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Breaking the Scaling Relationship limit:From Single-Atom to Dual-Atom Catalysts

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Accounts of Materials Research 2022年第6期3卷 584-596页

作者： longbin li Kai Yuan Yiwang Chen Institute of Polymers and Energy Chemistry(IPEC) College of Chemistry and Chemical EngineeringNanchang UniversityNanchang 330031China National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang 330022China

Recent decades have witnessed the rapid development of catalytic science,especially after Taylor and Armstrong proposed the notion of the“active site”in *** optimizing reaction paths and reducing the activation energies of reactions,catalysts appear in more than 90%of chemical production reactions,involving homogeneous catalysis,heterogeneous catalysis,and enzyme *** of the 100%efficiency of active atom utilization and the adjustable microenvironment of metal centers,single-atom catalysts(SACs)shine in various catalytic fields for enhancing the rate,conversion,and selectivity of chemical ***,a solo active site determines a fixed adsorption mode,and the adsorption energies of intermediates from multistep reactions linking with a solo metal site are related to each *** a specific multistep reaction,it is almost impossible to optimally adjust the adsorption of every intermediate on the solo site *** phenomenon is termed the scaling relationship limit(SRL)and is an unavoidable obstacle in the development of pure ***-atom catalysts(DACs),perfectly inheriting the advantages of SACs,can exhibit better catalytic performance than simple SACs and thus have gradually gained researchers’*** on the dual-metal structure,dual-metal sites(DMSs)in DACs can be divided into two separated heterometal sites,two linked homometal sites,and two linked heterometal *** separated heterometal sites prescribe a distance limit between two metal sites for electron ***,the active origins of DACs can be summarized in the following three points:(1)electronic effect,in which only one metal center serves as active site and the other plays an electronic regulatory role;(2)synergistic effect,in which two metal centers separately catalyze different core steps to improve catalytic performance together;(3)adsorption effect,in which offering additional sites changes the adsorption structures to break the

关键词： catalysis adsorption summarized

Molecular crowding agents engineered to make bioinspired electrolytes for high-voltage aqueous supercapacitors

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eScience 2021年第1期1卷 83-90页

作者： Mengke Peng li Wang longbin li Zhongyou Peng Xiannong Tang Ting Hu Kai Yuan Yiwang Chen College of Chemistry/Institute of Polymers and Energy Chemistry Nanchang University999 Xuefu AvenueNanchang330031China Institute of Advanced Scientific Research(iASR) Key Laboratory of Functional Small Molecules for Ministry of EducationJiangxi Normal University99 Ziyang AvenueNanchang330022China

The development of low-cost and eco-friendly aqueous electrolytes with a wide voltage window is the key to achieving safe high energy density supercapacitors(SCs).In this work,a molecular crowding electrolyte is prepared by simulating the crowded environment in living *** transport in the molecular crowding electrolyte can be effectively improved via reducing the molecular weight of the crowding agent,polyethylene glycol(PEG).The results show that PEG with a molecular weight of 200(PEG200)can significantly improve ionic conductivity while maintaining a wide voltage *** advantages enable commercial activated carbon-based SCs to work at 2.5 V with high energy density,outstanding rate performance and good stability for more than 10,000 *** this basis,three series of molecular crowding electrolytes using sodium perchlorate,lithium perchlorate,and sodium trifluoromethanesulfonate as salts are developed,demonstrating the versatility of PEG200 for wide-voltage aqueous electrolytes.

关键词： Supercapacitor Electrolytes Molecular weight Ionic conductivity Electrochemical energy storage

Arranging Electronic Localization of PtCu Nanoalloys to Stimulate Improved Oxygen Electroreduction for High-Performance Fuel Cells

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CCS Chemistry 2023年第11期5卷 2545-2556页

作者： Bing Wu Jiayong Xiao longbin li Ting Hu Ming Qiu Dirk Lützenkirchen-Hecht Kai Yuan Yiwang Chen Institute of Polymers and Energy Chemistry College of Chemistry and Chemical EngineeringNanchang UniversityNanchang 330031 School of Physics and Materials Science Nanchang UniversityNanchang 330031 Central China Normal University Wuhan 430079 Faculty of Mathematics and Natural Sciences-Physics Department Bergische Universität WuppertalWuppertal D-42119 National Engineering Research Center for Carbohydrate Synthesis/Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang 330022

