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基于midas Gen的单层球形网壳结构分析及应用研究
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作者 王亮 聂向东 +2 位作者 崔传峰 秦兴宽 梁思浩 《建筑技术》 2024年第5期583-587,共5页
基于midas Gen软件模型,在不同应力比下对实体工程金属网壳模型进行分析,获得了工程实体金属网壳模型静力荷载下铸钢铰支座反力、罕遇地震时铸钢铰支座反力、静力荷载销轴反力、罕遇地震销轴反力分布情况。将设计模型得到的实体工程金... 基于midas Gen软件模型,在不同应力比下对实体工程金属网壳模型进行分析,获得了工程实体金属网壳模型静力荷载下铸钢铰支座反力、罕遇地震时铸钢铰支座反力、静力荷载销轴反力、罕遇地震销轴反力分布情况。将设计模型得到的实体工程金属网壳荷载–位移曲线与有关设计模型网壳荷载–位移曲线进行对比,通过实体工程金属网壳模型设计实例,分析了不同应力下的杆件位移情况,从而证明了实体工程金属网壳模型设计的准确性及合理性。 展开更多
关键词 midas gen 实体工程金属网壳 荷载–位移 设计实例 模型设计
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Detection of Turbulence Anomalies Using a Symbolic Classifier Algorithm in Airborne Quick Access Record(QAR)Data Analysis
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作者 Zibo ZHUANG Kunyun LIN +1 位作者 Hongying ZHANG Pak-Wai CHAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1438-1449,共12页
As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The ... As the risks associated with air turbulence are intensified by climate change and the growth of the aviation industry,it has become imperative to monitor and mitigate these threats to ensure civil aviation safety.The eddy dissipation rate(EDR)has been established as the standard metric for quantifying turbulence in civil aviation.This study aims to explore a universally applicable symbolic classification approach based on genetic programming to detect turbulence anomalies using quick access recorder(QAR)data.The detection of atmospheric turbulence is approached as an anomaly detection problem.Comparative evaluations demonstrate that this approach performs on par with direct EDR calculation methods in identifying turbulence events.Moreover,comparisons with alternative machine learning techniques indicate that the proposed technique is the optimal methodology currently available.In summary,the use of symbolic classification via genetic programming enables accurate turbulence detection from QAR data,comparable to that with established EDR approaches and surpassing that achieved with machine learning algorithms.This finding highlights the potential of integrating symbolic classifiers into turbulence monitoring systems to enhance civil aviation safety amidst rising environmental and operational hazards. 展开更多
关键词 turbulence detection symbolic classifier quick access recorder data
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A Study on the Symbol-Based Narrative in the International Communication of Cities
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作者 Zhang Li 《Contemporary Social Sciences》 2024年第4期41-52,共12页
Cultural symbols,a manifestation of cities’cultural resources,are not only signs that frame concepts but also forms that express meanings.Exploring the international communication of cities from the perspective of sy... Cultural symbols,a manifestation of cities’cultural resources,are not only signs that frame concepts but also forms that express meanings.Exploring the international communication of cities from the perspective of symbols,this paper analyzes in depth how cities create their cultural symbols in the dynamic process of international communication in an era of symbol-based digital media,and how they develop their narratives and explain meanings through the dissemination of symbols when telling their stories to international audiences,thus enhancing the efficiency and effectiveness of their international communication efforts. 展开更多
关键词 CITIES international communication cultural symbols city narratives
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药物检测机构营销策略研究——以GEN公司为例
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作者 谢恩耀 《中国市场》 2024年第8期100-104,共5页
当下处于经济迅速复苏的后疫情时代,政府及人民对于药物安全性提出了更高要求,而当前市场中存在大量的药物公司,其运营过程中需要药物检测企业的深度参与。随着药品研发环境的不断发展变化,药物检测机构作为新兴的社会力量在社会活动中... 当下处于经济迅速复苏的后疫情时代,政府及人民对于药物安全性提出了更高要求,而当前市场中存在大量的药物公司,其运营过程中需要药物检测企业的深度参与。随着药品研发环境的不断发展变化,药物检测机构作为新兴的社会力量在社会活动中的角色越来越重要。文章基于案例实证分析的研究思路,以GEN公司为研究对象,客观分析其所面对的宏观及微观环境,明晰当下的可利用优势及市场机遇,制定合理可行的实施计划及相适应的职能策略。文章的主要研究目标是通过对GEN公司自身运营资源、技术能力、市场环境等情况的剖析,充分发挥自身优势,有效规避市场风险,建立健全企业管理体系,优化内部运行机制,为企业的运营管理充分赋能,提升药物检测企业的核心竞争能力,助力企业实现高质量经营发展。目前,我国药物检测认证企业尚处于高速发展阶段,GEN公司当前所面临的问题具有一定的代表性,文章研究讨论的意见及观点既能对GEN公司的经营管理产生有效促进作用,亦对药物市场上的多数同质公司有一定的参考借鉴意义。 展开更多
