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Frontiers in Energy 2024年第4期18卷 525-534页

作者： Juntian NIU Shengzhuo CHEN Xianrong ZHENG Haiyu LIU Yan JIN jingyu ran College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Low-grade Energy Utilization Technologies and Systems(Ministry of Education) Chongqing UniversityChongqing 400044China

In recent years,the dry reforming of methane(DRM)reaction has gained widespread attention due to its effective utilization of two major greenhouse *** Ni-based catalysts for DRM exhibit a strong dependence on particle size,however,the reaction mechanisms involved remain *** this work,the effect of metal particle size on CO_(2)activation and CO formation was explored in the DRM reaction using the density functional ***/MgO(x=13,25,37)was constructed to investigate the CO_(2)activation and the formation of CO during the DRM *** is found that CO_(2)is more inclined to undergo chemisorption on Nix/MgO before *** the variation in particle size,the main activation pathway of CO_(2)on the catalyst *** the smallest Ni13/MgO,CO_(2)tends to directly dissociate,while on the larger Ni25/MgO and Ni37/MgO,the hydrogenation dissociation of CO_(2)is more kinetically *** to Ni13/MgO and Ni37/MgO,the oxidation of surface C atoms and the oxidation of CH occur more readily on Ni25/*** indicates that C atoms are less likely to form on Ni25 particle and are more easily to be *** some extent,the results suggest that Ni25/MgO exhibits superior resistance to carbon formation.

关键词： particle size Ni/MgO catalyst CO_(2)activation CO formation

Co-Ni/MgO催化剂上低温甲烷二氧化碳干重整研究

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工程热物理学报 2024年第6期45卷 1735-1742页

作者：杨桐冉景煜黄鑫欧志良邱华禹重庆大学能源与动力工程学院低品位能源利用技术及系统教育部重点实验室重庆400044

采用溶胶凝胶法制备Ni/MgO和Co-Ni/MgO催化剂,考察了催化剂在甲烷二氧化碳低温干重整反应中的性能。结果表明1%Co-10%Ni/Mg O催化剂拥有较高的CH_(4)、CO_(2)转化率以及最高的H_(2)/CO,且在450℃下反应20 h后该催化剂的CH_(4)、CO_(2)... 详细信息

采用溶胶凝胶法制备Ni/MgO和Co-Ni/MgO催化剂,考察了催化剂在甲烷二氧化碳低温干重整反应中的性能。结果表明1%Co-10%Ni/Mg O催化剂拥有较高的CH_(4)、CO_(2)转化率以及最高的H_(2)/CO,且在450℃下反应20 h后该催化剂的CH_(4)、CO_(2)转化率以及H_(2)/CO仍高于Ni/Mg O催化剂,且积碳量比Ni/MgO催化剂少4.3%。通过XRD、H_(2)-TPR、TEM、SEM、TG、RAMAN等表征分析发现适量Co的添加有利于提升催化剂表面活性组分的分散度和粒径,减少催化剂颗粒的团簇,且能抑制积碳的形成。通过对干重整反应过程中反应物表观活化能的计算,发现适量Co的添加能降低反应物的表观活化能,有利于提升Ni/MgO催化剂的低温甲烷干重整反应性能。

关键词：镍钴氧化镁低温干重整积碳

ABO_(3)载氧体A/B位金属对乙烷化学链氧化制乙烯性能影响实验研究

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中国电机工程学报 2024年第15期44卷 6086-6094,I0021页

作者：杨仲卿牛浩男唐波李秀权冉景煜低品位能源利用技术及系统教育部重点实验室(重庆大学) 重庆市沙坪坝区400044 重庆大学能源与动力工程学院重庆市沙坪坝区400044

钙钛矿载氧体因其低廉的成本、A/B位掺杂金属的灵活多变、优良的氧储存释放性能而受到关注,被广泛应用于化学链式氧化反应中制备乙烯。该文采用柠檬酸络合法制备不同A/B位金属的ABO_(3)钙钛矿型载氧体,通过研究A/B位金属变化对乙烷催化... 详细信息

