检索结果-南通市图书馆

Science China Materials 2025年第1期68卷 173-179页

作者： Yongxia Shi Junjun Li Zhiwen Min Xinyi Wang Man Hou Hao Ma Zechao Zhuang Yuchen Qin Yuanmiao Sun Dingsheng Wang zhicheng zhang Key Laboratory of Organic Integrated Circuit Ministry of Education&Tianjin Key Laboratory of Molecular Optoelectronic SciencesDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Faculty of Materials Science and Energy Engineering/Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Department of Chemistry Tsinghua UniversityBeijing 100084China College of Sciences Henan Agricultural UniversityZhengzhou 450000China

Rationally modulating the adsorption configuration of the key*CO intermediate could facilitate carbon±carbon(C±C)coupling to generate multi-carbon products in the electrochemical CO_(2) reduction *** this work,theoretical calculations reveal that C±C coupling via atopadsorbed*CHO and hollow-adsorbed*CO over Cu sites is an energetically favorable *** a proof of concept,a tandem trimetallic AuAgCu heterojunction(Au@Ag/Cu)was prepared,where the atop-adsorbed*CO over Au@Ag sites could migrate to Cu sites with hollow adsorption configuration,and then the asymmetric C±C coupling via transferred hollow-adsorbed*CO and existed atop-adsorbed*CHO over Cu sites facilitates the formation of the ethanol product,exhibiting a maximum Faraday efficiency of 65.9%at a low potential of−0.3 V *** hydrogen *** work provides new insights into the intrinsic understanding of tandem catalysis by regulating adsorption configuration of the intermediate products.

关键词： CO_(2)electroreduction C–C coupling tandem catalysis adsorption configuration ethanol

Achievements, challenges and opportunities in hydrogen production fromwater/seawater splitting using boron-based materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Materials 2025年第2期68卷 341-363页

作者： Yiran zhang Yang Xu Qi Zhou Junjun Li Xinyi Wang Zhenwei Zhao zhicheng zhang Key Laboratory of Organic Integrated Circuits Ministry of Education&Tianjin Key Laboratory of Molecular Optoelectronic SciencesDepartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Department of Chemistry Tsinghua UniversityBeijing 100084China

Water splitting is recognized as an environmentally friendly and feasible method to produce ***, the high cost, low storage capacity, and poorstability of traditional noble metal-based electrocatalysts haveseverely limited the industrial application of electrocatalyticwater splitting. The utilization of seawater splitting not onlyfacilitates the production of high-purity hydrogen on a largescale but also concurrently promotes the desalination *** the past decades, transition metal borides (TMBs) havebeen widely used in the field of water splitting due to theadvantages of simple preparation process, good stability, andeasily adjustable composition. This review summarizes therecent progress of TMBs in the electrolysis of water and ***, the influencing factors of electrocatalytic performance and related evaluations are introduced. The basicprinciples of hydrogen evolution reaction, oxygen evolutionreaction, and chlorine evolution reaction in seawater electrolysisare discussed in detail, pointing out the various problemscaused by chloride ions (Cl^(−)) in the process of hydrogenproduction from seawater splitting. In addition, the preparation and optimization strategies of TMBs are ***, the development, challenges, and prospects of electrolytic seawater hydrogen production technology are presented. This review aims to furnish deeper insights intoenhancing the electrocatalytic performance of TMBs in thiscritical area of research.

关键词： water/seawater splitting transition metal borides hydrogen production

同方期刊数据库

在线全文

学校读者我要写书评

暂无评论

面向集群卫星分布式定时组网的协同编队技术

航空学报 2025年第4期46卷 278-288页

作者：张志成周媛赵宇包为民中国航天科技创新研究院北京100871 北京大学工学院北京100176 西北工业大学自动化学院西安710129 中国航天科技集团有限公司科学技术委员会北京100048

随着日趋增长的空间信息需求,卫星编队控制技术迅猛发展。传统的研究理论仅关注系统三维状态收敛特性,无法从时间维度对编队进行有效控制,而星间激光通讯技术对卫星编队形成的时效性和准确性提出了较高的要求。针对地球同步轨道运行的... 详细信息