关键词 药物检测企业 gen公司 动态平衡 营销策略
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Symbols in The Magic Barrel
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作者 FU He-yuan 《Journal of Literature and Art Studies》 2024年第1期48-53,共6页
The article takes the famous modern American Jewish writer Bernard Malamud’s novel The Magic Barrel as the object of study,and uses symbolism to interpret it,analyzing it one by one in terms of the magic barrel,the c... The article takes the famous modern American Jewish writer Bernard Malamud’s novel The Magic Barrel as the object of study,and uses symbolism to interpret it,analyzing it one by one in terms of the magic barrel,the colors,the seasons and the windows,respectively,so as to reveal the process of getting rid of the childishness within the novel’s male protagonist,Leo Finkel,who is maturing,as well as the novel’s Jewish theme of searching for the soul of the self. 展开更多
关键词 symbol magic barrel WINDOW
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Midas Gen在输水工程水池结构计算中的应用
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作者 郭清露 张会杰 《陕西水利》 2024年第6期15-18,22,共5页
为解决输水工程大型水池结构计算适用性问题,结合工程实例,采用通用有限元软件Midas Gen对某工程高位水池进行有限元分析,建立高位水池整体分析模型,得到高位水池在各种荷载工况及荷载组合下的变形及内力分布结果。针对水池不同部位,分... 为解决输水工程大型水池结构计算适用性问题,结合工程实例,采用通用有限元软件Midas Gen对某工程高位水池进行有限元分析,建立高位水池整体分析模型,得到高位水池在各种荷载工况及荷载组合下的变形及内力分布结果。针对水池不同部位,分析其水平向和竖直向弯矩,得出弯矩分布规律,用以进行针对性配筋设计。同时,内力结果不至过大,说明高位水池立柱和梁形成的纵、横向框架结构增强了水池的整体性和受力性能,结构体系是合理的。该计算实例可为类似工程设计提供参考。 展开更多
关键词 大型水池 结构计算 有限元 Midas gen
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Camilla Guerrieri’s Portrait of Guidobaldo II della Rovere:Symbols of Honor and Power
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作者 Liana De Girolami Cheney 《Journal of Literature and Art Studies》 2024年第8期641-659,共19页
The Altomani&Sons Collection owns a remarkable newly discovered portrait of Guidobaldo II della Rovere,Duke of Urbino(1514-1574),a historical military figure who was a condottiere,ruler of Urbino,Commander-in-chie... The Altomani&Sons Collection owns a remarkable newly discovered portrait of Guidobaldo II della Rovere,Duke of Urbino(1514-1574),a historical military figure who was a condottiere,ruler of Urbino,Commander-in-chief of the Papal Estate,and Perfect of Rome,as well as a collector and patron of the Fine Arts.Camilla Guerrieri Nati(1628-1694),a seventeenth-century Italian painter from Fossombrone(in the province of Pesaro and Urbino),portrayed this heroic personage surrounded by emblems associated with his military courage and leadership,including his plumed burgonet helmet,metal gilded armor,a necklace with the golden fleece,and batons of secular and religious dominions.This oil painting on copper-considered a precious metal at the time-emphasizes the importance of the commission.The material and technique also reveals a unique artistic achievement in that it provides the painting with a smooth,reflective surface and vibrant coloration,symbolizing precious imagery. 展开更多
关键词 Camilla Guerrieri Della Rovere Family Negroli Family Minerva Mars military portrait armor BATON helmet oil on copper dolphin and oak symbolism
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应用于ICS PCIE Gen2的扩频时钟模块电路
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作者 葛浩正 韩国旋 许培元 《信息技术与信息化》 2024年第3期162-165,共4页
为了满足ICS(internet connection sharing,因特网连接共享)PCIE Gen2协议,可提供输入时钟信号给PC、PCIE桥芯片以及以太网等芯片,利用时钟扩频技术的研究来减少系统的电磁干扰问题。基于应用于ICS PCIE Gen2协议的设计要求,通过采用SMI... 为了满足ICS(internet connection sharing,因特网连接共享)PCIE Gen2协议,可提供输入时钟信号给PC、PCIE桥芯片以及以太网等芯片,利用时钟扩频技术的研究来减少系统的电磁干扰问题。基于应用于ICS PCIE Gen2协议的设计要求,通过采用SMIC 0.18μm工艺设计传统锁相环结构,包括鉴频鉴相器、电荷泵、环路滤波器、环形振荡器、分频器以及相位插值器所设计的扩频时钟模块电路,实现了在满足指标400 MHz输出频率的基础上对扩频深度控制在-5×10-3以内,频谱峰值能量降低了10.32 dB,输出相位噪声在1 MHz频偏下为-107.378 dBc/Hz。未扩频模式下输出时钟的确定性抖动为31.6 ps,周期间RMS抖动为5.1 ps;进行扩频后,周期间RMS抖动为8.6 ps,满足了ICS PCIE Gen2的协议要求。 展开更多
关键词 ICS PCIE gen2协议 扩频时钟模块电路 电磁干扰 振荡器 相位插值器
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Coulter Gens血细胞分析仪白细胞分类失败常见原因分析及处理对策 被引量:3
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作者 梁伟 《淮海医药》 CAS 2007年第3期229-230,共2页
关键词 COULTER gens血细胞分析仪 白细胞分类失败 原因 对策
