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Communications in Theoretical Physics 2020年第11期72卷 30-36页

作者： Dong Wang Yi-Tian Gao cui-cui ding Cai-Yin Zhang Ministry-of-Education Key Laboratory of Fluid Mechanics and National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and AstronauticsBeijing 100191China

Under investigation in this paper is a generalized(3+1)-dimensional Kadomtsev-Petviashvili equation in fluid dynamics and plasma *** and one-periodic-wave solutions are obtained via the Hirota bilinear method and Hirota-Riemann *** and velocity of the one soliton are *** are presented to discuss the solitons and one-periodic waves:the coefficients in the equation can determine the velocity components of the one soliton,but cannot alter the soliton magnitude;the interaction between the two solitons is elastic;the coefficients in the equation can influence the periods and velocities of the periodic *** between the one-soliton solution and one-periodic wave solution is investigated.

关键词： fluid dynamics plasma physics generalized(3+1)-dimensional Kadomtsev-Petviashvili equation solitons periodic waves

Review of Market Power Assessment and Mitigation in Reshaping of Power Systems

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1067-1084页

作者： Nan Shang Yi ding Wenqi cui Energy Development Research Institute.China Southern Power Grid GuangzhouChina College of Electrical Engineering Zhejiang UniversityHangzhouChina Department of Electrical and Computer Engineering University of WashingtonSeattleUSA

The deregulation of the power industry requires avoiding market power abuse to maintain the market competitiveness. To this end, a sequence of assessment measurements or mitigation mechanisms is required. Meanwhile, the increasing renewable energy resources(RESs) and flexible demand response resources(DRSs) are changing the behaviors of market participants and creating new cases of market power *** new circumstances bring the new evaluation and control methods of market power to the forefront. This paper provides a comprehensive review of market power in the reshaping of power systems due to the increasing RES and the development of DRS. The market power at the supply side, demand side,and in the multi-energy system is categorized and reviewed. In addition, the applications of market power supervision measures in the US, the Nordics, UK, and China are ***, the unsolved issues, possible key technologies,and potential research topics on market power are discussed.

关键词： Market power renewable energy source(RES) flexible demand response source(DRS) assessment mitigation

Numerical simulation of airflow distribution in mine tunnels

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International Journal of Mining Science and Technology 2017年第4期27卷 663-667页

作者： ding cui He Xueqiu Nie Baisheng Department of Safety Engineering China University of Labor Relations School of Civil and Environment Engineering University of Science and Technology Beijing School of Resource & Safety Engineering China University of Mining & Technology

Based on 3D modelling of typical tunnels in mines, the airflow distribution in a three-center arch-section tunnel is investigated and the influence of air velocity and cross section on airflow distribution in tunnels is studied. The average velocity points were analyzed quantitatively. The results show that the airflow pattern is similar for the three-center arch section under different ventilation velocities and cross sectional areas. The shape of the tunnel cross section and wall are the critical factors influencing the airflow pattern. The average velocity points are mainly close to the tunnel wall. Characteristic equations are developed to describe the average velocity distribution, and provide a theoretical basis for accurately measuring the average velocity in mine tunnels.

关键词： Mine tunnel Turbulence Airflow distribution Three-center arch Average velocity

Analytical model for predicting time-dependent lateral deformation of geosynthetics-reinforced soil walls with modular block facing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 711-725页

作者： Luqiang ding Chengzhi Xiao Feilong cui School of Civil and Transportation Engineering Hebei University of TechnologyTianjin300401China

