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Nano Research 2024年第9期17卷 8552-8559页

作者： donghao zhang Lianxi Si Qianqian Ren Xintong Yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

通过诱导载流子的V坑传输提升GaN基绿光LED的空穴注入效率

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发光学报 2024年第5期45卷 800-808页

作者：张东皓杨东锴徐畅刘信佑包立君厦门大学电子科学与技术学院电子科学系福建厦门361100 厦门三安光电有限公司福建厦门361100

为了提升GaN基多量子阱LED的空穴注入效率,设计了具有不同最后势垒层结构的GaN基多量子阱外延结构,并将其制备为绿光mini-LED发光芯片,利用低温电致发光光谱、电流电压特性测试对其载流子传输机制进行了研究。结果表明,在采用AlGaN或GaN... 详细信息

为了提升GaN基多量子阱LED的空穴注入效率,设计了具有不同最后势垒层结构的GaN基多量子阱外延结构,并将其制备为绿光mini-LED发光芯片,利用低温电致发光光谱、电流电压特性测试对其载流子传输机制进行了研究。结果表明,在采用AlGaN或GaN/AlN最后势垒层的样品中,有更多载流子可以传输到深层量子阱,空穴注入效率获得提升。本文对这一现象中的载流子运输机制以及V坑缺陷在其中所起的作用进行了研究,发现这种提升主要来自空穴V坑注入比例的增大。实验还发现,过大的V坑注入比例也会造成非辐射复合率上升,从而抑制了AlGaN最后势垒层样品的电光转换效率。

关键词：发光二极管最后势垒层空穴注入 InGaN/GaN多量子阱 V坑

基于数据支撑的高校理科学报“深体检”方法研究——以《南开大学学报(自然科学版)》为例

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天津科技 2024年第1期51卷 55-57,61页

作者：陈玮彭艺张栋豪南开大学学报编辑部天津300071

针对学界关注的提高高校学报的学术质量问题,提出了对高校学报进行“深体检”的方法,并以《南开大学学报(自然科学版)》为例,从作者分布、服务质量及报道方向这3个方面开展深度“体检”,从中归纳出高校学报的改进措施。该方法有一定的... 详细信息

针对学界关注的提高高校学报的学术质量问题,提出了对高校学报进行“深体检”的方法,并以《南开大学学报(自然科学版)》为例,从作者分布、服务质量及报道方向这3个方面开展深度“体检”,从中归纳出高校学报的改进措施。该方法有一定的普适性,适用于国内大部分高校理科学报。

关键词：高校学报期刊学术质量作者分布服务质量报道方向

基于跨孔雷达的水工防渗墙无损检测实验系统设计

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实验技术与管理 2024年第5期41卷 9-14页

作者：唐玉康飞宿晓辉张建涛张东昊姚遥大连理工大学建设工程学院辽宁大连116024

水利学科前沿实验是“新工科”人才培养模式下实验教学的重要环节。为丰富前沿实验内容,将科研与教学紧密结合,设计了跨孔雷达检测水工防渗墙隐蔽病害的可视化实验系统。该系统由可视化水箱、可视化模型箱和跨孔雷达系统三部分组成。可... 详细信息

水利学科前沿实验是“新工科”人才培养模式下实验教学的重要环节。为丰富前沿实验内容,将科研与教学紧密结合,设计了跨孔雷达检测水工防渗墙隐蔽病害的可视化实验系统。该系统由可视化水箱、可视化模型箱和跨孔雷达系统三部分组成。可视化水箱尺寸为1.2 m×1.0 m×1.5 m;可视化模型箱尺寸为0.6 m×0.2 m×1.0 m;跨孔雷达系统由网络分析仪和收发天线采集数据,由控制主机存储和显示数据。实验教学表明,该系统能够利用跨孔雷达有效检测出水工防渗墙内部隐蔽病害,具有较强的创新性和前沿性,有助于激发学生的创新思维,提高科研能力,达到以研促教、教研相长的目的。

关键词：实验教学水工防渗墙跨孔雷达无损检测隐蔽病害

Shape-dependence in seeded-growth of Pd-Cu solid solution from Pd nanostructure towards methanol oxidation electrocatalyst

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Nano Research 2023年第7期16卷 9116-9124页