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COULTER GENS血细胞分析仪网织红细胞7项指标检测
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作者 李兴武 《郑州大学学报(医学版)》 CAS 北大核心 2009年第4期870-871,共2页
关键词 网织红细胞参数 gens血细胞分析仪 正常值
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应用MIDAS/GEN辅助“材料力学”课程的教学方法研究
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作者 张海涛 《安徽建筑》 2023年第10期128-129,132,共3页
“材料力学”课程在工科专业的课程体系中起着承上启下的作用,由于课程的特点和传统教学方法的不足,无论是教师讲授还是学生学习该课程都会遇到不少的困难。为提高“材料力学”课程的教学、学习效果,利用有限元软件辅助其教学是一条可... “材料力学”课程在工科专业的课程体系中起着承上启下的作用,由于课程的特点和传统教学方法的不足,无论是教师讲授还是学生学习该课程都会遇到不少的困难。为提高“材料力学”课程的教学、学习效果,利用有限元软件辅助其教学是一条可行的教学方法,有限元软件辅助教学的方法既可以用于课程的理论教学,又可以用于实验教学,并且已有不少学者先后进行了这方面的探索。MIDAS/GEN不仅具有优秀的建模和丰富结果查看功能,并且具有易学、易操作的特点,因此文章以MIDAS/GEN平台探索利用其辅助“材料力学”课程教学,并以具体举例形式说明该辅助教学方法的有益效果。 展开更多
关键词 MIDAS/gen 有限元软件 “材料力学” 教学方法
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Clostridium perfringens bacteremia caused by choledocholithiasis in the absence of gallbladder stones 被引量:11
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作者 Antwan Atia Tejas Raiyani +2 位作者 Pranav Patel Robert Patton Mark Young 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第39期5632-5634,共3页
A 67-years-old male presented with periumbilical abdominal pain, fever and jaundice. His anaerobic blood culture was positive for clostridium perfringens. Computed tomogram scan of the abdomen and abdominal ultrasound... A 67-years-old male presented with periumbilical abdominal pain, fever and jaundice. His anaerobic blood culture was positive for clostridium perfringens. Computed tomogram scan of the abdomen and abdominal ultrasound showed normal gallbladder and common bile duct (CBD). Subsequently magnetic resonance cholangiopancreaticogram showed choledocholithiasis. Endoscopic retrograde cholangiopancreaticogram-with sphincterotomy and CBD stone extraction was performed. The patient progressively improved with antibiotic therapy Choledocholithiasis should be considered as a source of clostridium perfringens bacteremia especially in the setting of elevated liver enzymes with cholestatic pattern. 展开更多
关键词 产气荚膜梭菌 胆总管结石 胆囊结石 梭状芽胞杆菌 血症 生物多样性公约 合并 抗生素治疗
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TOEPLITZ OPERATORS WITH POSITIVE OPERATOR-VALUED SYMBOLS ON VECTOR-VALUED GENERALIZED FOCK SPACES 被引量:2
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作者 陈建军 王晓峰 夏锦 《Acta Mathematica Scientia》 SCIE CSCD 2020年第3期625-640,共16页
In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson ... In this article,we study some characterizations of Toeplitz operators with positive operator-valued function as symbols on the vector-valued generalized Bargmann-Fock spaces Fψ^2.Main results including Fock-Carleson condition,bounded Toeplitz operators,compact Toeplitz operators,and Toeplitz operators in the Schatten-p class are all considered. 展开更多
关键词 Toeplitz operator operator-valued symbol generalized Fock space
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基于MIDAS Gen的多层钢筋混凝土框架结构倒塌数值模拟分析
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作者 郭隆基 何满潮 +4 位作者 瞿定军 李和安 陈翔 王国均 陶志刚 《科学技术与工程》 北大核心 2023年第14期6139-6147,共9页
汶川地震中大量钢筋混凝土(reinforced concrete,RC)框架结构破坏严重,极震区其倒塌率却远超过多层砖混结构。2022年9月以来,四川频发地震,为重新探讨倒塌机理及抗震性能,本文研究通过实地震害及多层RC框架结构破坏形式,结合数值模型并... 汶川地震中大量钢筋混凝土(reinforced concrete,RC)框架结构破坏严重,极震区其倒塌率却远超过多层砖混结构。2022年9月以来,四川频发地震,为重新探讨倒塌机理及抗震性能,本文研究通过实地震害及多层RC框架结构破坏形式,结合数值模型并应用MIDAS Gen有限元计算方法,研究了RC框架结构的倒塌机理、地震响应分析。结果表明:框架柱的破坏与屈服是RC框架倒塌的主要因素,模拟增设填充墙,当地震烈度达到10度时,层间位移角大约1/46,降低柱的轴压比,提高柱的破坏延性,增大结构的极限抗侧能力,起到抗震第一道防线的作用,避免整体屈服破坏。 展开更多
关键词 RC框架 倒塌机理 MIDAS gen 地震响应 填充墙
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Algorithm of symbol generation and configuration of land polygons in present land-use map
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作者 ZUO Xiao-qing, NIE Jun-tang Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期743-747,共5页