To date,few models are available in the literature to consider the creep behavior of geosynthetics when predicting the lateral deformation(d)of geosynthetics-reinforced soil(GRS)retaining *** this study,a general hyperbolic creep model was first introduced to describe the long-term deformation of geosynthetics,which is a function of elapsed time and two empirical parameters a and *** conventional creep tests with three different tensile loads(Pr)were conducted on two uniaxial geogrids to determine their creep behavior,as well as the a-Pr and b-Pr *** test results show that increasing Pr accelerates the development of creep deformation for both ***,a and b respectively show exponential and negatively linear relationships with Pr,which were confirmed by abundant experimental data available in other *** on the above creep model and relationships,an accurate and reliable analytical model was then proposed for predicting the time-dependent d of GRS walls with modular block facing,which was further validated using a relevant numerical investigation from the previous *** evaluation and comparison of the proposed model with six available prediction models were *** a parametric study was carried out to evaluate the effects of wall height,vertical spacing of geogrids,unit weight and internal friction angle of backfills,and factor of safety against pullout on d at the end of construction and 5 years *** findings show that the creep effect not only promotes d but also raises the elevation of the maximum d along the wall ***,the limitations and application prospects of the proposed model were discussed and analyzed.

关键词： Geosynthetics Creep behavior Geosynthetics-reinforced soil(GRS)walls Lateral deformation Analytical model

Continuous high-temperature rapid nanomanufacturing of electrocatalysts

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Nano Research 2025年第1期18卷 225-235页

作者： Xiaoyang Wang Ziyi Luo Baihua cui Ziqi Fu Yanchang Liu Weidi Liu Jia ding Jianrong Zeng Yanan ChenWenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaBrisbane 4072Australia Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Encapsulating metal nanoparticles in carbon shells(Metal@C)to enhance catalytic activity and stability has been certified ***,most existing methods for preparing Metal@C are complex,time-consuming,and lack of *** this study,a novel method that couples the high-temperature shock(HTS)with ultrasonic spray pyrolysis is reported,which can realize facile and scalable production of various Metal@C through the pyrolysis of glucose and metal chloride *** proposed HTS ultrasonic spray pyrolysis offers several advantages,including compact size,short reaction time(~120 ms),and uniform *** the Ni@C-40 nanocomposite as an example,the ultrasmall Ni nanoparticles(~10 nm)with thin carbon protective shells(~2 nm)are uniformly dispersed in the carbon matrix and applied for oxygen evolution reaction(OER)in alkaline *** Ni@C-40 optimized by tuning the thickness of carbon shell exhibits significantly enhanced OER activity with low overpotential of 242 mV at 10 mA·cm^(-2) and stability,which is attributed to the optimized interactions between Ni nanoparticles and carbon *** method also shows promise for continuous pyrolysis synthesis of various extreme materials at ultra-high temperatures using alternative electric heating materials.

关键词： ultrasonic spray pyrolysis high-temperature shock carbon shell oxygen evolution reaction Metal@C nanocomposite

Chlorine-free emission disposal of spent acid etchant in a three-compartment ceramic membrane reactor

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Chinese Journal of Chemical Engineering 2020年第1期28卷 271-278页

作者： Fanglu Yuan Lele cui Peipei ding Wenheng Jing State Key Laboratory of Materials-Oriented Chemical Engineering National Engineering Research Center for Special Separation MembraneCollege of Chemical EngineeringNanjing Tech UniversityNanjing 211800China

Electrochemical technologies for the on-site treatment of spent acid etchant have received great attention due their ease of operation and economic benefits. On the other hand, a large amount of Cl2 is generated during the electrolysis process, which leads to potential environmental risks. In the present work, a novel threecompartment ceramic membrane flow reactor, including a cathode chamber, an anode chamber, and a gas absorption chamber was developed. The three chambers were divided by an Al2O3 ceramic membrane and a breathable hydrophobic anode diffusion electrode(ADE). The Cl2 evolution onset potential of the ADE was increased to 1.19 V from 1.05 V of the graphite felt, effectively inhibiting the chlorine evolution reaction(CER).The anode-generated Cl2 diffused into the gas absorption chamber through the ADE and was eventually consumed by the H2O2 adsorbent. Cu could be recovered without emitting chlorine due to the special structure of reactor. The current efficiency of copper precipitation and cathode reduction from Cu2+to Cu+reached 97.7%at a working current of 150 m A. These results indicated that the novel membrane reactor had high potential for application in the copper recovery industry.

