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Chinese Journal of Aeronautics 2021年第4期34卷 192-207页

作者： Tingzhang WANG Henan LIU chunya.WU Jian chen Mingjun chen Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

As for ultra-precision grinding of difficult-to-process thin-walled complex components with ball-end grinding wheels,interference is easy to *** to screw theory and grinding kinematics,a mathematical model is established to investigate the interference and grinding characteristics of the ball-end *** relationship between grinding wheel inclination angle,C axis rotation angle,grinding position angle and grinding wheel wear are *** the grinding wheel inclination angle increases,the C axis rotatable range decreases and the grinding position angle *** grinding position angle and wheel radius wear show a negative correlation with the C axis rotation ***,a trajectory planning criteria for increasing grinding speed as much as possible under the premise of avoiding interference is proposed to design the grinding *** grinding point distribution on the ball-end wheel is calculated,and the grinding characteristics,grinding speed and maximum undeformed chip thickness,are ***,a complex structural component can be ground without interference,and surface roughness and profile accuracy are improved to 40.2 nm and 0.399 lm,compared with 556 nm and 3.427 lm before ultra-precision *** mathematical model can provide theoretical guidance for the analysis of interference and grinding characteristics in complex components grinding to improve its grinding quality.

关键词： Ultra-precision grinding Complex component Ball-end grinding wheel Interference Grinding characteristics

Theoretical and Experimental Research on Error Analysis and Optimization of Tool Path in Fabricating Aspheric Compound Eyes by Precision Micro Milling

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 558-566页

作者： chen Mingjun XIAO Yong TIAN Wenlan WU chunya.CHU Xin Center for Precision Engineering Harbin institute of technology

Structure design and fabricating methods of three-dimensional （3D） artificial spherical compound eyes have been researched by many scholars. Micro-nano optical manufacturing is mostly used to process 3D artificial compound eyes. However, spherical optical compound eyes are less at optical performance than the eyes of insects, and it is difficult to further improve the imaging quality of compound eyes by means of micro-nano optical manufacturing. In this research, nonhomogeneous aspheric compound eyes （ACEs） are designed and fabricated. The nonhomogeneous aspheric structure is applied to calibrate the spherical aberration. Micro milling with advantages in processing three-dimensional micro structures is adopted to manufacture ACEs. In order to obtain ACEs with high imaging quality, the tool paths are optimized by analyzing the influence factors consisting of interpolation allowable error, scallop height and tool path pattern. In the experiments, two kinds of ACEs are manufactured by micro-milling with different too path patterns and cutting parameter on the miniature precision five-axis milling machine tool. The experimental results indicate that the ACEs of high surface quality can be achieved by circularly milling small micro-lens individually with changeable cutting depth. A prototype of the aspheric compound eye （ACE） with surface roughness （Ra） below 0.12 p.m is obtained with good imaging performance. This research ameliorates the imaging quality of 3D artificial compound eyes, and the proposed method of micro-milling can improve surface processing quality of compound eyes.

关键词： aspheric compound eyes (ACEs) micro milling tool path optimization

Research on the influence of machining introduced sub-surface defects and residue stress upon the mechanical properties of single crystal copper

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Science China(Technological Sciences) 2010年第12期53卷 3161-3167页

作者： chen MingJun, XIAO GaoBo, chen JiaXuan & WU chunya.Harbin Institute of Technology, Harbin 150001, China 1. Harbin Institute of Technology Harbin 150001 China

Large scale molecular dynamics simulations of nanomachining and stretching of single crystal copper are performed to analyze the machining process’ influence on the material’s mechanical properties. The simulation results show that the machining process will introduce interfacial defects inside the specimen and enhance the compressive stress beneath the surface. Gener- ally speaking, interfacial defects lead to the decrease of the strength limit, while residue compressive stress can enhance the elastic limit and even the strength limit. Various machining parameters are adopted to investigate their influence on the me- chanical behavior of machined specimen. Lower cutting speed and smaller cutting depth lead to less defects and greater residue compressive stress, which brings about better mechanical properties. The elastic limit increases by 36.8% under the cutting depth of 0.73 nm and decreases by 21.1% under the cutting depth of 1.46 nm. The strength limit increases by 7.7% under the cutting speed of 100 m/s and decreases by 28.2% under the cutting speed of 300 m/s.

关键词： nanomachining deformation residue stress molecular dynamics dislocations

Walking Cations: Transition-Metal Free Benzyl Cation-Triggered sp^(2) C—H Phosphorylation and Etherification

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Chinese Journal of Chemistry 2022年第24期40卷 2933-2938页

作者： Kuan Liu Bin Song Qi Dang Long Liu Jie Tang Tianzeng Huang chunya.Li Zhi Tang Tieqiao chen Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources Hainan Provincial Key Lab of Fine ChemHainan Provincial Fine Chemical Engineering Research CenterHainan UniversityHaikouHainan570228 China

A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.