随着日趋增长的空间信息需求,卫星编队控制技术迅猛发展。传统的研究理论仅关注系统三维状态收敛特性,无法从时间维度对编队进行有效控制,而星间激光通讯技术对卫星编队形成的时效性和准确性提出了较高的要求。针对地球同步轨道运行的卫星系统预定时间编队控制问题,引入含参Lyapunov方程将预定时间控制转化为时变参数设计问题,提出了动态增益调节的编队策略和自适应编队策略。仿真结果表明,卫星系统可在任意预定时间内自主地实现编队构型建立、切换和保持,为实际工程中星间激光信号传输的稳定性提供了可靠保证。

关键词：集群卫星系统星间激光建链编队控制预定时间组网自适应控制系统

Insight into the Effect of Metal Cations in the Electrolyte on Performance for Electrocatalytic CO_(2)Reduction Reaction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2022年第4期5卷 1008-1009页

作者： Junjun Li zhicheng zhang Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin 300072China

This highlight indicates that the local electrostatic interactions between metal cations and key intermediates facilitate the electrocatalytic CO_(2) reduction *** CO_(2) reduction reaction(CO_(2)RR)has been considere... 详细信息

关键词： CO_(2)reduction reaction electrocatalysis metal cations

Application of Artificial Bee Colony Algorithm to Maximum Likelihood DOA Estimation

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2013年第1期10卷 100-109页

作者： zhicheng zhang Jun Lin Yaowu Shi College of Communication Engineering Jilin University Changchun 130012 P. R. China College of Instrumentation & Electrical Engineering Jilin University Changchun 130061 P. R. China

Maximum Likelihood （ML） method has an excellent performance for Direction-Of-Arrival （DOA） estimation, but a mul- tidimensional nonlinear solution search is required which complicates the computation and prevents the method from practical use. To reduce the high computational burden of ML method and make it more suitable to engineering applications, we apply the Artificial Bee Colony （ABC） algorithm to maximize the likelihood function for DOA estimation. As a recently proposed bio-inspired computing algorithm, ABC algorithm is originally used to optimize multivariable functions by imitating the be- havior of bee colony finding excellent nectar sources in the nature environment. It offers an excellent alternative to the con- ventional methods in ML-DOA estimation. The performance of ABC-based ML and other popular meta-heuristic-based ML methods for DOA estimation are compared for various scenarios of convergence, Signal-to-Noise Ratio （SNR）, and number of iterations. The computation loads of ABC-based ML and the conventional ML methods for DOA estimation are also investi- gated. Simulation results demonstrate that the proposed ABC based method is more efficient in computation and statistical performance than other ML-based DOA estimation methods.

关键词： DOA estimation maximum likelihood artificial bee colony algorithm bio-inspired computing

Influences of Environmental Motion Modes on the Efficiency of Ultrathin Flexible Piezoelec trie Energy Harvesters

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2019年第5期32卷 611-620页

作者： Chaofeng Lii Yangyang zhang He zhang zhicheng zhang Yisheng Chen College of Civil Engineering and Architecture Zhejiang University310058 HangzhouPeople Republic of China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University310027 HangzhouPeople's Republic of China Soft Matter Research Center Zhejiang University310027 HangzhouPeople's Republic of China

Harvesting energy from ambient vibration sources with ultrathin flexible piezoelectric energy harvesters(PEHs)for battery-free electronics has received attention in recent ***,the excitation modes in the environment and human body motion are more complicated than the ideal harmonic modes employed in previous theoretical analyses,and their influence on the efficiency of PEHs has received little *** this study,these environmental excitation modes are classified into three types,i.e.,the triangular,sinusoidal,and square wave modes,with varied duty *** derived theoretically the output power of flexible PEHs under these excitation modes and establish a simple scaling law,in which the normalized output power depends only on two combined normalized parameters,i.e.,the intrinsic system parameter and the excitation *** reveal that the output power of PEHs changes dramatically for different excitation modes with varied duty ratios even when all the other parameters including excitation ampli tude,excitation frequency,elec trical parameter,and geometrical and material parameters of the PEHs are *** paper may provide a systematic understanding in the effect of exc计ation modes on the output power of flexible PEHs and promote the realization of energy harvesting from the complex environmental and human body motions.