关键词： Spent acid etchant Chlorine evolution reaction Anode diffusion electrode Three-compartment reactor Ceramic membrane

黄河下游豫鲁地区创新网络时空演化及环境效应研究

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河南师范大学学报（自然科学版） 2025年第1期53卷 1-12,F0002页

作者：刘建华赵鼎葛世帅黄亮朝崔源郑州大学管理学院郑州450001 郑州大学黄河生态保护与区域协调发展研究院郑州450001 河南交通职业技术学院交通信息工程系郑州450000

创新是城市与区域发展的核心动力,创新网络是提升区域创新能力的重要支撑.以黄河下游豫鲁地区为研究对象,采用修正后的引力模型来构建城市间的创新关联网络,运用社会网络分析法探究2014-2022年空间关联网络的演化与特征,并探析黄河下游... 详细信息

创新是城市与区域发展的核心动力,创新网络是提升区域创新能力的重要支撑.以黄河下游豫鲁地区为研究对象,采用修正后的引力模型来构建城市间的创新关联网络,运用社会网络分析法探究2014-2022年空间关联网络的演化与特征,并探析黄河下游豫鲁地区创新网络对环境的影响.研究发现,整体来看,黄河下游豫鲁地区整体创新网络发展水平逐步提高,但空间分布不均的特征明显,创新网络整体发展水平仍处于起步阶段;分区域来看,河南省创新网络水平存在严重的两极分化现象,在空间上呈“米”字形分布.山东省整体创新网络水平高于河南省,创新资源分布较为均衡;研究期内,郑州、济南、青岛等城市是网络中的溢出主体,其中郑州、青岛是网络中的关键节点,影响整个网络稳定性.此外,研究区凝聚子群呈现出以郑州、济南、青岛为引领的“三核心”创新网络格局,但子群倾向于“抱团”,行政壁垒尚未消除;黄河下游豫鲁地区创新网络与环境污染呈倒“U”型关系,当创新网络水平跨过“拐点”时,才会对环境污染产生抑制作用,从而有效改善环境质量.在创新网络发展初期,开放程度、经济水平和人口规模扩大会加剧环境污染程度,而环境治理支出的增长和产业结构的优化能有效抑制环境污染.

关键词：黄河下游豫鲁地区空间联系网络引力模型社会网络分析环境污染

Estimation of copper concentration of rocks using hyperspectral technology

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Frontiers of Earth Science 2019年第3期13卷 563-574页

作者： Shichao cui Kefa ZHOU Rufu ding State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Mineral Resources and Digital Geology Urumqi 830011China Xinjiang Research Center for Mineral Resources Chinese Academy of SciencesUrumqi 830011China University of the Chinese Academy of Sciences Beijing 100049China China Non-Ferrous Metals Resources Geological Survey Beijing 100012China

Rock geochemical information is important for mineral exploration and provides a theoretical basis for the rapid delineation of hidden minerals. Remote sensing technology provides the possibility of rapid and large-scale extraction of geochemical information from the earth’s surface. This study analyzed the relationship between copper concentration and rock spectra by first collecting 222 rock samples, and then measuring the copper concentration of rock samples in the laboratory and reflectance spectra using an ASD FieldSpec3 portable spectrometer. It finally established quantitative relationships between the original spectra, first-order derivative spectra and second-order derivative spectra and copper concentration, respectively, using the partial least squares support vector machine method (PLS-SVM). The results show that 1) The estimation accuracy of using second-order derivatives spectra as input parameters to establish a model for estimating copper concentration is the highest, and the determined coefficient (R2) between the predicted value and real value reaches 0.54. 2) When the copper concentration is less than 80 mg/kg, the inversion model of copper concentration established using PLS-SVM obtains a good result. The R2 between the predicted copper concentration and the real copper concentration reached 0.70248. When the copper concentration is greater than 80 mg/kg, the inversion model of copper concentration established using partial least squares (PLS) obtains a good result. The R2 between the predicted copper concentration and the real copper concentration reached 0.49. The R2 between real copper concentration and copper predicted by the method of piecewise separate modeling reaches ***, the method of segmental modeling has great potential to improve the accuracy of copper concentration inversion.

