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基于流场调控的PEM电解槽多目标性能优化
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作者 王亮 刘银萍 +8 位作者 饶云松 郭琳 宋暄 苑盛伟 李东芳 肖俊亮 齐豪 徐春明 徐泉 《石油学报(石油加工)》 北大核心 2026年第2期607-615,共9页
质子交换膜(PEM)电解槽作为清洁能源转换的关键技术,其效率和稳定性受到气-液传输和热管理等因素的限制。为了解决这些问题,建立多物理场稳态仿真系统,选取PEM电解槽阳极入口水流速0.05~0.50 m/s范围内的10个典型水流速点,对不同入口水... 质子交换膜(PEM)电解槽作为清洁能源转换的关键技术,其效率和稳定性受到气-液传输和热管理等因素的限制。为了解决这些问题,建立多物理场稳态仿真系统,选取PEM电解槽阳极入口水流速0.05~0.50 m/s范围内的10个典型水流速点,对不同入口水流速下PEM电解槽阳极催化层的速度场、温度场、氧气体积分数、液态水饱和度、电流密度、过电位和压降等关键参数进行定量分析对比。结果表明:适当提升进水流速能够显著改善氧气输运能力、降低过电位和提升电流密度,但过高水流速(0.40~0.50 m/s)可能引发局部氧气富集和气体阻塞,影响水管理效率和反应均匀性,同时导致整体温度偏低;而低水流速(0.05~0.15 m/s)下温度分布均匀且利于反应维持。因此,在传质效率、热管理与电化学性能之间实现最佳权衡下推荐阳极入口水流速为0.25 m/s,研究结果为PEM电解槽的流场结构优化和运行参数调控提供了理论依据。 展开更多
关键词 质子交换膜(pem) 电解槽 蛇形流道 多物理场仿真 数值模拟
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PEM电解技术对矿山酸性废水中(类)金属的处理效果
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作者 李丹霓 毛启明 +4 位作者 魏建宏 郭靖 卜心愿 张彦勰 罗琳 《金属矿山》 北大核心 2026年第3期226-238,共13页
采矿活动产生的矿山酸性废水(AMD)呈强酸性,含有高浓度的Fe^(2+),并伴有(类)金属污染。为实现AMD的高效处理,本研究建立了质子交换膜(PEM)电解系统。系统在最优条件下(铱钛网阳极,铂片阴极,15 g/L S将p H为2.5~4.5,Fe^(2+))浓度为200~80... 采矿活动产生的矿山酸性废水(AMD)呈强酸性,含有高浓度的Fe^(2+),并伴有(类)金属污染。为实现AMD的高效处理,本研究建立了质子交换膜(PEM)电解系统。系统在最优条件下(铱钛网阳极,铂片阴极,15 g/L S将p H为2.5~4.5,Fe^(2+))浓度为200~800 mg/L,含50 mg/L Fe^(3+)(Mn^(2+)、Cr^(3+)、Cu^(2+)、Zn^(2+)或As^(5+))的AMD中(类)金属浓度在290 min内降至符合饮用水标准。其除Fe效率与初始p H(2.5~4.5)正相关,与初始Fe^(2+)浓度(200~800 mg/L)负相关。50 mg/L Fe^(3+)、Cu^(2+)和Zn^(2+)对其除Fe^(2+)起抑制作用,Mn^(2+)和Cr^(3+)起促进作用,As^(5+)无影响。产物表征证明,AMD中Fe^(2+)初期部分被溶解氧氧化为(氢)氧化铁,部分水解为(氢)氧化亚铁,末期溶解再结晶为Fe_(3)O_(4);Fe^(3+)、Mn^(2+)、Cr^(3+)、Cu^(2+)和Zn^(2+)与Fe^(2+)共沉淀为金属氧化物;As^(5+)被铁矿物吸附。 展开更多
关键词 矿山酸性废水 pem电解技术 (类)金属 去除途径
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35 MPa高压直产氢PEM水电解压力对开路电压的影响机理与建模研究
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作者 干思杰 李桦 +4 位作者 李炳钟 周俊龙 黄克起 王誉霖 方金石 《电气工程学报》 北大核心 2026年第1期129-138,共10页
针对超高压运行下电压变化机理尚不清晰的问题,探讨了压力对PEM电解槽开路电压的影响。首先,基于能斯特方程推导了开路电压(Open-circuit voltage,OCV)与压力的关系;然后,在不同温度(40℃、60℃、80℃)和阴阳两极反应压力(0.1 MPa、3.5 ... 针对超高压运行下电压变化机理尚不清晰的问题,探讨了压力对PEM电解槽开路电压的影响。首先,基于能斯特方程推导了开路电压(Open-circuit voltage,OCV)与压力的关系;然后,在不同温度(40℃、60℃、80℃)和阴阳两极反应压力(0.1 MPa、3.5 MPa、35 MPa)下开展极化曲线测试,分析电解压力对电压变化的规律;最后,对比实验得到的平均电压增量与理论电压增量,提出了与温度有关的经验修正系数γ,并建立二次多项式经验模型。结果表明,压力升高使极化曲线整体上移,且电压增量与压力比呈对数关系;此外,温度升高会使电压水平整体降低。修正模型有效弥合了实验与理论的偏差,拟合优度R^(2)=0.93195。在35 MPa下进行的200 h恒电流运行实验表明高压下电解槽运行稳定,平均产氢电耗为4.04(kW·h)/Nm^(3);同时,高压运行还能显著降低接触电阻老化率。研究结果揭示了超高压运行对开路电压的作用机制,为高压直产氢系统的工况设计与能效提升提供了参考依据。 展开更多
关键词 超高压 pem电解槽 能斯特方程 开路电压 经验修正系数 老化率
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PEM燃料电池催化剂碳壳包覆技术
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作者 朱蔡瀚 李德威 王宇楠 《汽车安全与节能学报》 北大核心 2026年第1期79-87,共9页
针对质子交换膜(PEM)燃料电池中铂基催化剂存在的铂颗粒团聚与溶解问题,为提升催化剂的活性与耐久性,该文提出一种多巴胺预聚包覆策略。通过物理隔离方式实现对介孔碳催化剂外表面铂颗粒的选择性碳壳包覆;系统研究了浸渍时间、预聚时间... 针对质子交换膜(PEM)燃料电池中铂基催化剂存在的铂颗粒团聚与溶解问题,为提升催化剂的活性与耐久性,该文提出一种多巴胺预聚包覆策略。通过物理隔离方式实现对介孔碳催化剂外表面铂颗粒的选择性碳壳包覆;系统研究了浸渍时间、预聚时间及多巴胺浓度对催化剂孔结构、碳壳形貌及电化学性能的影响。结果表明:铂颗粒的选择性碳壳包覆敏感因素从大到小为预聚时间、浸渍时间、多巴胺浓度;优化得到的最佳碳壳包覆参数为预聚90 min、浸渍10 min、多巴胺浓度0.3 mg/mL,得到的碳壳包覆催化剂介孔结构保持率达95%,碳壳厚度约为0.83 nm。半波电位较原始催化剂提升46 mV;经过3万圈加速老化测试后半波电位仅衰减5 mV,较原始催化剂提升了86%。 展开更多
关键词 质子交换膜(pem)燃料电池 催化剂改性 碳壳包覆技术
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Dynamics of Nonlinear Rossby Waves With the Derivative-Expansion Method
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作者 TIAN Hongxiao ZHANG Ruigang LIU Quansheng 《应用数学和力学》 北大核心 2026年第3期313-328,共16页
Nonlinear Rossby waves are used to describe typical wave phenomena in large-scale atmosphere andocean.Owing to the nonlinearity of the involved problems,the weakly nonlinear method,ie the derivative ex-pansion method,... Nonlinear Rossby waves are used to describe typical wave phenomena in large-scale atmosphere andocean.Owing to the nonlinearity of the involved problems,the weakly nonlinear method,ie the derivative ex-pansion method,was mainly used to investigate Rossby waves under the combined effects of the generalizedβ-effect and the basic flow effect.The derivative expansion method has the advantage of capturing the multi-scalecharacteristics of wave processes simultaneously.In the case where the perturbation expansion is independentof secular terms,the nonlinear equations describing the amplitude evolution of nonlinear waves were derived,such as the Korteweg-de Vries equation,the Boussinesq equation and Zakharov-Kuznetsov equation.Both quali-tative and quantitative analyses indicate that the generalizedβ-effect is the key factor inducing the evolution ofRossby solitary waves. 展开更多