钙钛矿载氧体因其低廉的成本、A/B位掺杂金属的灵活多变、优良的氧储存释放性能而受到关注,被广泛应用于化学链式氧化反应中制备乙烯。该文采用柠檬酸络合法制备不同A/B位金属的ABO_(3)钙钛矿型载氧体,通过研究A/B位金属变化对乙烷催化反应性能的影响,得到具有最佳反应活性的载氧体。运用XPS、O_(2)-TPD等方法对催化剂的结构进行表征,为探究其本征反应特性规律,通过动力学研究发现,在形成钙钛矿载氧体的不同A/B位金属中,BaCoO_(3)具有最佳的反应性能,其中乙烷转化率最高达到60%,乙烯选择性达到75%,乙烯收率最高为46%。BaCoO_(3)经过12次循环反应后,乙烯选择性基本保持不变,乙烷转化率降低约4%。通过表征分析发现,比表面积和孔径略微减小,表明载氧体具有优良的稳定性。

关键词：乙烯化学链式氧化钙钛矿载氧体半径及价态氧化脱氢

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左旋葡聚糖溶剂热转化为高值化学品的研究进展

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洁净煤技术 2024年第2期30卷 143-152页

作者：唐广川黄鑫秦辉余飞繁刘天龙魏富冉景煜重庆大学低品位能源利用技术及系统教育部重点实验室重庆400044 中国矿业大学江苏省碳资源精细化利用工程研究中心江苏徐州221116 中国矿业大学碳中和研究院江苏徐州221116

木质纤维素热解是一种高效生物质利用途径,其衍生产物左旋葡聚糖(LGA)是纤维素热解产物中最主要的初级产物,其产率可高达80%,将LGA高效转化为其他平台化学品可实现其高值化利用。首先综述了纤维素热解制备LGA的研究进展,对比反应器类型... 详细信息

木质纤维素热解是一种高效生物质利用途径,其衍生产物左旋葡聚糖(LGA)是纤维素热解产物中最主要的初级产物,其产率可高达80%,将LGA高效转化为其他平台化学品可实现其高值化利用。首先综述了纤维素热解制备LGA的研究进展,对比反应器类型和反应条件对LGA产率的影响,生物质预处理工艺将进一步提升工业化规模制备LGA。然后概述了LGA在不同条件下转化为左旋葡萄糖酮、葡萄糖和呋喃类化合物的最新研究进展。发现在LGA溶剂热催化转化为左旋葡萄糖酮的过程中,催化剂Bronsted酸性位点及原位移除反应生成的水分有助于提升左旋葡萄糖酮的产率,最优条件下左旋葡萄糖酮的最大产率可接近60%,开发合适的催化剂及溶剂体系有助于进一步提高左旋葡萄糖酮产率。通过酸水解作用,LGA转化为葡萄糖的产率及选择性均可达近100%,且催化剂能够长时间稳定运行,该方法提供了一个由纤维素间接生产葡萄糖的方法。最后,总结了催化剂理化特性及溶剂条件对LGA生成呋喃类和酸酯类化合物的影响规律,发现葡萄糖间接转化机制可促进LGA高效转化为此类化学品。

关键词：生物质溶剂热转化左旋葡聚糖左旋葡萄糖酮葡萄糖呋喃类化合物

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纳米液滴撞击润湿阵列碳纳米管的分子模拟

工程热物理学报 2024年第9期45卷 2678-2686页

作者：冯潇源冉景煜邵运璘黄鑫杨桐桑国华重庆大学能源与动力工程学院重庆400044

利用分子动力学模拟方法研究了水纳米液滴在不同阵列碳纳米管上的润湿特性,考察了不同结构与表面改性阵列碳纳米管、不同纳米液滴初始运动状态对润湿特性的影响。结果表明:手性参数n=30、m=0碳纳米管的抗水性能更强,顺排排列、间距为9 n... 详细信息