关键词： copper concentration rock geochemical information PLS-SVM remote sensing

轻度认知障碍老人与认知正常老人在不同单双任务下姿势控制能力的差异性

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中国组织工程研究 2025年第8期29卷 1643-1649页

作者：张雨馨于聪张翠丁建军陈岩山东体育学院山东省济南市250102 山东省体育科学研究中心山东省济南市250102 山东体育学院运动与健康学院山东省济南市250102

背景:老年人由于轻度认知障碍而引起姿势控制能力下降,导致跌倒风险增高。双任务是在接近真实生活场景下评估认知与姿势控制能力关系的主要研究范式,站立时足底压力中心位移样本熵可代表姿势控制的复杂程度。目的:基于压力中心位移样本... 详细信息

背景:老年人由于轻度认知障碍而引起姿势控制能力下降,导致跌倒风险增高。双任务是在接近真实生活场景下评估认知与姿势控制能力关系的主要研究范式,站立时足底压力中心位移样本熵可代表姿势控制的复杂程度。目的:基于压力中心位移样本熵分析轻度认知障碍老年人与认知正常老年人在姿势控制-空间工作记忆任务中姿势稳定性特征及控制策略的差异,探究认知功能损伤对站立姿势控制能力影响。方法:筛选出符合条件的16名轻度认知障碍老年人和17名认知正常老年人为研究对象,老年人分别完成5种测试任务,包括空间工作记忆、双脚平衡站立、Romberg站立、双脚平衡站立-空间工作记忆双任务、Romberg站立-空间工作记忆双任务,每个任务有效完成3次。使用Kistler三维测力台采集足底压力中心数据,测试指标包括认知行为学指标(认知得分与反应时长)、动力学指标(压力中心位移及样本熵)。结果与结论:①轻度认知障碍老年人在执行空间工作记忆任务时认知得分最大、反应时间最短,双脚平衡站立-空间工作记忆双任务居中,Romberg站立-空间工作记忆双任务认知得分最小、反应时长最长,任务间比较差异均有显著性意义(P0.05);在两种双任务下,与认知正常老年人相比,轻度认知障碍老年人的认知得分更小、反应时长更长(P<0.05),同时轻度认知障碍老年人压力中心前后、内外方向位移更大,压力中心前后、内外方向位移样本熵值更小(P<0.05);④结果表明:与认知正常老年人相比,轻度认知障碍老年人在执行双任务时姿势控制复杂度降低,系统适应性较差,自动调控能力下降,更容易受到空间工作记忆干扰,跌倒风险增大。

关键词：轻度认知障碍老年人空间工作记忆姿势控制双任务样本熵

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Research in Astronomy and Astrophysics 2014年第9期14卷 1055-1060页

作者： ding-Qiang Su Xiang-Qun cui Department of Astronomy Nanjing University Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education National Astronomical Observatories/Nanjing Institute of Astronomical Optics and Technology(NIAOT) Chinese Academy of Sciences

China will establish a 2-meter space-based astronomical telescope. Its main science goals are performing a sky survey for research about dark matter and dark energy, and high resolution observations. Some experts suggest that this space telescope should be installed inside the Chinese space station. In accord with this suggestion we put forward our first configuration, i.e., to adopt a coude system for this telescope. This coude system comes from the Chinese 2.16 m telescope＇s coude system, which includes a relay mirror so that excellent image quality can be obtained. In our second configuration, we suggest that the whole space telescope fly freely as an independent satellite outside the space station. When it needs servicing, for example, changing in- struments, refilling refrigerant or propellant, etc., this space telescope can fly near or even dock with the core space station. Although some space stations have had accom- panying satellites, the one we propose is a space telescope that will be much larger than other accompanying satellites in terms of weight and volume. On the basis of the second configuration, we also put forward the following idea： the space station can be composed of several large independent modules if necessary.

关键词： instruments -- space telescope -- space station -- survey -- high angu- lar resolution