检索结果-南通市图书馆

Energy beam-based direct and assisted polishing techniques for diamond:A review

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 93-124页

作者： Zhuo Li Feng jiang zhengyi jiang Zige Tian Tian Qiu Tao Zhang Qiuling Wen Xizhao Lu Jing Lu Hui Huang Institute of Manufacturing Engineering Huaqiao UniversityXiamen 361021People’s Republic of China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia College of Mechanical Engineering and Automation Huaqiao UniversityXiamen 361021People’s Republic of China State Key Laboratory of High Performance Tools Huaqiao UniversityXiamen 361021People’s Republic of China

Diamond is a highly valuable material with diverse industrial applications,particularly in the fields of semiconductor,optics,and high-power electronics.However,its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of diamond.To address these challenges,several polishing methods have been developed for both single crystal diamond(SCD)and polycrystalline diamond(PCD),including mechanical,chemical,laser,and ion beam processing methods.In this review,the characteristics and application scope of various polishing technologies for SCD and PCD are highlighted.Specifically,various energy beam-based direct and assisted polishing technologies,such as laser polishing,ion beam polishing,plasma-assisted polishing,and laser-assisted polishing,are summarized.The current research progress,material removal mechanism,and infuencing factors of each polishing technology are analyzed.Although some of these methods can achieve high material removal rates or reduce surface roughness,no single method can meet all the requirements.Finally,the future development prospects and application directions of different polishing technologies are presented.

关键词： single crystal diamond polycrystalline diamond energy beam polishing technology material removal mechanism influencing factors

在线全文

学校读者我要写书评

暂无评论

抛浆除鳞工艺中氧化皮去除模型研究

湖南大学学报（自然科学版） 2024年第4期51卷 114-122页

作者：柴泽琳周存龙郭瑞姜正义太原科技大学机械工程学院山西太原030024 伍伦贡大学澳大利亚伍伦贡NSW2522

针对抛浆除鳞缺乏精确的氧化皮去除量与工艺参数相关数学模型的问题,以Q235热轧板带表面氧化皮为研究对象,依据能量守恒分析抛浆工艺中磨粒与水的混合浆体在冲击过程中的动能变化规律,根据应变能理论分析基体表面氧化皮在浆体冲击后的... 详细信息

针对抛浆除鳞缺乏精确的氧化皮去除量与工艺参数相关数学模型的问题,以Q235热轧板带表面氧化皮为研究对象,依据能量守恒分析抛浆工艺中磨粒与水的混合浆体在冲击过程中的动能变化规律,根据应变能理论分析基体表面氧化皮在浆体冲击后的应变能变化规律,建立氧化皮去除量与抛浆工艺参数之间的数学模型.利用光滑粒子流体动力学,采用有限元ANSYS/AUTODYN模块,对抛浆过程中氧化皮与基体变形的过程进行模拟,采用抛、喷浆一体化除鳞实验平台进行抛浆除鳞实验.结果表明,当基体表面氧化皮应变高于临界应变时,氧化皮会破裂剥落;磨粒粒径对冲击范围增加率的影响与冲击速度的比值为105.35%∶24.14%,磨粒粒径对冲击深度增加率的影响与冲击速度的比值为233.67%∶5.86%,冲击范围有限元计算结果与实验结果最大偏差率为8.71%,冲击深度最大偏差率为8.55%.磨粒冲击次数解析法、有限元计算结果与实验结果一致,利用304不锈钢和45钢的抛浆除鳞实验结果验证了模型的广泛适用性.

关键词：抛浆应变去除量冲击深度冲击范围

Molecular Dynamics Simulation on Mobility and Aggregation of Macromolecular Lubricant Oxidation Products and Their Influences on Base Stock

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2020年第3期22卷 101-108页

作者： Xia Lei Li Yan Zhang Hongmei jiang zhengyi Long Jun School of Material and Metallurgy University of Science and Technology LiaoningAnshan 114051 State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009 Iron&Steel Research Institutes of Ansteel Group Corporation Anshan 114009 School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2522Australia SINOPEC Research Institute of Petroleum Processing Beijing 100083

The mobility and aggregation behavior of macromolecular lubricant oxidation products and their influences on the performance of base stock were probed by molecular dynamics(MD)simulation.The mean square displacement(MSD)of molecules was calculated to explore the mobility of molecules.The distribution appearance of lubricant oxidation products in models was acquired to explore the aggregation of molecules.The results show that the mobility of macromolecular oxidation products is lower than that of base stock.The MSD of macromolecular oxidation products reduces with an increasing macromolecular weight.Macromolecular oxidation products can also decrease the mobility of base stock.The interaction energy between the macromolecules and the base stock soars with the increase of macromolecular weight.Macromolecules with a larger molecular weight can affect more base stock molecules with stronger restriction,which leads to lower mobility of base stock molecules.There are aggregates formed among macromolecular oxidation products,and the molecules in aggregates are connected by hydrogen bonds.The quantity of hydrogen bonds in aggregates is related to temperature.

