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新型核壳AuTi@PtNi纳米催化剂:增强氧还原催化活性及稳定性（英文）

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Chinese Journal of Catalysis 2024年第1期56卷 81-87页

作者： Giday Fisseha 于亚楠鲁少杰胡一平周雨岳秦电子科技大学基础与前沿研究院清华四川能源互联网研究院

质子交换膜燃料电池（PEMFCs）将化学燃料转化为电能,具有能量转换效率高、清洁、零排放等特点,被认为是未来重要的能源利用装置.与阳极发生的氢氧化反应相比,阴极发生的氧还原反应（ORR）是动力学缓慢的过程,严重阻碍了燃料电池的广泛... 详细信息

质子交换膜燃料电池（PEMFCs）将化学燃料转化为电能,具有能量转换效率高、清洁、零排放等特点,被认为是未来重要的能源利用装置.与阳极发生的氢氧化反应相比,阴极发生的氧还原反应（ORR）是动力学缓慢的过程,严重阻碍了燃料电池的广泛应用,因此迫切需要开发高活性的电催化剂来降低其电化学过电位,提高反应动力学.铂基纳米晶是氧还原反应有效的电催化剂,但存在成本高、储量少且耐用性差等问题.将铂（Pt）与过渡金属（Fe, Co, Ni等）合金化可以提升催化活性,且最外层有序的Pt原子层可以有效地避免过渡金属的腐蚀溶解,同时,利用金（Au）与Pt基合金形成核壳结构可以有效地降低催化剂成本,同时增强稳定性.然而,在以Au作为核时,很难通过退火处理获得富含Pt层的核壳催化剂.本文利用钛（Ti）原子与Au原子合金化后的协同作用,成功地制备了核壳AuTi@PtNi氧还原催化剂.由于Ti与Au的强相互作用,使得该催化剂即使经高温退火处理,依旧可以使Au保持在内部,同时可以获得富Pt壳层.利用配备有电子能量损失谱的透射电子显微镜及X射线电子能谱对催化剂进行表征,结果表明, Ti的引入可大大提升催化剂的热稳定性.由于具有核壳结构及富Pt的PtNi壳层,退火后的Au Ti@PtNi-400催化剂在0.9 V（RHE）时的质量比活性(5.26 AmgPt-1)和面积比活性(2.72 mAcm-2)分别是商业化Pt/C催化剂的19.26倍和9.84倍.另外, AuTi@PtNi-400催化剂在20000圈循环测试后质量活性衰减不到10%,稳定性好于商业化Pt/C催化剂和未经过退火的AuTi@PtNi催化剂.进一步对AuTi@PtNi-400进行电催化测试,结果表明,在功率密度达到0.61 Wcm-2的同时可产生1.31 Acm-2的电流密度,该结果优于商业化Pt(1.05 Acm-2和0.34Wcm-2)以及Ti-Au@PtNi/C (1.25 Acm-2和0.62 Wcm-2),峰值功率密度高达0.80 Wcm-2,这表明所制备的Ti-Au@PtNi/C-400催化剂不仅在三电极体系中具有较好的性能,在电堆测试中也展现出高性能,可以较大地满足和促进燃料电池的发展和应用.综上所述,对于燃料电池阴极催化剂,可结合形貌工程及协调作用,制备出低成本高性能的ORR催化剂,为燃料电池的进一步应用提供新思路.

关键词：钛掺杂富铂层热处理氧化还原反应核壳结构

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一种新型卧倒式坞门用铰点与止水装置设计

船舶标准化工程师 2024年第1期57卷 50-55页

作者：徐舒翎陆少杰上海海事大学工程训练中心上海201306

为有效提高坞门开闭效率,延长其使用寿命,对基于传统卧倒式坞门的铰点与止水装置进行优化设计,并在此基础上设计一种新型的卧倒式坞门用铰点与止水装置。研究表明:新型的卧倒式坞门铰点及止水装置设计安装可靠、使用方便、开闭及拆装简... 详细信息

为有效提高坞门开闭效率,延长其使用寿命,对基于传统卧倒式坞门的铰点与止水装置进行优化设计,并在此基础上设计一种新型的卧倒式坞门用铰点与止水装置。研究表明:新型的卧倒式坞门铰点及止水装置设计安装可靠、使用方便、开闭及拆装简便,止水效果显著。研究成果可为卧倒式坞门设计提供一定参考。

关键词：卧倒式坞门开闭效率铰点止水装置

Failure analysis and control measures of deep roadway with composite roof:a case study

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International Journal of Coal Science & Technology 2022年第1期9卷 120-137页

作者： Yongliang Li Renshu Yang Shizheng Fang Hai Lin shaojie lu Ye Zhu Maosheng Wang School of Energy and Mining Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China

