多目标遗传算法找出最优设计方案。最优方案优化结果为:机床床身最大形变降低约14.667%,一阶固有频率提升约3.187%,质量降低约1.208%。结果表明该优化方案能够高效提升机床床身动静态特性,为机床优化设计提供理论依据。

关键词：高精车铣复合机床机床床身参数敏感性分析非参数回归响应面法多目标联合优化