关键词： molecular dynamics simulation lubricant oxidation aggregation mobility

Molecular Simulation of Chain Initiation Mechanism in Oxidation of Lubricant Base Stock

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2021年第4期23卷 105-112页

作者： Xia Lei Li Yan Zhang Hongmei jiang zhengyi Long Jun School of Material and Metallurgy University of Science and Technology LiaoningAnshan 114051 State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114009 Iron&Steel Research Institutes of Ansteel Group Corporation Anshan 114009 SINOPEC Research Institute of Petroleum Processing Beijing 100083

Chain initiation reactions in the oxidation process of lubricant base stock molecules were studied by molecular simulations.Two ways to initiate lubricant oxidation were investigated.They included the dissociation of chemical bonds in base stock molecules and the reaction between base stock molecules and oxygen(O_(2)),respectively.Reaction activation energy of above methods was calculated.The results show that C‒C bonds are more likely to break than C‒H bonds to generate free radicals by the pyrolysis of chemical bonds.The C‒C bonds with tertiary carbon atoms are preferential positions to crack.However,their bond dissociation energy is above 360 kJ/mol,which is difficult to occur under lubricant working conditions.The chain initiation is more likely to occur by the way that O_(2) attacks the two atoms in C‒H bonds at the same time,and is then embedded into the C‒H bond to produce hydrocarbon peroxides.And then,the O‒O bond is cracked to form hydroxyl radicals and alkoxy radicals.The C‒H bonds with tertiary carbon atoms are preferential reaction sites,the reaction activation energy of which is about 190.11 kJ/mol.

关键词： molecular simulation lubricant base stock oxidation chain initiation

Micro Extrusion of Ultrafine Grained Titanium Prepared by ECAP

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2017年第2期32卷 437-443页

作者：王效岗 LIU Jianlong ZHAO Xicheng LIU Xiaoyan XIE Haibo jiang zhengyi Shanxi Province Metallurgical Equipment Design Theory and Technology Key Laboratory (Provincial Department to Build National Key Laboratory Training Base) Taiyuan University of Science and Technology Taiyuan 030024 China Metallurgical Engineering College Xi'an University of Architecture and Technology Xi'an 710055 China School of Mechanical Materials and Mechatronic Engineering University of Wollongong Wollongong NSW 2522 Australia

Micro compression and micro extrusion experiments of ultrafine grained titanium cylindrical specimens in diameters of 4, 2, and 1 mm prepared by equal channel angular pressing（ECAP） were conducted on the micro plastic forming test machine. The effects of specimen size, grain size, deformation temperature and extrusion speed on the flow stress and forming properties of the ultrafine grained pure titanium were investigated. The flow stress of ultrafine grained pure titanium specimen decreases with decreasing specimen size. The yield limit of pure titanium with refined grain prepared by ECAP is significantly greater than that of coarse grained specimen. Also the research results show that the flow stress of specimen increases with decreasing deformation temperature and with the increase of the strain rate, and the ultrafine grained pure titanium possesses good micro forming properties at deformation temperature of 300 ℃.

关键词： micro forming ECAP pure titanium flow stress micro extrusion

Integrative Proteomic Analysis of Multiple Posttranslational Modifications in Inflammatory Response

在线全文

学校读者我要写书评

暂无评论

Genomics, Proteomics & Bioinformatics 2022年第1期20卷 163-176页

作者： Feiyang Ji Menghao Zhou Huihui Zhu zhengyi jiang Qirui Li Xiaoxi Ouyang Yiming Lv Sainan Zhang Tian Wu Lanjuan Li State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou 310003China Department of Colorectal Surgery Sir Run Run Shaw HospitalCollege of MedicineZhejiang UniversityHangzhou 310003China Quzhou Second People’s Hospital Quzhou 324000China