作者： Lianxi Si Hui Li Yu zhang donghao zhang Xiaowei An Mengmeng Yao Yuanyuan Shao Jesse Zhu Shi Hu School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China College of Environmental Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Ultrathin Pd nanosheets(NSs)have great advantages in catalysis due to their large specific surface area and high percentage of under-coordinated ***,the electrochemical performance still can be improved via composition-controllable growth of their solid ***,seeded alloying strategy was proposed to synthesize Pd-Cu solid solution from Pd NSs and Pd-Cu nanostructures with tunable molar ratios obtained by changing the amount of Cu *** compared to the pristine Pd NSs,the Pd-Cu solid solution shows significantly enhanced methanol oxidation reaction(MOR)performance over those of Pd NSs and homemade Pd/C as the incorporation of Cu weakens the adsorption of CO intermediate on Pd in the MOR *** choice of template is pivotal to the growth,as a shape-dependent behavior could be identified in the alloying of Cu with Pd nanosheets enclosed by{111}and{100}facets,Pd nanocubes enclosed by{100}facet,and Pd nano-tetrahedrons enclosed by{111}*** Pd-Cu solid solution with tunable composition can only be obtained from Pd NSs and the shape-dependent alloying process is mainly determined by the diffusion barrier and the minimum diffusion depth of the different facets.

关键词： Pd-Cu alloy nanosheets tunable composition methanol oxidation reaction optimized electronic structure weakened COadsorption

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吉林省洮南金蟾一带控矿因素及找矿方向研究

吉林地质 2024年第2期43卷 45-49页

作者：张国峰张东浩都军朱航王鹏飞吉林省第三地质调查所吉林四平136000

笔者通过近年来在吉林省洮南金蟾一带的地质勘查工作,大致查明了本区的地层、构造、岩浆岩分布特征,分别圈定综合异常10处、圈定5条北东向视极化率异常带、高磁异常8处、断裂构造5条,并且新发现矿(化)体16条。结合成果实际材料,综合研... 详细信息

笔者通过近年来在吉林省洮南金蟾一带的地质勘查工作,大致查明了本区的地层、构造、岩浆岩分布特征,分别圈定综合异常10处、圈定5条北东向视极化率异常带、高磁异常8处、断裂构造5条,并且新发现矿(化)体16条。结合成果实际材料,综合研究发现本区的矿(化)体与物化探异常形态相吻合,物化探异常形态与本区北东向断裂构造、北西向次级构造方向大致吻合,进一步验证了该地区找矿远景及潜力。通过成果实际材料研究比对,初步认为矿(化)体的存在与区域内发育的火山岩、断裂构造有着密切的因果关系。

关键词：铜及多金属矿控矿因素找矿方向研究吉林省洮南金蟾一带

Electrochemical filtration for drinking water purification:A review on membrane materials,mechanisms and roles

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Journal of Environmental Sciences 2024年第7期141卷 102-128页

作者： Yuying Qi donghao Li Shixuan zhang Fengxiang Li Tao Hua College of Environmental Science and Engineering Nankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationTianjin 300350China Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation Tianjin 300350China

Electrochemical filtration can not only enrich low concentrations of pollutants but also produce reactive oxygen species to interact with toxic pollutants with the assistance of a power supply,making it an effective strategy for drinking water *** addition,the application of electrochemical filtration facilitates the reduction of pretreatment procedures and the use of chemicals,which has outstanding potential for maximizing process simplicity and reducing operating costs,enabling the production of safe drinking water in smaller *** recent years,the research on electrochemical filtration has gradually increased,but there has been a lack of attention on its application in the removal of low concentrations of pollutants from low conductivity *** this review,membrane substrates and electrocatalysts used to improve the performance of electrochemical membranes are briefly ***,the application prospects of emerging single-atom catalysts in electrochemical filtration are also ***,several electrochemical advanced oxidation processes coupled with membrane filtration are described,and the related working mechanisms and their advantages and shortcomings used in drinking water purification are ***,the roles of electrochemical filtration in drinking water purification are presented,and the main problems and future perspectives of electrochemical filtration in the removal of low concentration pollutants are discussed.