Developing exceptionally durable and efficient oxygen reduction reaction(ORR)catalysts is of paramount importance to the widespread commercialization of proton exchange membrane fuel cells(PEMFCs)but is still ***,PtCu nanoalloys rooted on nitrogen-doped carbon nanosheets(PtCuNC-700)with fully exposed PtCu nanoalloys and strong metal–support interaction were *** from its structural and compositional merits,PtCuNC-700 showcases superior ORR activity and stability with a specific activity of 1.05mA cm^(−2)and mass activity of 0.45 A mgPt^(−1),4.2-fold and 3.7-fold higher than Pt/C(0.25 mA cm^(−2)and 0.12 A mgPt^(−1)),***,PtCuNC-700 exhibits first-class performance in H2/air PEMFC assessment and delivers a peak power density of 929.7 mW cm^(−2)and excellent cycling stability up to 30,000 *** calculations disclose that the synergistic effect of alloying Pt with Cu combined with the strong interaction between PtCu nanoalloys and nitrogen-doped carbon nanosheets can effectively modify the local electron configuration and density of states of Pt sites approaching the Fermi ***,the PtCu-alloy catalysts realized here diminish the energy barrier for ORR and accelerate their reaction *** work provides a reliable and effective approach to boost the activity and stability of Pt alloy-based ORR electrocatalysts in PEMFCs.

关键词： PtCu nanoalloy strong metal-support interaction stability oxygen reduction reaction fuel cells

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采用超节点协同的多智能体系统一致性算法

信息与控制 2019年第6期48卷 694-699,706页

作者：李龙斌桂林电子科技大学信息与通信学院广西桂林541004

针对如何提高多智能体系统达到一致性的收敛速度的问题,提出了一种采用超节点协同的多智能体系统一致性算法.新算法对多智能体系统建立图信号模型,在图中选出超节点进行协同,有效提高一致性收敛速度.首先利用单跳采样算法对图进行超节... 详细信息

针对如何提高多智能体系统达到一致性的收敛速度的问题,提出了一种采用超节点协同的多智能体系统一致性算法.新算法对多智能体系统建立图信号模型,在图中选出超节点进行协同,有效提高一致性收敛速度.首先利用单跳采样算法对图进行超节点的选取和局部集的划分,并对局部集内的节点进行一次协同.然后超节点之间进行边的连接得到粗化图,用粗化图的拉普拉斯矩阵特征值设计图滤波器的系数.最后超节点的信号经过图滤波器迭代达到平均值后,传输给其一阶邻居节点,使所有节点达到平均一致.仿真结果表明所提算法能够最终实现平均一致性,与现有方法相比,可以显著提高收敛速度,并减少计算量.

关键词：多智能体系统平均一致性图信号超节点粗化图

Decrypting the Influence of Axial Coordination on the Electronic Microenvironment of Co-N_(5)Site for Enhanced Electrocatalytic Reaction

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CCS Chemistry 2023年第8期5卷 1876-1887页

作者： Bingyu Huang Senhe Huang Chenbao Lu longbin li Judan Chen Ting Hu Dirk Lützenkirchen-Hecht Kai Yuan Xiaodong Zhuang Yiwang Chen Institute of Polymers and Energy Chemistry(IPEC) College of Chemistry and Chemical EngineeringNanchang UniversityNanchang 330031 The meso-Entropy Matter Lab School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240 School of Materials Science and Engineering Nanchang UniversityNanchang 330031 Faculty of Mathematics and Natural Sciences-Physics Department Bergische Universität WuppertalWuppertal D-42119 Institute of Advanced Scientific Research(iASR) Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal UniversityNanchang 330022