关键词： Transition metal-free Cation migration Site-selectivity Phosphorylation Etherification

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高比例新能源送端系统暂态电压运行风险分析

电力系统保护与控制 2024年第1期52卷 23-34页

作者：韩璐尹纯亚戴晨马星新疆大学电气工程学院新疆乌鲁木齐830017 中电建湖北电力勘测设计院规划分院研究院湖北武汉430000 国网新疆电力有限公司电力科学研究院新疆乌鲁木齐830011

针对交、直流故障下的高比例新能源送端系统暂态电压演化传播机理及运行风险尚不明晰的问题,首先,基于交直流系统间的无功电压交互作用机理分析,明确了交、直流系统故障下的暂态电压特性及主导影响因素,阐明了高比例新能源送端系统电力... 详细信息

针对交、直流故障下的高比例新能源送端系统暂态电压演化传播机理及运行风险尚不明晰的问题,首先,基于交直流系统间的无功电压交互作用机理分析,明确了交、直流系统故障下的暂态电压特性及主导影响因素,阐明了高比例新能源送端系统电力电子设备主导的暂态电压演化传播路径。其次,从“交直流故障强耦合作用持续加强,暂态无功功率成分复杂”、“新能源比例不断提升,暂态电压问题凸显”及“故障承载与调节能力下降,连锁脱网风险增大”三方面系统地阐述了暂态电压运行风险。然后,基于DIgSILENT/PowerFactory建立了实际高比例新能源多直流外送系统仿真模型,不同新能源占比、不同故障工况下的仿真结果验证了暂态电压运行风险分析的正确性。最后,从增强耦合运行特性机理认识、提升新能源涉网性能、增加多尺度协同控制策略、加强交流网架结构等方面提出了应对暂态电压运行风险的技术展望。

关键词：高比例新能源送端系统交直流故障暂态电压运行风险

Coating Process of Paeonol Sustained Release Pills

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Medicinal Plant 2023年第4期14卷 46-50页

作者： chunya.ZHOU Huimin chen Liuliu LIU Yanlin HUANG Wenyu LUO Meijia CAI Fei HAN School of Pharmacy Jiangxi University of Traditional Chinese MedicineNanchang 330004China

[Objectives] To study the coating process of paeonol sustained release pills by extrusion-spheronization method taking ethyl cellulose as the coating material. [Methods] Paeonol pills were made by Auari AW-95 Full Automatic Pill Making Machine. Coating of paeonol sustained release pills was prepared by Auari Mini Pill Polishing Machine. The prescription and process factors of paeonol sustained release pills coating were investigated by single factor experiment and orthogonal experiment. The release of paeonol sustained release pills was determined according to the cumulative release curve of paeonol. [Results] The prepared paeonol sustained release pills released slowly within 24 h, and the release rate reached 80% in 12 h. [Conclusions] The prepared paeonol sustained release pills basically meet the 24 h sustained release standard, and can be further developed and applied.

关键词： Paeonol Sustained release pills Coating Ethyl cellulose Release

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面向中国-东盟的智库情报体系构建研究

情报杂志 2018年第8期37卷 18-22,31页

作者：陈璟浩李春雅广西大学公共管理学院南宁530004 南通理工学院商学院南通226002

[目的/意义]情报工作在中国-东盟智库研究咨询过程中发挥着重要的基础作用,建立面向中国-东盟的智库情报体系,有助于推动和促进中国-东盟智库建成国家高水平智库。[方法/过程]从情报视角出发,提出了面向中国-东盟的智库情报体系定位、... 详细信息

[目的/意义]情报工作在中国-东盟智库研究咨询过程中发挥着重要的基础作用,建立面向中国-东盟的智库情报体系,有助于推动和促进中国-东盟智库建成国家高水平智库。[方法/过程]从情报视角出发,提出了面向中国-东盟的智库情报体系定位、目标和功能,阐述了情报体系的基本要素,在此基础上,构建了面向中国-东盟的智库情报体系框架,厘清了情报体系的运行机制,探讨了情报体系的保障机制。[结果/结论]该情报体系实现了情报的采集、处理、存储、分析和服务功能,能满足当前及今后一段时间智库对情报工作的要求。