There is great variation in the lithology and lamination thickness of composite roof in coal-measure strata;thus,the roof is prone to delamination and falling,and it is difficult to control the surrounding rock when developing roadway in such rock *** deep mining,the stress environment of surrounding rock is complex,and the mechanical response of the rock mass is different from that of the shallow rock *** composite-roof roadway excavated in deep rock mass,the key to safe and efficient production of the mine is ensuring the stability of the *** present paper obtains typical failure characteristics and deformation and failure mechanisms of composite-roof roadway with a buried depth of 650 m at Zhaozhuang Coal Mine(Shanxi Province,China).On the basis of determining a reasonable cross-section shape of the roadway and according to the failure characteristics of the composite roof in different regions,the roof is divided into an unstable layer,metastable layer,and stable *** controlled unstable layer and metastable layer are regarded as a small structure while the stable layer is regarded as a large structure.A superimposed coupling support technology of large and small structures with a multi-level prestressed bearing arch formed by strong rebar bolts and highly prestressed cable bolts is put *** support technology provides good application results in the *** study thus provides theoretical support and technical guidance for ground control under similar geological conditions.

关键词： Deep mining Composite roof Failure mechanism Ground control

An in-situ polymerized interphase engineering for high-voltage allsolid- state lithium-metal batteries

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Nano Research 2024年第4期17卷 2687-2692页

作者： lu Nie shaojie Chen Mengtian Zhang Tianyi Gao Yuyao Zhang Ran Wei Yining Zhang Wei Liu School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Tsinghua-Berkeley Shenzhen Institute&Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China

All-solid-state lithium batteries(ASSLBs)have attracted great interest due to their promising energy density and strong ***,the interface issues,including large interfacial resistance between electrode and electrolyte and low electrochemical stability of solid-state electrolytes against high-voltage cathodes,have restricted the development of high-voltage ***,we report an ASSLB with stable cycling by adopting a conformal polymer interlayer in-situ formed at the Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)–cathode *** polymer can perfectlyﬁll the voids and create a stable interface contact between LLZTO and *** addition,the electric field across the polymer interlayer is reduced compared with pure solid polymer electrolyte(SPE),which facilitates the electrochemical stability with high-voltage *** all-solid-state Li|LLZTO-SPE|LiFe_(0.4)Mn_(0.6)PO_(4)(LMFP)cells achieve a low interface impedance,high specific capacity,and excellent cycling *** work presents an effective and practical strategy to rationally design the electrode–electrolyte interface for the application of high-voltage ASSLBs.

关键词： all-solid-state lithium batteries interface contact electric field electrochemical stability

Screwdriver-like Pd-Ag heterostructures formed via selective deposition of Ag on Pd nanowires as efficient photocatalysts for solvent-free aerobic oxidation of toluene

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Nano Research 2020年第3期13卷 646-652页

作者： Caihong He Lingli Yu Na lu Wenjing Wang Wei Chen shaojie lu Yun Yang Dekun Ma Shaoming Huang Key Laboratory of Carbon Materials of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou University Wenzhou 325035China School of Materials and Energy Guangdong University cf TechnologyGuangzhou 510006China

Heterostructured bimetal nanocrystals with a component having localized surface plasmon resonance(LSPR)property are promising photocatalysts for a series of *** this work,kinetic products of Pd-Ag with a screwdriver-like heterostructure have been successfully fabricated via the selective epitaxial growth of Ag on Pd nanowires(NWs).It was confirmed that the deposition rate(Vdeposition)of Ag is much more sensitive to the temperature,compared to the surface diffusion rate(Vdiffusion)which can be effectively reduced by the binding of poly(vinylpyrrolidone)(PVP)*** the magnitude of Vdeposition/Vdiffusion has been well tailored for the formation of a kinetic growth *** interactions between the components of the as-prepared Pd-Ag heterostructures resulted in intensified LSPR *** a result,they gained better photocatalytic performance toward solvent free aerobic oxidation of toluene than Pd NWs,Ag NWs and the mixture of ***,the Pd-Ag heterostructured nanocrystals exhibited excellent catalytic stability for *** work not only presents an idea for realizing kinetic growth but also supports that LSPR effect is a good tool for improving the photocatalytic activity.

关键词： heterostructure selective growth kinetics aerobic oxidation reaction

Design and experiment of vertical pneumatic fertilization system with spiral Geneva mechanism

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International Journal of Agricultural and Biological Engineering 2021年第4期14卷 135-144页

作者： Haibo Chen Jingfu Zheng shaojie lu Shan Zeng Silong Wei Experimental Basis and Practical Training Center South China Agricultural UniversityGuangzhou 510642China College of Engineering South China Agricultural UniversityGuangzhou 510642China