Posttranslational modifications(PTMs)of proteins,particularly acetylation,phosphorylation,and ubiquitination,play critical roles in the host innate immune response.PTMs’dynamic changes and the crosstalk among them are complicated.To build a comprehensive dynamic network of inflammation-related proteins,we integrated data from the whole-cell proteome(WCP),acetylome,phosphoproteome,and ubiquitinome of human and mouse macrophages.Our datasets of acetylation,phosphorylation,and ubiquitination sites helped identify PTM crosstalk within and across proteins involved in the inflammatory response.Stimulation of macrophages by lipopolysaccharide(LPS)resulted in both degradative and non-degradative ubiquitination.Moreover,this study contributes to the interpretation of the roles of known inflammatory molecules and the discovery of novel inflammatory proteins.

关键词： Proteome Crosstalk Inflammation Lipopolysaccharide Macrophage

Multimodal Fusion of Brain Imaging Data: Methods and Applications

在线全文

学校读者我要写书评

暂无评论

Machine Intelligence Research 2024年第1期21卷 136-152页

作者： Na Luo Weiyang Shi zhengyi Yang Ming Song Tianzi jiang Brainnetome Center and National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China Center for Excellence in Brain Science and Intelligence Technology Institute of AutomationChinese Academy of SciencesBeijing 100190China Research Center for Augmented Intelligence Zhejiang LaboratoryHangzhou 311100China

Neuroimaging data typically include multiple modalities,such as structural or functional magnetic resonance imaging,dif-fusion tensor imaging,and positron emission tomography,which provide multiple views for observing and analyzing the brain.To lever-age the complementary representations of different modalities,multimodal fusion is consequently needed to dig out both inter-modality and intra-modality information.With the exploited rich information,it is becoming popular to combine multiple modality data to ex-plore the structural and functional characteristics of the brain in both health and disease status.In this paper,we first review a wide spectrum of advanced machine learning methodologies for fusing multimodal brain imaging data,broadly categorized into unsupervised and supervised learning strategies.Followed by this,some representative applications are discussed,including how they help to under-stand the brain arealization,how they improve the prediction of behavioral phenotypes and brain aging,and how they accelerate the biomarker exploration of brain diseases.Finally,we discuss some exciting emerging trends and important future directions.Collectively,we intend to offer a comprehensive overview of brain imaging fusion methods and their successful applications,along with the chal-lenges imposed by multi-scale and big data,which arises an urgent demand on developing new models and platforms.

关键词： Multimodal fusion supervised learning unsupervised learning brain atlas cognition brain disorders

ANALYSIS OF MECHANICS IN BALL SPINNING OF THIN-WALLED TUBE

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2008年第1期21卷 25-30页

作者： jiang Shuyong REN zhengyi Engineering Training Center Harbin Engineering University Harbin 150001 China

Ball spinning is applied to manufacturing thin-walled tube with high precision and high mechanical properties. On the basis of plastic mechanics, by simplifying ball spinning of thin-walled tube as plane strain problem, slab method is used for the purpose of calculating the contact deformation pressure. The spinning force components, the torsional moment, the deformation power and the deformation work are calculated further as well. The influence of the two important process parameters such as the feed ratio and the ball diameter on the spinning force components is analyzed in order to further control the spinning force components by regulating the two process variables during the ball spinning process. The stress and strain state in deformable zone as well as mechanics boundary conditions in ball spinning are obtained. The effect of the three spinning force components on the formability of the spun part is analyzed and validated through the ball spinning experiments. The theoretical and experimental results show that the radial spinning component plays a significant role in ball spinning of thin-walled tube, and the mechanics situation in backward ball spinning contributes to enhancing the plasticity of the metal material, but that in forward ball spinning contributes to advancing the axial flow of the metal material.

关键词： Power spinning Tube spinning Ball spinning Spinning force Slab method

Stability-Considered Lane Keeping Control of Commercial Vehicles Based on Improved APF Algorithm

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2024年第1期37卷 114-129页

作者： Bin Tang zhengyi Yang Haobin jiang Ziyan Lin Zhanxiang Xu Zitian Hu Automotive Engineering Research Institute Jiangsu UniversityZhenjiang 212013China

Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving.

关键词： Lane keeping control Commercial vehicles Lateral stability Artificial potential field AIWPSO