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Neural Regeneration Research 2017年第10期12卷 1613-1615页

作者： Dan C.li qun li Department of Neuroscience Emory University School of Medicine Department of Anesthesiology and Critical Care Medicine Johns Hopkins University School of Medicine

Background and early studies： Endogenous tri-potential neural stem cells （NSCs） exist in the adult mammalian central nervous system （CNS）. In the spinal cord, NSCs distribute throughout the entire cord, but exist predominately in white matter tracts. The phenotypic fate of these cells in white matter is glial, largely oligodendrocyte, but not neuronal.

关键词： OPC CNS Electrical stimulation of cortical neurons promotes oligodendrocyte development and remyelination in the injured spinal cord

Microstructure and Thermal-protective Property of CPED Coating with ZrO2 Nanoparticles Addition on Al-12Si Alloy

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1187-1192页

作者： WANG Ping MA qun li Bin li Yaoyao Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices School of Materials and Chemical Engineering Xi’an Technological University

A novel thermal-protective coating has been successfully prepared by CPED process on a cast Al-12%Si alloy with the addition of ZrO2 nano-particles in the electrolyte. The microstructures and phase composition of the coatings were analyzed by SEM and XRD, and the heat insulation performance and the thermal shock resistance of the coatings were investigated. With ZrO2 nanoparticles addition, the cathode plasma discharge on the coating surface is more obvious than that without ZrO2 nanoparticles addition, the coating is more uniform and compact, and the thickness of the coating increases. Furthermore, the content of Zr and Y elements increases and the degree of crystallization of the coating is more complete. The formation of the solid solution of yttrium stabilized zirconia is promoted by cathode plasma discharge. In addition, the thermal insulation temperature increases as ZrO2 nano-particles are added to the electrolyte. After 1 000 cycles of thermal shock, there was no cracking in the coating surface layer, which indicated that the CPED coating with ZrO2 nanoparticles addition possessed a good thermal shock resistance.

关键词： Al-12Si piston alloy cathode plasma electrolytic deposition(CPED) ZrO2 nanoparticles heat-shielding performance thermal shock performance

A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl_4/SiO_2

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Chinese Chemical Letters 2001年第7期12卷 565-568页

作者： Yi qun li li Hui CHENG Department of Chemistry Jinan UniversityGuangzhou 510632

A variety of aldehydes were converted into acylals in excellent yields with acetic anhydride in the presence of a catalytic amount of tin (IV) chloride supported on silica gel at room temperature.

关键词： Acylals tin (IV) chloride supported on silica gel

Structures of sodium vanadate solution under different conditions

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Rare Metals 2018年第1期37卷 59-65页

作者： Ya-li Zhang li-qun Yang Xian-Jin Yu School of Chemical Engineering Shandong University of Technology

Combined with Fourier transform infrared spectroscopy（FTIR） analysis of sodium vanadate solution,the relationship between conductivity and structure was investigated by measuring the electric conductivity of the solution under different alkali concentrations and molar ratios of NaOH to V2O5. Results suggest that the polymerization vanadium acid radical ions gradually transform into monomer with the solution diluting. When the solution is diluted to a certain extent,only the vanadium acid radical ion with V-OH chemical bond exists in the solution. At NaOH concentration of below 105.21 g·L^（-1）,the vanadate anions mainly exist in the form of vanadium acid radical ion with V-OH chemical bond and the ion transference number is approximately from 0.58 to 0.82. In the medium NaOH concentration range of 105.21-117.03 g·L^（-1）, the vanadate anions mostly exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds and the ion transference number is approximately 3.29. At NaOH concentration of above 117.03 g·L^（-1）, vanadate anions exist in the form of vanadium acid radical ion with V-OH and V-O-V chemical bonds.

关键词： Sodium vanadate solution Electric conductivity Migration number Infrared spectroscopy

Potassium iodide catalyzed reductive dehalogenation ofα-halo-ketones using Hantzsch ester diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate as reductant

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Chinese Chemical Letters 2010年第8期21卷 931-934页

作者： Hong Sheng li Yi qun li Department of Chemistry Jinan UniversityGuangzhou 510632China

In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone *** procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.