In the traditional fertilization method,a large amount of fertilizer is applied,which causes congestion *** is not conducive to the sustainable development of *** this work,a vertical pneumatic fertilization system with a spiral Geneva mechanism was designed according to the operational requirements of variable-rate and smooth *** uniformity in discharging fertilizer with different spiral angles was simulated and analyzed by extended discrete element method(EDEM)based simulation software,from where the spiral angle of the fertilizer discharge wheel was determined to be 45°.The fertilization system includes a fertilizer apparatus with a spiral Geneva mechanism,whose optimal performance parameters were obtained from the bench *** accuracy and uniformity of the fertilizer application system were taken as the evaluation *** linear relationships of the discharged amount of fertilizer with the rotational speed and the opening of the fertilizer discharging wheel were verified by both static blowing fertilization and field *** static blowing experimental results show that the discharged amount of fertilizer has a high linear correlation and accuracy with both the opening and rotational speed,and the highest correlation occurs with the rotational *** rotational speed and opening have significant effects on the discharged amount of fertilizer and the average coefficient of *** effect of the rotational speed was the most *** to the model obtained by multiple regression fittings,the optimal parameters were determined when the average coefficient of variation was small,the rotational speed was 15.9 r/min and the opening was 34.4 ***,the purpose of precise fertilization can be achieved by adjusting the opening or rotational speed in a way to get the exact amount of fertilizer discharged as required by the corresponding *** field experiment showed that the variation co

关键词： precision fertilization fertilizer apparatus variable rate technology spiral Geneva mechanism simulation analysis performance experiment

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重塑国家发展治理:分税制改革三十年评述

经济理论与经济管理 2024年第5期44卷 25-53页

作者：周绍杰杨璐清华大学公共管理学院 100084 清华大学国情研究院

本文以1994年分税制改革为起点,系统评述了中国现代财政体制的演进历程和影响。首先回顾了分税制改革的背景和主要内容,接着探讨了分税制改革后中国财政体制改革的持续推进,包括法治建设、改革思路、重要举措以及未来改革的重点和难点... 详细信息

本文以1994年分税制改革为起点,系统评述了中国现代财政体制的演进历程和影响。首先回顾了分税制改革的背景和主要内容,接着探讨了分税制改革后中国财政体制改革的持续推进,包括法治建设、改革思路、重要举措以及未来改革的重点和难点。其次分析了分税制改革后我国财政体制的运行情况,包括总体财力、中央与地方财政收入分配、地方财力构成以及预算支出等公共资金的汲取与配置问题。最后论证了财政体制建设与国家发展治理的关系,包括完善市场经济体制、宏观经济调控和提升国家发展治理能力等方面。通过对历年数据的分析和图表呈现,本文得出如下结论:第一,分税制改革是中国财政体制历史上的一次深刻变革,是重新界定中央与地方财政关系的一个起点,此后财政体制的持续改革不断推进了财政治理体系与治理能力现代化。第二,分税制改革提升了国家以及中央的财政汲取能力,为有效推进国家发展治理提供了财政基础。第三,分税制改革后,随着财政体制的不断完善,财政对于国家发展治理发挥了积极作用。本文全面评估了分税制改革对中国国家发展治理的重要影响和未来发展的挑战与机遇。

关键词：分税制财政体制国家发展治理

成庄矿大采高工作面柔模混凝土沿空留巷技术研究

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煤炭技术 2023年第10期42卷 16-21页

作者：张晋斌路绍杰中国矿业大学(北京)能源与矿业学院北京100083 晋能控股煤业集团晋城煤炭事业部成庄矿山西晋城048000

为了解决大采高工作面沿空留巷变形控制难题,以成庄矿大采高工作面沿空留巷为工程背景,采用现场调研、理论分析和数值模拟等方法,分析了大采高工作面沿空留巷覆岩结构特征,获得了影响大采高工作面沿空留巷变形的关键因素。基于大采高工... 详细信息

为了解决大采高工作面沿空留巷变形控制难题,以成庄矿大采高工作面沿空留巷为工程背景,采用现场调研、理论分析和数值模拟等方法,分析了大采高工作面沿空留巷覆岩结构特征,获得了影响大采高工作面沿空留巷变形的关键因素。基于大采高工作面沿空留巷围岩控制难点,提出了以“柔模混凝土巷旁支护和预裂切顶卸压”为核心的大采高工作面沿空留巷围岩控制技术。重点分析了未切顶和切顶条件下大采高工作面沿空留巷围岩应力环境与变形特点,阐明了沿空留巷切顶卸压控制原理,确定了沿空留巷围岩支护参数。现场监测表明,大采高工作面沿空留巷采用新技术后,围岩大变形得到有效控制,留巷效果好。

关键词：大采高沿空留巷柔模混凝土切顶卸压

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食用化学品的发展前景

现代化工 2000年第9期20卷 1-5页

作者：吕绍杰中国食品日用化学品工业协会北京100011

食用化学品是重要的精细化工产品 ,市场呈稳步增长趋势。我国食用化学品生产已初具规模 ,可基本满足食品工业的需要 ,还有少量出口。本文介绍了我国主要食用化学品的现状及发展前景。

关键词：食用化学品品种市场发展前景