关键词： Electrochemical filtration Drinking water Conductive membrane Low concentration Electrocatalyst

Luminescence and magnetic properties of bifunctional nanoparticles composited by nitrogen-doped graphene quantum dots and gadolinium

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Journal of Rare Earths 2024年第4期42卷 716-723页

作者： Wanli zhang Hao Zhou Meigui Ou donghao Sun Chunlin Yang College of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang550025 China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang550003China

In this paper,nitrogen-doped graphene quantum dots(N-GQDs)were combined with gadolinium ions(Gd^(3+))by a surface modification to obtain magneto-optical dual-functional N-GQDs/Gd^(3+)*** morphology of obtained composite was characterized by field emission scanning electron microscopy and transmission electron *** and magnetic properties were measured by a fluorescence spectrophotometer and a vibrating sample magnetometer,*** indicate that well-dispersed spherical N-GQDs/Gd^(3+)nanoparticles have an average diameter of 7 nm.N-doping significantly increases the luminesce nce of particles with an optimal luminescence intensity at 20℃and pH=9.X-ray photoelectron spectroscopy results indicate that the N-doping introduces pyrrolic N as an electron donor,enhancing fluorescence by increasing the surface electron cloud density of *** addition,density functional theory calculation results reveal that N-doping reduces the band gap of NGQDs/Gd^(3+),enabling electronic transitions to higher energy levels and generating more activation sites,thereby enhancing *** to N-GQDs/Gd^(3+)prepared at 20℃,the saturated magnetization of particles prepared at 40℃is 0.85 emu/g,indicating a better magnetic *** above results suggest that bifunctional nanomaterials N-GQDs/Gd^(3+)with excellent optical properties and magnetism can be better used for fluorescence and magnetic resonance imaging.

关键词： Nitrogen-doped graphenequantum dots Gadolinium Luminescence Magnetism Rare earths

Ignition and Lean Blowout Characteristics of a Reverse-Flow Combustor for an Ultra-Compact Gas Turbine Engine

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Journal of Thermal Science 2024年第5期33卷 1897-1906页

作者： JIN Yi HUANG Yakun YAO Kanghong zhang Kai WANG Yunbiao WANG donghao College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094China Low-carbon Aerospace Power Engineering Research Center of Ministry of Education Nanjing 210016China

The flame stability limit and propagation characteristics of a reverse-flow combustor without any flame-stabilized device were experimentally investigated under room temperature and *** results indicate that it is feasible to stabilize the flame in the recirculation zones constructed by the impact jet flow from the primary holes and dilution *** flame projected area is mainly distributed in the recirculation zone upstream of the primary holes,whose presence and absence mark the ignition and *** the ignition process,the growth rate and value of the flame projected area first increase and then decrease with the inlet velocity increasing from 9.4 m/s to 42.1 m/s.A rapid reduction followed by a slow reduction of ignition and lean blowout equivalence ratios is achieved by the increased inlet *** the non-reacting fluid structure in three sections was measured,and detailed velocity profiles were analyzed to improve the understanding of the flame stabilization *** results are conducive to the design of an ultra-compact combustor.

关键词： ultra-compact combustor gas turbine reverse-flow combustor ignition lean blowout

Mitigation strategies for soil acidification based on optimal nitrogen management

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 229-242页

作者： Pengshun WANG donghao XU Prakash LAKSHMANAN Yan DENG Qichao ZHU Fusuo zhang College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China National Academy of Agriculture Green Development China Agricultural UniversityBeijing 100193China Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400716China Sugarcane Research Institute Guangxi Academy of Agricultural SciencesNanning 530007China Queensland Alliance for Agriculture and Food Innovation University of QueenslandSt Lucia 4067BrisbaneQueenslandAustralia

Soil acidification is a serious constraint to food production *** review explores its primary causes,with a focus on the role of nitrogen fertilizer,and suggests mitigation strategies based on optimal N *** acidification is determined by the leaching of weak acid mainly caused by climate and soil conditions,whereas the use of ammonium-based fertilizers,nitrate leaching and removal of base cations(BCs)by crop harvesting mostly accounts for anthropogenic *** addition,low soil acid buffering capacity,mainly determined by soil parent materials and soil organic matter content,also accelerates *** study proposes targeted mitigation strategies for different stages of soil acidification,which include monitoring soil carbonate content and p H of soils with p H>6.5(e.g.,calcareous soil),use of alkaline amendments for strongly acidic soils(p H<5.5)with aluminum toxicity risk to p H between 5.5 and 6.5,and decreasing acidification rates and supplementing BCs to maintain this optimal p H range,especially for soils with low acid buffering *** mitigation involves optimizing the rate and form of N fertilizers used,regulating N transformation processes,and establishing an integrated soil–crop management system that balances acid production and soil buffering capacity.

关键词： Soil acidification nutrient management nitrogen soil buffering capacity