关键词： Dehalogenation α-Halo ketones Hantzsch ester 1 4-Dihydro-2 6-dimethylpyridine-3 5-dicarboxylate Potassium iodide

CHAOS IN PERTURBED PLANAR NON-HAMILTONIAN INTEGRABLE SYSTEMS WITH SLOWLY-VARYINGANGLE PARAMETERS

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Applied Mathematics and Mechanics(English Edition) 2001年第11期22卷 1301-1305页

作者： CHEN li-qun(陈立群) Shanghai Institute of Applied Mathematics and Mechanics Shanghai 200072 P R China

The Melnikov method was extended to perturbed planar non-Hamiltonian integrable systems with slowly-varying angle parameters. Based on the analysis of the geometric structure of unperturbed systems, the condition of transversely homoclinic intersection was established. The generalized Melnikov function of the perturbed system was presented by applying the theorem on the differentiability of ordinary differential equation solutions with respect to parameters. Chaos may occur in the system if the generalized Melnikov function has simple zeros.

关键词： Melnikov method perturbed integrable system transversely homoclinic chaos

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面向无人机载平台的轻量级小目标检测算法

河南大学学报(自然科学版) 2025年第1期 1-11页

作者：党兰学李赞苗长伟崔金华赵雅靓河南大学河南省大数据分析与处理重点实验室河南开封475004 中核勘察设计研究有限公司郑州475000 华中科技大学计算机与信息工程学院武汉430074 河南大学计算机与信息工程学院河南开封475004

无人机载平台中的目标检测在军事和民用领域具有重要的应用价值.然而,现有的检测方法通常侧重于多尺度目标检测,缺乏对小目标的优化,且模型复杂度过高,难以在资源受限的机载平台中应用.为此,本文提出了一种面向无人机载平台的轻量级小... 详细信息

无人机载平台中的目标检测在军事和民用领域具有重要的应用价值.然而,现有的检测方法通常侧重于多尺度目标检测,缺乏对小目标的优化,且模型复杂度过高,难以在资源受限的机载平台中应用.为此,本文提出了一种面向无人机载平台的轻量级小目标检测算法YOLOH(You Only Look One Head).首先,针对小目标对基准网络优化,移除深层特征以减少模型参数量,增加浅层特征以获取小目标信息.其次,在特征融合部分加入NAM注意力,增强对小目标的感知能力.接着,设计了多感受野聚焦模块MRFF,以挖掘特征图的感受野信息,增强模型的多尺度检测能力.最后,使用LAMP算法对模型剪枝,去除冗余神经元以压缩模型.实验结果表明,与YOLOv8s相比,YOLOH的模型参数量和计算量分别减少了92%和35%,FPS提高了57%.在VisDrone2019和CARPK数据集上AP_(S)分别提高了3.3%和3.7%.与其他轻量级模型相比,所提YOLOH具有最佳的整体性能,同时平衡了模型大小、精度和推理速度,为无人机载平台的目标检测提供了有效的解决方案.

关键词：机载平台 YOLOH 小目标检测轻量级多感受野

地铁列车荷载作用下文物建筑动力响应预测与分析

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铁道标准设计 2025年第2期69卷 198-205页

作者：阮莹党红玲齐英睿冯青松李平广州地铁设计研究院股份有限公司广州地铁集团有限公司华东交通大学轨道交通基础设施性能监测与保障国家重点实验室

为预测地铁列车荷载作用下广州地区某砖混结构省级文物建筑群的动力响应特性，综合运用现场试验与数值模拟相结合的方法，获得该文物建筑群所在线路区间断面的振动源强特性、地面振动传播规律以及盾构施工期的振动响应，通过建立“车辆... 详细信息