Metal porphyrins are star molecules that possess welldefined coordination metal centers for versatile catalytic ***,most previous work has focused on the correlations between in-plane symmetric configuration of metal-N_(4)sites and their catalytic *** the catalytic contribution of additional axial coordination to such symmetric configuration remains a *** calculations revealed that axially anchoring an extra pyridine on the tetra-coordinated cobalt porphyrin(Co-N4)to construct penta-coordinated cobalt porphyrin(Co-N_(5))renders cobalt a higher electron density,thereby favoring the rate-determining O_(2)adsorption/activation and reducing the oxygen electroreduction ***,a well-defined Co-N_(5)site is rationally introduced into the azo-linked polymer framework for a fundamental structure-catalytic performance correlation ***-prepared Co-N_(5)catalyst exhibits a 26 mV positive shift in half-wave potential compared with the pyridine-free Co-N_(4)counterpart,discloses a markedly higher power density(141.4 mW cm^(−2)),and possesses better long-term durability(over 160 h cycles)in a Zn-air ***,such a Co-N_(5)catalyst also showcases potential applications for CO_(2)reduction with high CO_(2)-to-CO conversion faradic efficiency and better selectivity than the Co-N_(4)counterpart because coordination of the fifth pyridine evokes electronic localization that suppresses a competitive side *** work proves the positive electrocatalytic contribution of axial penta-coordination on well-defined metalporphyrin-based catalysts and offers atomic understanding of the structure-performance correlation on single atom catalysts for future catalyst design.

关键词： porphyrin axial coordination pentacoordination structureactivity correlation oxygen reduction reaction

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国外大型桥梁支座修复施工技术

工程建设 2023年第5期55卷 49-56页

作者：李龙彬山东水利建设集团有限公司山东济宁272021

及时进行桥梁支座病害整治有利于提高桥梁养护水平,有效延长桥梁使用寿命。本文以中东地区某大型市政桥梁修复工程为例,对在不中断交通的情况下的桥梁支座修复施工成套技术进行介绍。通过项目特点分析和方案比选,详细论述了桥梁同步顶... 详细信息

及时进行桥梁支座病害整治有利于提高桥梁养护水平,有效延长桥梁使用寿命。本文以中东地区某大型市政桥梁修复工程为例,对在不中断交通的情况下的桥梁支座修复施工成套技术进行介绍。通过项目特点分析和方案比选,详细论述了桥梁同步顶升、超高压水射流设备混凝土拆除、支座混凝土恢复压浆的工艺原理和操作要点,此套工艺具有技术先进、质量可靠、施工快速、安全环保的显著优势。本文内容可为国内类似工程提供一些借鉴和指导。

关键词：桥梁支座修复工艺同步顶升支座拆除海外工程

建设用地地下水有机物污染检测与治理策略研究

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当代化工研究 2024年第17期 104-106页

作者：李龙彬深圳市北研生态环境科技有限公司广东518000

本文旨在探讨建设用地地下水有机物污染的检测技术与治理方法,针对当前城市化进程中工业活动、农业面源污染及生活污水排放导致的地下水有机物污染问题,系统分析了有机污染物的种类、来源及其对环境和人体健康的潜在威胁。在建设用地地... 详细信息

本文旨在探讨建设用地地下水有机物污染的检测技术与治理方法,针对当前城市化进程中工业活动、农业面源污染及生活污水排放导致的地下水有机物污染问题,系统分析了有机污染物的种类、来源及其对环境和人体健康的潜在威胁。在建设用地地下水有机物污染检测过程中,常用的检测方法包括荧光光谱、红外光谱、拉曼光谱等常规分析监测技术,以及气质联用、液质联用、液相总有机碳分析仪、傅里叶变换共振回旋离子质谱仪等先进手段。基于这些先进的检测技术,能够更进一步的对城市建设地下水污染问题全面地分析,从而提出针对性的治理改善对策,以期为更进一步推动城市向着良好的方向发展提供基础性保障。

关键词：建设用地地下水有机物污染检测治理

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基于深度学习的钨钼找矿靶区预测方法研究

地球信息科学学报 2019年第6期21卷 928-936页

作者：蔡惠慧朱伟李孜轩刘园园李龙斌刘畅中国地质大学(北京) 北京100083 中国地质调查局发展研究中心北京100037 陕西省矿产地质调查中心西安710068 中国地质大学(武汉)信息工程学院武汉430074 中国地质大学(武汉)国家地理信息系统工程技术研究中心武汉430074