关键词 planetary Rossby waves generalized beta effect derivative-expansion method nonlinear equation
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Influence of SiC Content on Foaming Stability,Cell Structure,and Compression Performance of SiC/Al-Based Composite Foam Prepared by Two-Step Foaming Method
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作者 Huang Wenzhan Liu Tao +3 位作者 Chen Yao Wang Lucai Wu Jianguo You Xiaohong 《稀有金属材料与工程》 北大核心 2026年第4期890-898,共9页
SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminu... SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminum foams was investigated.The macro/micro-features of the aluminum foams were characterized and analyzed.Results demonstrate that an appropriate increase in SiC content and the uniform distribution of SiC can improve the foaming stability,optimize the cell diameter and cell wall thickness,ameliorate the cell distribution,and enhance the hardness and compressive strength of the aluminum foams.However,either insufficient or excessive SiC leads to uneven distribution of SiC particles,which is unfavorable to foaming stability and good cell structure formation.With 6wt%SiC,both the foaming stability and cell structure of the aluminum foam reach the optimal state,resulting in the highest compressive strength and optimal energy absorption capacity. 展开更多
关键词 aluminum foam two-step foaming method foaming stability cell structure HARDNESS compressive strength
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Broadband ground motion simulation and analysis of a near-fault 3D basin-mountain coupling site based on the hybrid method
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作者 Liu Zhongxian Tang Kang +2 位作者 Li Chengcheng Yuan Xiaoming Zhang Hai 《Earthquake Engineering and Engineering Vibration》 2026年第1期87-110,共24页
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE... This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions. 展开更多
关键词 hybrid ground motion simulation method spectral element method three-dimensional stochastic finite fault method near-fault basin-mountain coupling effect basin effect nonlinear effect
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Study on the effect of preparation method on denitration performance of Co-modified Ce/TiO_(2) catalyst
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作者 YU Chao ZHANG Boya +2 位作者 SHEN Kai HAN Yuxuan ZHANG Yaping 《燃料化学学报(中英文)》 北大核心 2026年第3期79-91,共13页
This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s... This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s low-temperature denitrification activity.After identifying optimal preparation parameters via condition screening,multiple characterization techniques-including BET,XRD,XPS,H_(2)-TPR and in situ DRIFTS-were employed to deeply analyze the catalyst’s physicochemical properties and reaction mechanism.Results demonstrated that compared to the impregnation and co-precipitation methods,the Ce-Co_(0.025)/TiO_(2)-SG catalyst(prepared by the sol-gel method with a Co/Ti mass ratio of 0.025)exhibited significantly superior denitrification activity:NO conversion remained stably above 95%in the 225−350℃ temperature range,and it displayed high N_(2) selectivity.Characterization analysis revealed that abundant surface oxygen vacancies,a high proportion of Ce^(3+) species,and prominent acidic sites collectively contributed to enhancing its low-temperature denitrification performance.This work provides reference value for the development of highly efficient low-temperature denitrification catalysts. 展开更多
关键词 preparation method Co Ce/TiO_(2) low-temperature denitration NH_(3)-SCR
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光伏PEM电解水制氢系统仿真与控制
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作者 朱子恺 黄晶晶 罗必雄 《电力勘测设计》 2026年第1期1-11,56,共12页