为预测地铁列车荷载作用下广州地区某砖混结构省级文物建筑群的动力响应特性，综合运用现场试验与数值模拟相结合的方法，获得该文物建筑群所在线路区间断面的振动源强特性、地面振动传播规律以及盾构施工期的振动响应，通过建立“车辆-轨道-隧道-大地-建筑物”预测模型，评估最不利工况下列车荷载对文物建筑群的影响。研究表明，类比断面的钢轨、道床和隧道壁加速度峰值均值分别为311.33,2.11,1.77 m/s2,隧道内振动在1～400 Hz频段整体呈现递增趋势，主频段在63～100 Hz;地面振动以低频为主，振动在近场横向传递过程中，呈现先增后减的趋势，优势频率在10～16 Hz、40～63 Hz;盾构施工引起的文物建筑振动主频在40 Hz和60 Hz附近，与非施工时段背景振动相比，盾构施工引起的文物建筑三向振动速度分别增大10.4,19.7,12.3倍；列车荷载作用下，文物建筑楼板振动为低频振动，主频分布在40～60 Hz,顶层测点的水平向振动速度在一定范围内存在振动放大现象，双线运行引起的顶层振动速度较单线时增大426.89%和181.32%,预测列车荷载对文物建筑影响时需特别关注此工况。最不利工况下，两栋文物建筑顶层测点的振动速度峰值是容许振动限值的23.22%和18.96%,满足防振技术规范的限值要求。

关键词：地铁列车文物建筑类比测试动力响应数值分析

Electrochemical Behavior of Oxide Films of Stainless Steel in 40 kHz Sonicated Sulphate Electrolytes

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Chinese Journal of Aeronautics 2007年第2期20卷 148-152页

作者： ZHU li-qun li Min-wei WANG Hui School of Materials Science and Engineering Beij＇ing University of Aeronautics and Astronautics Beijing 100083 China Shenyang liming Aero-Engine Group Corporation Shenyang 110043 China

This paper describes effects of 40 kHz ultrasound on the oxide films of stainless steel in sulphate electrolytes so as to determine the transmitted power and to characterize mass transfer and peak current density on the electrode surface. Emphasis was mainly laid on electrochemical oxidations and peeling mechanism of oxide films in sonicated sulphate solutions （0.5 and 1.0 mol/L）. Polarization voltammetry, current response traces and SEM analysis were carded out in order to provide full information as to oxide films surface. Results shows that the rate of electrochemical oxidation, the shape of polarization curves and the surface micrographs in sonicated sulphate electrolytes are different from those obtained without introduction of ultrasound. It is concluded that ultrasound can change the electro-chemical behavior of oxide films by its cavitaion effects, which would produce transient mechanical impulsive force and enhance electrochemical reactions.

关键词： stainless steel oxide films electrolysis ultrasound cavitation

An Improved Kalman Filter Positioning Method in NLOS Environment

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China Communications 2019年第12期16卷 84-99页

作者： Zhanjun Hao Beibei li Xiaochao dang College of Computer Science and Engineering Northwest Normal UniversityLanzhou 730070China Gansu Province Internet of Things Engineering Research Center Lanzhou 730070China

In the precision positioning system, NLOS(Non line of Sight) propagation and clock synchronization error caused by multiple base stations are the main reasons for reducing the reliability of communication and positioning accuracy. So, in the NLOS environment, it has an important role to eliminate the clock synchronization problem in the positioning system. In order to solve this problem, this paper proposes an improved Kalman filter localization method NLOS-K(Non line of Sight-Kalman filter). First, the maximum likelihood estimation algorithm is used to iterate. Then, the Kalman filter algorithm is implemented and the Kalman gain matrix is redefined. The clock drift is compensated so that the clock between the master and slave base stations remains synchronized. The experimental results show that in the non-lineof-sight environment, compared with other algorithms, the positioning accuracy error of the improved algorithm is about 5 cm, and the accuracy compared with other algorithms is 97%. In addition, the influence of bandwidth and spectral density on the method is analyzed, and the accuracy and stability of positioning are improved as a whole.

关键词： NLOS clock synchronization Kalman filtering maximum likelihood estimation spectral density