利用分子动力学模拟方法研究了水纳米液滴在不同阵列碳纳米管上的润湿特性,考察了不同结构与表面改性阵列碳纳米管、不同纳米液滴初始运动状态对润湿特性的影响。结果表明:手性参数n=30、m=0碳纳米管的抗水性能更强,顺排排列、间距为9 nm时阵列碳纳米管有利于保持液滴形态,可避免不规则润湿现象发生;在环境温度升高过程中,纳米液滴在表面的扩散行为由液滴的铺展逐渐转变为气体的扩散;纳米液滴We数为6.74时,无量纲润湿半径最小,润湿过程由表面张力主导转变为惯性力主导;纳米液滴运动角度的改变不影响液滴最终润湿半径,但在小角度会出现不规则润湿现象,造成纳米液滴的动能在摩擦与形变中损耗,对抗水性能有不利影响。

关键词：润湿性阵列碳纳米管纳米液滴分子动力学

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基于5E模型的创新实践课程教学设计与实施

高教学刊 2024年第29期10卷 23-26,31页

作者：杨仲卿朱晨萱冉景煜重庆大学能源与动力工程学院重庆400044

传统“教师讲授,学生聆听”的教学模式不利于激发学生自主创造性,无法有效提升学生的问题解决能力,因而不能较好地实现创新实践类课程的教学目标。对此,该文提出基于5E模型的课程设计,并将其运用于能源动力类本科专业节能减排创新实践... 详细信息

传统“教师讲授,学生聆听”的教学模式不利于激发学生自主创造性,无法有效提升学生的问题解决能力,因而不能较好地实现创新实践类课程的教学目标。对此,该文提出基于5E模型的课程设计,并将其运用于能源动力类本科专业节能减排创新实践课程。该教学设计下,学生需要开展小组合作学习,自主探索并提出问题,而后通过所学知识及相关信息的搜集、整合、运用使问题得到创造性的解决。实施过程中强调以学生为主体,教师在旁起辅助和引导作用。结果表明,该设计模型的实施能引导学生实现对知识的自主建构,有助于强化学生的自主学习能力及创新实践能力,并有效培育学生的科研精神,能够较好地实现创新实践课程的教学目标。

关键词：教学改革 5E模型节能减排创新实践创新创业新工科

A density functional theory study of methane activation on MgO supported Ni_(9)M_(1) cluster:role of M on C-H activation

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Frontiers of Chemical Science and Engineering 2022年第10期16卷 1485-1492页

作者： Juntian Niu Haiyu Liu Yan Jin Baoguo Fan Wenjie Qi jingyu ran College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Advanced Manufacturing Technology for Automobile Parts Ministry of EducationChongqing University of TechnologyChongqing 400050China Key Laboratory of Low-grade Energy Utilization Technologies and Systems Ministry of EducationChongqing UniversityChongqing 400044China

Methane activation is a pivotal step in the application of natural gas converting into high-value added chemicals via methane steam/dry reforming *** element was found to be the most widely used *** present work,methane activation on MgO supported Ni–M(M=Fe,Co,Cu,Pd,Pt)cluster was explored through detailed density functional theory calculations,compared to pure Ni ***_(4)adsorption on Cu promoted Ni cluster requires overcoming an energy of 0.07 eV,indicating that it is slightly endothermic and unfavored to occur,while the adsorption energies of other promoters M(M=Fe,Co,Pd and Pt)are all higher than that of pure Ni *** role of M on the first C–H bond cleavage of CH_(4)was *** elements of the same period in Ni cluster,such as Fe,Co and Cu,for C–H bond activation follows the trend of the decrease of metal atom *** a result,Ni–Fe shows the best ability for C–H bond *** addition,doping the elements of the same family,like Pd and Pt,for CH_(4)activation is according to the increase of metal atom ***,C–H bond activation demands a lower energy barrier on Ni–Pt *** illustrate the adsorptive dissociation behaviors of CH_(4)at different Ni–M clusters,the Mulliken atomic charge was *** general,the electron gain of CH_(4)binding at different Ni–M clusters follows the sequence of Ni–Cu(–0.02 e)

关键词： CH_(4) dissociation Ni-M C-H bond activation charge transfer

Hierarchical model updating for high-speed maglev vehicle/guideway coupled system based on multiobjective optimization