氢能具有来源多样、清洁低碳等优点,是未来极具前景的能源形式。在诸多电解制氢路线中,质子交换膜(PEM)电解水由于其宽负荷范围和高响应速度,更适合匹配可再生能源。随着光伏发电成本的不断下降,开发光伏制氢技术,将可再生能源剩余的电... 氢能具有来源多样、清洁低碳等优点,是未来极具前景的能源形式。在诸多电解制氢路线中,质子交换膜(PEM)电解水由于其宽负荷范围和高响应速度,更适合匹配可再生能源。随着光伏发电成本的不断下降,开发光伏制氢技术,将可再生能源剩余的电能转换成氢能,实现整个制氢过程的零碳排放,在“双碳”政策背景下,具有重大战略意义。针对当前光伏制氢仿真仅关注电学特性、动态性差等问题,本文采用Matlab/Simulink平台建立PEM电解水制氢系统电化学热力学动态耦合模型,根据光伏组件和PEM电解水制氢系统参数,匹配设计光伏阵列系统和BUCK变换器参数,使得PEM电解水制氢系统在峰值辐照度下以额定制氢量制氢,实现整个光伏电解水制氢系统的仿真与控制。仿真结果验证了匹配设计的正确性和控制策略的有效性,对光伏PEM电解水制氢技术的研究提供了参考。 展开更多
关键词 光伏制氢 质子交换膜电解槽 最大功率点跟踪控制 BUCK变换器
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Establishment of a Determination Method for Fruit Texture in Chieh-qua Using Texture Analyzer
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作者 Ying WANG Xuan DU Na LIU 《Agricultural Biotechnology》 2026年第1期54-59,共6页
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun... [Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua. 展开更多
关键词 CHIEH-QUA Texture analyzer Texture quality Determination method
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A novel scaling method for the elastic ring supporting structure of an aero-engine rotor system: analytical and experimental investigations
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作者 Lei LI Tianyue MA +4 位作者 Zhong LUO Dongwu GAO Xiangdong GE Hui MA Shibin WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期1-18,共18页
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr... The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings. 展开更多
关键词 rotor system AERO-ENGINE elastic ring scaling method supporting structure
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Multiphysics Implicit Coupling Method for Fluid,Particles,and Large-Deformation Structures
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作者 Xiangxiang Wang Hualong Xie +3 位作者 Yue Yu Min Li Yubin Wang Fei Xing 《Computer Modeling in Engineering & Sciences》 2026年第2期367-401,共35页
This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,Calcu... This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,CalculiX,and preCICE to simulate fluid-particle-structure interactions with large deformations.Mesh motion in the fluid field is handled using the radial basis function(RBF)method.The particle phase is modeled by MPPIC,where fluid-particle interaction is described through momentum exchange,and inter-particle collisions are characterized by collision stress.The structural field is solved by nonlinear FEM to capture large deformations induced by geometric nonlinearity.Coupling among fields is realized through a partitioned,parallel,and non-intrusive iterative strategy,ensuring stable transfer and convergence of interface forces and displacements.Notably,the influence of particles on the structure is not direct but mediated by the fluid,while structural motion directly affects particle dynamics.The results demonstrate that the proposed approach effectively captures multiphysics interaction processes and provides a valuable reference for numerical modeling of coupled fluid-particle-structure systems. 展开更多
关键词 Fluid-particle-structure interaction large deformation partitioned method non-intrusive coupling
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A Cost-Effective Approach to Precisely Estimate Singlet-Triplet Energy Gaps in MR-TADF Molecules:Combining Delta Self-Consistent Field and Time-Dependent Density Functional Theory Methods
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作者 Qian Jina Dong Wang 《Chinese Journal of Chemical Physics》 2026年第1期41-50,I0021-I0032,I0042,共23页
As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency... As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters. 展开更多
关键词 Organic light-emitting diode Multiple resonance thermally activated delayed fluorescence emitter Single-triplet energy gap Delta self-consistent field method Time-de-pendent density functional theory method
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Synchronization Stability Analysis of Multi-VSC Grid-connected System via Multi-scale Method
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作者 Meng Huang Yangjian Ling +3 位作者 Han Yan Xikun Fu Xiaoming Zha Herbert Ho-Ching Iu 《CSEE Journal of Power and Energy Systems》 2026年第1期282-293,共12页