关键词： Flexible piezoelec trie energy harves ter Environmental excitation modes Energy harvesting efficiency Theoretical predictions Scaling law

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao Qi Jianqin Yin zhicheng zhang Jin Tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Exclusive CO_(2)-to-formate conversion over single-atom alloyed Cu-based catalysts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Green Energy & Environment 2022年第5期7卷 855-857页

Electrochemical CO_(2) reduction reaction(CO_(2) RR),powered by renewable energy sources,provides an appealing approach to convert emitted CO_(2) to value-added chemicals and fuels and achieve a carbon-neutral *** various carbon-based products,formic acid(HCOOH) has been considered as a promising liquid hydrogen storage material due to its high energy density and hydrogen ***,so far,the reported HCOOH-selective catalysts(e.g.,Bi,Sn,In,Pb and Pd) have failed in either activity(<500 mA cm^(-2)) or stability(<20 h),which significantly inhibits the industrialized feasibility of CO_(2) *** contrast,Cu takes the advantages of excellent activity and low cost,making it more commercially *** date,one of the most challenging issues of Cu-based catalysts lies in unsatisfactory selectivity,that is,tending to produce mixed products rather than specific one,due to the complicated reaction paths *** recently,Zheng et *** developed a single-atom alloy(SAAs) strategy for the exclusive CO_(2)-to-formate conversion over Cu-based *** as-prepared Pb single-atom alloyed Cu catalyst(Pb_(1)Cu)(***) exhibited near unity selectivity towards HCOOH and impressive stability,providing the prospect of industrial production of HCOOH from CO_(2).

关键词： selectivity stability neutral

Inorganic nanocrystals:From molecular design to systematic engineering

在线全文

学校读者我要写书评

暂无评论

Particuology 2014年第6期12卷 1-10页

作者： Kai Wang zhicheng zhang Xun Wang Yadong Li Department of Chemistry Tsinghua University

Solution-based routes have been widely applied in the synthesis of *** is desirable to choose or design precursors,ligands,and solvent molecules at the molecular level to allow the synthesis of lowdimensional nanocrystals with various shapes and *** increasing requirements for the integration of the properties of nanocrystals have produced a high demand for the rational design and fine control of complex structures,in terms of both the composition and the *** meet this demand,researchers have developed new synthetic strategies to produce more complex and more functional *** procedures involve systematic engineering,which focuses on the whole synthetic procedure,instead of just the molecular *** review focuses mainly on the work of Yadong Li’s group over the last decade.

关键词： Molecular design Systematic engineering Synthesis Nanocrystal

Recent advances in carbon-based materials for electrochemical CO_(2) reduction reaction

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2022年第5期33卷 2270-2280页

作者： Zengqiang Gao Junjun Li zhicheng zhang Wenping Hu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of Science&Collaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China

The increase of atmospheric CO_(2)concentration has caused many environmental ***-cal CO_(2)reduction reaction(CO_(2)RR)has been considered as a promising strategy to mitigate these *** electrocatalysts with a low overpotential,high Faradaic efficiency,and excellent selectivity are of great significance for the CO_(2)***-based materials including metal-free carbon catalysts and metal-based carbon catalysts have shown great potential in the CO_(2)RR,owing to the tailorable porous structures,abundant natural resources,resistance to acids and bases,high-temperature stability,and en-vironmental *** this review,various carbon materials including graphene,carbon nanotubes,quantum dots,porous carbon,and MOF-derived catalysts,etc.,for the CO_(2)RR have been ***,recent progress in terms of the mechanism and pathway of CO_(2)conversion has been com-prehensively ***,the opportunities and challenges of carbon-based electrocatalysts for the CO_(2)RR are proposed.

关键词： CO_(2)reduction Electrocatalysis Carbon materials Chemicals and fuels Single-atom catalysts