The symbolization of land polygon is an important part of cartography. In the mapping of traditional present land-use maps, the symbol of land polygons was usually filled by the method of filling or plotting, but thes... The symbolization of land polygon is an important part of cartography. In the mapping of traditional present land-use maps, the symbol of land polygons was usually filled by the method of filling or plotting, but these methods can't solve the spatial conflicts of the symbol. According to the principle of cartography, the rule of how to symbolize the land polygon was summarized, and a new method that can generate and deploy the land symbols was presented. By making use of C# programming language and Arc Engine developing components, the algorithm can generate land symbols presenting triangle and adjust the coordinate of the symbol. Through mapping the present land-use map of Honghe county, this algorithm can reduce 88.84% of the spatial conflicts error rate compared with the traditional methods. It improves the accuracy and efficiency of the map symbolic. 展开更多
关键词 LAND symbol PRESENT LAND use MAP symbol CONFIGURATION spatial conflict
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Analysis of convergence for initial condition estimation of coupled map lattices based on symbolic dynamics
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作者 孙丽莎 康晓云 林兰馨 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期179-186,共8页
A novel approach to the inverse problem of diffusively coupled map lattices is systematically investigated by utilizing the symbolic vector dynamics. The relationship between the performance of initial condition estim... A novel approach to the inverse problem of diffusively coupled map lattices is systematically investigated by utilizing the symbolic vector dynamics. The relationship between the performance of initial condition estimation and the structural feature of dynamical system is proved theoretically. It is found that any point in a spatiotemporal coupled system is not necessary to converge to its initial value with respect to sufficient backward iteration, which is directly relevant to the coupling strength and local mapping function. When the convergence is met, the error bound in estimating the initial condition is proposed in a noiseless environment, which is determined by the dimension of attractors and metric entropy of the system. Simulation results further confirm the theoretic analysis, and prove that the presented method provides the important theory and experimental results for better analysing and characterizing the spatiotemporal complex behaviours in an actual system. 展开更多
关键词 coupled mad lattices CONVERgenCE symbolic dynamics initial condition estimation
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Symbolic generation of the kinematics of multibody systems in EasyDyn: From MuPAD to Xcas/Giac
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作者 Olivier Verlinden Lassaad Ben Fkih Georges Kouroussis 《Theoretical & Applied Mechanics Letters》 CAS 2013年第1期89-94,共6页
In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position.... In the EasyDyn multibody open source project, computer algebra has been used from the beginning to generate the expressions of velocities and accelerations of the bodies, by symbolic differentiation of their position. Originally, the MuPAD computer algebra system had been retained because it was freely available for non commercial purposes and showed very good technical features.Unfortunately, MuPAD is nowadays only available through commercial channels and needs to be replaced to keep EasyDyn publicly available. This paper presents why Xcas/Giac is finally selected,among other long-term promising projects like Axiom, Maxima, Sage or Yacas. Among the choice criteria, the accessibility, the portability, the ease of use, the automatic export to C language, and the similarity with the -MuPAD language are all considered. The performances of the MuPAD and Xcas/Giac implementations are also compared on some examples.C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi:10.1063/2.13013012] 展开更多
关键词 symbolic multibody systems KINEMATICS computer algebra system open source
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COATES GRAPH APPROACH FOR GENERATING SYMBOLIC NETWORK FUNCTION
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作者 虞希清 陆生勋 《Journal of Electronics(China)》 1989年第4期378-385,共8页