随着矿产勘查工作由浅部矿向深部隐伏矿、由易识别矿向难识别矿发展,找矿难度日益增大,地质专家越来越重视新理论、新方法、新技术的应用。深度学习作为人工智能的前沿领域/技术,对于实现矿产资源预测'智能化预测评价'具有得天独厚的优... 详细信息

随着矿产勘查工作由浅部矿向深部隐伏矿、由易识别矿向难识别矿发展,找矿难度日益增大,地质专家越来越重视新理论、新方法、新技术的应用。深度学习作为人工智能的前沿领域/技术,对于实现矿产资源预测'智能化预测评价'具有得天独厚的优势。本文以陕西省镇安县西部钨钼矿集区单元素化探异常原始数据为基础,提出了基于深度学习的钨钼矿产评价方法。该方法以归一化地球化学数据作为模型训练数据,通过深度学习中深度自编码网络方法实现异常值提取进而识别重点成矿有利地段,实现矿产资源找矿远景区定性预测。研究结果表明,在对957条单元素化探异常原始数据分类且做好模型标签后,整个过程在计算机的'黑盒子'中自动完成学习和预测,相较于传统预测研究方法,本文方法具有自动化程度高和客观性强的特征。此外,本文利用已知矿点构建训练数据集,采用随机森林方法对预测区进行矿产资源找矿靶区预测圈定,为进一步缩小找矿靶区范围提供科学依据。

关键词：随机森林方法深度学习钨钼多金属矿产资源大数据预测评价陕西镇安西部

内镜下负压套扎术联合硬化剂注射治疗内痔出血的疗效及术后并发症危险因素

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中国临床研究 2024年第11期37卷 1735-1739页

作者：沈宝龙栾晓琳李龙彬任斌山东第二医科大学山东潍坊262100 安丘市人民医院山东潍坊262100 山东第二医科大学附属医院山东潍坊262100

目的探讨内镜下负压套扎术联合硬化剂注射治疗内痔出血的临床疗效,并分析术后并发症危险因素。方法选取安丘市人民医院肛肠外科2021年3月至2023年3月收治的Ⅱ~Ⅲ度内痔患者210例,按数字表法随机分为对照组(105例)和联合组(105例),对照... 详细信息

目的探讨内镜下负压套扎术联合硬化剂注射治疗内痔出血的临床疗效,并分析术后并发症危险因素。方法选取安丘市人民医院肛肠外科2021年3月至2023年3月收治的Ⅱ~Ⅲ度内痔患者210例,按数字表法随机分为对照组(105例)和联合组(105例),对照组采用内镜下负压套扎术治疗,联合组采用内镜下负压套扎术联合硬化剂注射治疗,比较两组患者手术治疗疗效及术后并发症发生情况。根据术后并发症发生情况分为并发症组和无并发症组,采用logistic多因素回归分析患者术后发生并发症的危险因素。结果联合组总有效率高于对照组,差异有统计学意义(97.14%vs 86.67%,P<0.05)。联合组手术时间长于对照组,术中出血量低于对照组,内痔脱落时间及住院时间均短于对照组,并发症总发生率低于对照组,差异有统计学意义(P<0.05)。Logistic多因素回归分析显示,年龄≥50岁、病程≥1年、内痔程度Ⅲ度、辛辣饮食、内痔脱落时间≥7 d、首次排便时间<24 h均为内痔术后发生并发症的独立危险因素(P<0.05)。结论内镜下负压套扎术联合硬化剂注射治疗内痔临床效果较好,并发症发生率较低,高龄、病程长、内痔脱垂程度严重、辛辣饮食、内痔脱落时间长、首次排便时间过早均为内痔术后并发症的危险因素,临床应针对以上危险因素制定有效干预措施,以提升手术治疗效果。

关键词：负压套扎术硬化剂内痔并发症危险因素