In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this pap... In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this paper,these influences are investigated from the perspective of the time domain.First,a novel time-domain model of the multi-VSC system is obtained by using a multi-scale method.On this basis,a stability criterion is proposed to assess the synchronization stability of the system.Then,the accuracy of the time-domain model and its stability criterion in various conditions are discussed.Moreover,the negative impact of the interaction on the system is quantified.Finally,the above theoretical analysis is also verified in the controller hardware-in-the-loop(CHIL)experiments. 展开更多
关键词 Multi-scale method multi-VSC phase-locked loops synchronization stability time-domain model
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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On the Use of the Nelder-Mead Simplex Method in Control Design and Systems Theory
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作者 Laura Menini Corrado Possieri Antonio Tornambe 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期186-204,共19页
The Nelder-Mead simplex method is a well-known algorithm enabling the minimization of functions that are not available in closed-form and that need not be differentiable or convex.Furthermore,it is particularly parsim... The Nelder-Mead simplex method is a well-known algorithm enabling the minimization of functions that are not available in closed-form and that need not be differentiable or convex.Furthermore,it is particularly parsimonious on the number of function evaluations,thus making it preferable to convex optimization paradigms in the case,common when dealing with control design problems,that the objective function of the optimization problem is non-differentiable,non-convex,and its closed-form is not available or difficult to be computed analytically.The main goal of this paper is to show how the joint use of the Nelder-Mead simplex method and the Morrison algorithm can be successfully used to solve relevant and challenging control problems that cannot be easily solved using analytic methods.In particular,it is shown how the problems of strong stabilization,static output feedback stabilization,and design of robust controllers having fixed structure can be framed as optimization problems,which,in turn,can be efficiently solved by coupling the two above mentioned algorithms.The performance of this procedure is compared with state-of-the-art techniques on dozens of static output feedback benchmark case studies,and its effectiveness is demonstrated by several examples. 展开更多
关键词 Optimization method robust controller static output feedback strong stabilizability
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Investigation of equivalent strength parameters of soil-rock mixture using numerical manifold method
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作者 Junfeng Li Yongtao Yang +2 位作者 Yang Xia Hong Zheng Shuilin Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期637-650,共14页
As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalen... As binary geological media,soil-rock mixtures(SRMs)exhibit a distinct gradational composition,leading to their unique mechanical behaviors.To appraise the stability of SRM slopes,it is essential to determine equivalent parameters of SRMs,which are typically obtained through experimental and numerical methods.In contrasted to other numerical methods,the numerical manifold method(NMM)is more effective in addressing SRM problems.This is because the high-precision regular mathematical meshes in NMM can be used without aligning with the soil-rock interfaces and boundaries of SRMs.In the current research,the equivalent strength parameters of SRMs,i.e.the equivalent cohesion ce and internal friction angleϕ_(e),are determined using NMM.Initially,an NMM triaxial numerical model is established and validated based on triaxial experiments.Subsequently,the soil and rock parameters are derived through parameter inversion.Moreover,the impacts of rock content,size,shape and rock blocks'major-axis orientation on ce andϕ_(e) of SRMs are thoroughly examined using the NMM triaxial numerical model.Additionally,a fitting function is proposed to linkϕ_(e) to the rock content and size of SRMs.When other influencing factors are fixed,the above fitting model leads to the following conclusions:(1)the predictedϕ_(e) of SRMs increase with the increase of rock content;and(2)SRM samples with smaller rocks display a higher predictedϕ_(e). 展开更多