In this paper, symbolic code matrix ,constant matrix and count matrix are defined .The first twomatrices are used to describe the elemental expression of augmented matrix and the nede admittance equa-tion is thus obta... In this paper, symbolic code matrix ,constant matrix and count matrix are defined .The first twomatrices are used to describe the elemental expression of augmented matrix and the nede admittance equa-tion is thus obtained. The third matrix is used to obtain the incoming degree matrix, and according to thematrix all the 1- factors of the Coates graph are given. By using the data code, the determinant is expandedand the same items in the expansion are merged. Thus the symbolic network function in which no term can-cellation occurs is generated. 展开更多
关键词 Linear NETWORK ANALYSIS symbolIC NETWORK function TOPOLOGICAL NETWORK ANALYSIS
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Improved Genetic Programming Algorithm Applied to Symbolic Regression and Software Reliability Modeling
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作者 Yongqiang ZHANG Huifang CHENG Ruilan YUAN 《Journal of Software Engineering and Applications》 2009年第5期354-360,共7页
The present study aims at improving the ability of the canonical genetic programming algorithm to solve problems, and describes an improved genetic programming (IGP). The proposed method can be described as follows: t... The present study aims at improving the ability of the canonical genetic programming algorithm to solve problems, and describes an improved genetic programming (IGP). The proposed method can be described as follows: the first inves-tigates initializing population, the second investigates reproduction operator, the third investigates crossover operator, and the fourth investigates mutation operation. The IGP is examined in two domains and the results suggest that the IGP is more effective and more efficient than the canonical one applied in different domains. 展开更多
关键词 IMPROVED genETIC PROGRAMMING symbolIC Regression SOFTWARE Reliability Model
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Design of high-performance ion-doped CoP systems for hydrogen evolution:From multi-level screening calculations to experiment 被引量:1
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作者 Xiaofei Cao Siqian Xing +6 位作者 Duo Ma Yuan Tan Yucheng Zhu Jun Hu Yao Wang Xi Chen Zhong Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期307-316,I0007,共11页
Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach... Rational design of high-performance electrocatalysts for hydrogen evolution reaction(HER)is vital for future renewable energy systems.The incorporation of foreign metal ions into catalysts can be an effective approach to optimize its performance.However,there is a lack of systematic theoretical studies to reveal the quantitative relationships at the electronic level.Here,we develop a multi-level screening methodology to search for highly stable and active dopants for CoP catalysts.The density functional theory(DFT)calculations and symbolic regression(SR)were performed to investigate the relationship between the adsorption free energy(ΔG_(H^(*)))and 10 electronic parameters.The mathematic formulas derived from SR indicate that the difference of work function(ΔΦ)between doped metal and the acceptor plays the most important role in regulatingΔG_(H^(*)),followed by the d-band center(d-BC)of doped system.The descriptor of HER can be expressed asΔG_(H^(*))=1.59×√|0.188ΔΦ+d BC+0.120|1/2-0.166 with a high determination coefficient(R^(2)=0.807).Consistent with the theoretical prediction,experimental results show that the Al-CoP delivers superior electrocatalytic HER activity with a low overpotential of75 m V to drive a current density of 10 mA cm^(-2),while the overpotentials for undoped CoP,Mo-CoP,and V-CoP are 206,134,and 83 m V,respectively.The current work proves that theΔΦis the most significant regulatory parameter ofΔG_(H^(*))for ion-doped electrocatalysts.This finding can drive the discovery of high-performance ion-doped electrocatalysts,which is crucial for electrocatalytic water splitting. 展开更多
关键词 Design of ion-doped catalyst symbolic regression Density functional theory calculation Hydrogen evolution reaction
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