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 788-804页

作者： Dexiang Li jingyu Huang College of Civil Engineering Tongji UniversityShanghai 200092China National Maglev Transportation Engineering R&D Center Tongji UniversityShanghai 201804China

The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchical model updating method integrated with field ***,a high-speed maglev vehicle/guideway coupled model,taking into account the real effect of guideway material properties and elastic restraint of bearings,was developed by integrating the finite element method,multi-body dynamics,and electromagnetic levitation ***,simultaneous in-site measurements of the vehicle/guideway were conducted on a high-speed maglev test line to analyze the system response and structural modal *** the hierarchical updating,an Elman neural network with the optimal Latin hypercube sampling method was used to substitute the FE guideway model,thus improving the computational *** multi-objective particle swarm optimization algorithm with the gray relational projection method was applied to hierarchically update the parameters of the guideway layer and magnetic force layer based on the measured modal parameters and the electromagnet vibration,***,the updated coupled model was compared with the field measurements,and the results demonstrated the model’s accuracy in simulating the actual dynamic response,validating the effectiveness of the updating method.

关键词： high-speed maglev vehicle/guideway coupled model field measurement model updating neural network multi-objective optimization

改性LaCoO_(3)用于烟气脱Hg^(0)性能研究

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工程热物理学报 2023年第1期44卷 137-143页

作者：何智冉景煜黄鑫何威冉子俊重庆大学低品位能源利用技术及系统教育部重点实验室重庆400044 重庆大学能源与动力工程学院重庆400044

采用实验方法研究了LaCoO_(3)、La_((1-x))CexCoO_(3)(x=0~0.2)、LaCo_((1-y))MnyO_(3)(y=0~0.15)钙钛矿用于燃煤烟气中元素汞(Hg^(0))脱除,深入探讨了烟气主要成分(O_(2)、SO_(2)、H_(2)O)对Hg0脱除效率的影响。结果表明,La_(0.875)Ce_(0.125)CoO_(3)比LaCoO_(3)具有更高的氧吸附性能,在150℃条件下能实现99.2%的Hg0脱除效率。气态O_(2)是该反应中重要的氧化剂,H_(2)O的负面效果被SO_(2)的加入而抵消。La_(0.875)Ce_(0.125)CoO_(3)在600℃下热再生并循环使用5次后仍然有75.04%的脱汞效率,La_(0.875)Ce_(0.125)CoO_(3)在低温下脱汞性能优异。

关键词： Hg^(0)脱除钙钛矿氧化物燃煤烟气

A Planning Method for Operational Test of UAV Swarm Based on Mission Reliability

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1889-1918页

作者： jingyu Wang Ping Jiang Jianjun Qi College of Systems Engineering National University of Defense TechnologyChangsha410073China Beijing Special Engineering Design Institution Beijing100028China

The unmanned aerial vehicle(UAV)swarm plays an increasingly important role in the modern battlefield,and the UAV swarm operational test is a vital means to validate the combat effectiveness of the UAV *** to the high cost and long duration of operational tests,it is essential to plan the test in *** solve the problem of planning UAV swarm operational test,this study considers the multi-stage feature of a UAV swarm mission,composed of launch,flight and combat stages,and proposes a method to find test plans that can maximize mission ***,a multi-stage mission reliability model for a UAV swarm is proposed to ensure successful implementation of the mission.A multi-objective integer optimization method that considers both mission reliability and cost is then formulated to obtain the optimal test *** study first constructs a mission reliability model for the UAV swarm in the combat ***,the launch stage and flight stage are integrated to develop a complete PMS(Phased Mission Systems)reliability ***,the Binary Decision Diagrams(BDD)and Multi Objective Quantum Particle Swarm Optimization(MOQPSO)methods are proposed to solve the *** optimal plans considering both reliability and cost are *** proposed model supports the planning of UAV swarm operational tests and represents a meaningful exploration of UAV swarm test planning.

关键词： UAV swarm PMS MOQPSO BDD mission reliability operational test planning