关键词 Soil-rock mixtures Equivalent strength parameters Numerical manifold method
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Subtitle Translation Methods of The Good Wife From Functional Equivalence Perspective
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作者 WANG Ya-kun BAO De-wang 《Journal of Literature and Art Studies》 2026年第1期26-30,共5页
The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to... The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to analyze the methods of its English-to-Chinese subtitle translation by considering social,cultural,and historic backgrounds between China and America.After data collection and case analysis,the study found that:(1)Five major translation methods are adopted in the subtitle translation of The Good Wife.They are free translation,variation,literal translation,addition,and omission.Among them,free translation is the most frequently used,while omission is used least.(2)The subtitle translation of films and TV series is limited by time and space restrictions,social-cultural differences,and other factors.When translating,translators should try to use humorous words,euphemism,intonation,and other ways,and combine different methods such as literal translation,free translation,variation,addition,omission,and other methods to seek equivalence both in the meaning and function of subtitles under the guidance of Functional Equivalence Theory. 展开更多
关键词 subtitle translation Functional Equivalence Theory The Good Wife translation methods
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Pile installation effects in natural soft clays:A semi-analytical solution using strain path method
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作者 Liang Li Pan Zhou +3 位作者 Jingpei Li Seyedmohsen Miraei Peng Feng Mingdong Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期728-744,共17页
This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture ... This paper develops a semi-analytical solution for pile penetration in natural soft clays using the strain path method(SPM).The stress-strain behavior of soils is characterized by the S-CLAY1S model,which can capture the anisotropic evolution and destructuring nature of soft clays.By integrating the S-CLAY1S model into the theoretical framework of the SPM,a set of ordinary differential equations is formulated with respect to the vertical coordinate of soil particles.The distribution of excess pore water pressure(EPWP)following pile installation is approximated through one-dimensional(1D)radial integration around the pile shaft.The distribution of stresses and EPWP,along with the evolution of fabric anisotropy within the soil surrounding the pile,is presented to illustrate the response of pile penetration in natural soft clays.The proposed solution is validated against existing theoretical solutions using the SPM and cavity expansion method(CEM),along with experimental data.The findings demonstrate that the SPM reveals lower radial effective stresses and EPWP at the pile shaft than that of CEM.Pile penetration alters the soil's anisotropic properties,inducing rotational hardening and affecting post-installation stress distribution.Soil destructuration eliminates bonding among particles near the pile,resulting in a complete disruption of soil structure at the pile surface,which is particularly pronounced for higher initial soil structure ratios.Minimal variation was observed in the three principal stresses and shear stress on the cone side surface as the angle increased from 18°to 60°,except for a slight reduction in EPWP. 展开更多
关键词 Pile penetration Strain path method Natural soft clays Anisotropy evolution Destructuration
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