关键词：智库中国-东盟情报体系

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单极闭锁引起直流健全极换相失败分析

电力自动化设备 2019年第11期39卷 114-119,132页

作者：尹纯亚李凤婷陈伟伟张增强新疆大学电气工程学院新疆乌鲁木齐830047 国网新疆电力公司经济技术研究院新疆乌鲁木齐830011

推导建立了换相失败的数学模型,得出送、受端换流母线电压比值是引起换相失败的主要原因,单极闭锁后健全极存在换相失败的风险。分析了单极闭锁引起暂态过电压的影响因素,并推导出直流闭锁后的暂态过电压定量计算解析表达式,提出一种单... 详细信息

推导建立了换相失败的数学模型,得出送、受端换流母线电压比值是引起换相失败的主要原因,单极闭锁后健全极存在换相失败的风险。分析了单极闭锁引起暂态过电压的影响因素,并推导出直流闭锁后的暂态过电压定量计算解析表达式,提出一种单极闭锁后考虑两侧换流母线电压的换相失败判据,并得出送端、受端短路容量与换相失败的关系。最后基于DIgSILENT仿真平台搭建±800 kV天中直流输电系统仿真模型,仿真结果验证了暂态过电压计算方法的正确性,同时证明了单极闭锁后健全极存在换相失败的风险。

关键词：高压直流输电电力传输换相失败单极闭锁暂态过电压关断角

基于无功功率短路比的直流闭锁暂态过电压计算方法

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电力系统自动化 2019年第10期43卷 150-157,161页

作者：尹纯亚李凤婷周识远陈伟伟新疆大学电气工程学院新疆维吾尔自治区乌鲁木齐市830047 国网甘肃省电力有限公司风电技术中心甘肃省兰州市730050 国网新疆电力有限公司经济技术研究院新疆维吾尔自治区乌鲁木齐市830011

针对现有特高压直流闭锁引起交流系统换流母线暂态过电压计算方法在极低短路比情况下可能无实解的问题,基于直流闭锁后的谐振电路,推导建立了暂态过电压与谐振频率的关系式。参照短路比的定义,提出无功功率短路比的概念,在此基础上,提... 详细信息

针对现有特高压直流闭锁引起交流系统换流母线暂态过电压计算方法在极低短路比情况下可能无实解的问题,基于直流闭锁后的谐振电路,推导建立了暂态过电压与谐振频率的关系式。参照短路比的定义,提出无功功率短路比的概念,在此基础上,提出适用范围更广的直流闭锁暂态过电压计算方法。研究发现,换流母线暂态过电压随着无功功率短路比的减小呈非线性加速上升的趋势。以DIgSILENT为平台搭建国际大电网会议(CIGRE)直流输电标准测试系统与±800 kV天中直流送端系统,仿真分析验证了所提出的暂态过电压计算方法的有效性,在极低短路比系统中仍然适用。

关键词：特高压直流直流闭锁暂态过电压无功功率短路比

RGD与特定形貌金红石表面相互作用的分子动力学模拟

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化工学报 2017年第1期68卷 199-207页

作者：吴春亚郭闯强郑庭陈妮陈明君赫晓东哈尔滨工业大学材料科学与工程博士后流动站黑龙江哈尔滨150001 哈尔滨工业大学机电工程学院黑龙江哈尔滨150001

精氨酸–甘氨酸–天冬氨酸(Arg-Gly-Asp,RGD)序列是细胞膜整合素受体与细胞外配体相结合的识别位点,利用其对材料表面进行仿生修饰可以提高植入体的生物相容性。采用全原子分子动力学方法,模拟研究了RGD与理想和具有不同深度凹槽结构的... 详细信息

精氨酸–甘氨酸–天冬氨酸(Arg-Gly-Asp,RGD)序列是细胞膜整合素受体与细胞外配体相结合的识别位点,利用其对材料表面进行仿生修饰可以提高植入体的生物相容性。采用全原子分子动力学方法,模拟研究了RGD与理想和具有不同深度凹槽结构的金红石型TiO_2(110)表面的结合模式和结合稳定性。研究结果表明,在纯水环境下,RGD在金红石表面存在锚定点是该序列中带负电的羧基基团与表面Ti原子直接键合的前提。凹槽侧壁表层的不饱和原子是RGD形成吸附的潜在作用点,故在金红石表面引入凹槽结构能在一定程度上影响该序列同基底之间的结合模式。当RGD通过羧基基团与槽底原子稳定键合之后,若剩余部分的长度足以触及至槽壁区域,则肽链中带正电的氨基或胍基基团与槽壁原子形成氢键的概率较大;若RGD通过两侧末端基团分别同槽底形成了稳定作用,则会显著抑制该序列与槽壁原子之间氢键的形成。RGD序列同金红石表面结合作用的强弱取决于结合点的数量以及相互作用的具体类型。

关键词：金红石表面拓扑结构肽分子模拟水溶液