摘要：The development of inexpensive and efficient Pt-free electrocatalysts for the hydrogen evolution reaction(HER)is greatly crucial for water *** carbide(WC)exhibiting a Pt-like electronic structure represents an attractive alternative,although its overall performance is limited by the strong W-H bond that impedes hydrogen ***,we employed an in-situ interface engineering strategy to construct high-performance and cost effective electrocatalysts comprising WC/tungsten phosphide(WP)heterostructures that were anchored on N,P-codoped carbon(WC/WP@NPC)via a one-step pyrolysis of a melamine polyphosphate/WO_(3) hybrid in an inert *** to the crystal structure compatibility and electron-rich property of WP,it optimizes the electronic structure and hydrogen adsorption configuration of WC,thus significantly weakening the W-H bond with a thermoneutral Gibbs free energy of hydrogen adsorption(ΔG_(H^(*)))of−0.05 ***,NPC ensures fast electron transport and structural stability of the WC/WP@NPC ternary *** synergistically lead to outstanding HER performances of the catalyst in acidic and alkaline *** finding offers a new strategy for designing Pt-alternative electrocatalysts with outstanding electrochemical performances for high-efficiency water splitting and other applications.

摘要：We propose a formation control strategy for multiple unmanned aerial vehicles （multi-UAV） based on second-order consensus, by introducing position and velocity coordination variables through neighbor-to-neighbor interaction to generate steering commands. A cooperative guidance algorithm and a cooperative control algorithm are proposed together to maintain a specified geometric configuration, managing the position and attitude respectively. With the whole system composed of the six-degree-of-freedom UAV model, tile cooperative guidance algorithm, and the cooperative control algorithm, the formation control strategy is a closed-loop one and with full states. The cooperative guidance law is a second-order consensus algorithm, providing the desired acceleration, pitch rate, and heading rate. Longitudinal and lateral motions are jointly considered, and the cooperative control law is designed by deducing state equations. Closed-loop stability of the formation is analyzed, and a necessary and sufficient condition is provided. Measurement errors in position data are suppressed by synchronization technology to improve the control precision. In the simulation, three-dimensional formation flight demonstrates the feasibility and effectiveness of the formation control strategy.

摘要：MXene is a variety of new two-dimensional(2D)materials with early transition metal carbides,nitrides,and *** chemical studies have been carried out on the geometries,electronic structures,stability and catalytic properties of a non-noble metal single-atom catalyst(SAC)with single Co atom anchored on MXene materials of Mo_(2)CS_(2).The Co adatom anchored on top of the Mo atom of this MXene is found to be rather stable,and this SAC is appropriate for CO *** charge transfers from the surface to the adsorbed CO and O2 play a significant role in the activation of these molecules on Co_(1)/Mo_(2)CS_(2).With this catalyst,the Eley-Rideal(ER),Langmuir-Hinshelwood(LH),and Termolecular Eley-Rideal(TER)mechanisms are explored for CO *** find that,while all the three mechanisms are feasible at low temperature,Co_(1)/Mo_(2)CS_(2) possesses higher catalytic activity for CO oxidation through the TER mechanism that features an intriguing OC(OO)CO intermediate(IM)adsorbed on Co single *** calculated activation energy barriers of the rate-limiting step are 0.67 eV(TER),0.78 eV(LH)and 0.88 eV(ER),*** present study illustrates that it is promising to develop and design low-cost,non-noble metal SACs using MXene types of 2D materials.

摘要：为了建立一个面向用户、设计师、工程师和决策者的产品设计知识协同信息管理平台,有效利用案例中的设计知识,提出一种案例驱动的协同设计知识管理模型,该模型通过分析新产品开发中用户、决策者、设计师和工程师之间的设计知识流通模式,建立了基于案例的知识协同与信息交互过程的映射模型,提出了基于Markov模型的设计知识提取方法,构建了案例驱动的协同设计知识管理框架,并以软件形式实现。案例驱动的协同设计知识管理模型将已有领域案例的设计知识引入新项目设计问题的设计求解中,新产品设计开发和过程管理所需的所有设计信息均可通过领域案例设计知识库进行实时地设计知识获取、重用和进化,直至完成整个设计项目。以某品牌起重机造型设计方案在案例驱动协同设计知识管理软件平台上的具体应用为例进行验证,证明了所提模型的可行性和合理性。

摘要：摩擦发光(ML)是由机械力作用在材料上引起的发光现象。近年来,金属配合物ML材料因其独特的光学发射特性而受到广泛关注,在应力传感、防伪、结构健康监测、医疗健康、结构检测等领域有着广阔的应用前景。本文综述了近年来具有摩擦发光性质的金属配合物材料的研究进展,包括镧系金属配合物和过渡金属配合物。此外,还讨论了摩擦发光的产生机制、设计原理、光物理性质及其应用前景。本综述将为构建金属配合物摩擦发光材料以及拓展其在应力传感、结构检测等方面的应用提供启发和指导。

摘要：电流互感器(current transformer,CT)的暂态饱和容易导致继电保护误动作,寻求暂态饱和的原因和防范保护误动的对策特别需要建立CT的分析模型,然而该模型及其参数的构建如何体现实际运行一直是个研究难点。该文首先基于J-A理论给出了CT分析模型,分析了该模型的数值计算思路。然后针对J-A模型中描述不同励磁曲线轨迹的关键参数,研究了以磁感应强度B为优化目标的引力搜索辨识方法。最后,精心设计了330k V系统P级CT的6~48k A大通流动态模拟试验,测试表明CT的J-A模型以及所提的参数辨识算法是有效的、正确的并且符合工程实际。

摘要：大力推进材料和装备的轻量化、减量化是实现节能减排、加快建设节约型社会的关键措施,是新世纪工程科技的发展方向。大至海洋平台、大飞机机身和动车组车体,再到日常生活中的车辆,乃至小电子散热器件等,轻量化和多功能化均成为其发展中重要一环。围绕相关特殊工况应用条件下的轻质材料与结构的设计和研究面临一系列挑战:质量轻、力学强度高、散热性能好、动力学性能和隔振、隔声性能可调等多功能要求,因此如何在现有的材料和结构基础上进一步减轻重量并获得更优良的综合性能是材料科学、固体力学、传热、声学、优化设计等诸多领域工作者面临的共同挑战。基于本课题组近5年来围绕"超轻多孔结构创新构型的多功能化基础研究"国家基础研究计划项目所开展的一系列工作,综述了国内超轻多孔材料与结构最新发展水平的研究成果,总结了具有特定或多功能化应用的这类新型轻质多孔材料多学科交叉研究的进展,包括材料制备,力学、热学和声学特性,以及无损检测及优化设计等。