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Design and Experimentation of a Novel Separable Vibration-Assisted Stage

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Nanomanufacturing and Metrology 2023年第3期6卷 41-50页

作者： Bowen Song Xiubing Jing Yingying ren Yongqin ren Huaizhong Li school of Mechanical Engineering Tianjin UniversityTianjin300354China Key Laboratory of Ocean Observation Technology Tianjin300000China Griffith school of Engineering Gold Coast CampusGriffith UniversitySouthportQLD4222Australia

In this paper,a novel,separable two-degrees-of-freedom stage with high-precision motion and resolution is proposed for the application of vibration-assisted micromilling.A separable design was realized on the basis of the detachable structure of the *** stages with different dimensions and types can be utilized in the devices.A circular-fillet hinge is selected as the flexible unit with a parallel structure to realize output decoupling and reduce the coupling error between the two vibration *** modeling is conducted to explore the static and dynamic characteristics of the *** reveal a good agreement with the finite element simulation result.A series of experiments were conducted to assess the static and dynamic performances of the flexible stage,encompassing tests such as amplitude response,motion trajectory,and coupling *** results of these tests revealed that the designed vibration-assisted system exhibits precise movement capabilities.

关键词： Vibration-assisted machining Micromilling Symmetrically decoupling structure Flexible stage

Investigation into the room temperature creep-deformation of potassium dihydrogen phosphate crystals using nanoindentation

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Advances in Manufacturing 2018年第4期6卷 376-383页

作者： Yong Zhang Ning hou Liang-Chi Zhang school of Mechatronics Engineering The Harbin Institute of Technology Harbin 150001 People's Republic of China Ministry of Education Key Laboratory of Micro-systems and Micro-structures Manufacturing The Harbin Institute of Technology Harbin 150001 People's Republic of China Laboratory for Precision and Nano Processing Tech no logies. school of Mechanical and Manufacturing Engineering The University of New South Wales Sydney NSW 2052 Australia

It has been a tremendous challenge to manu facture damage-free and smooth surfaces of potassium dihydrogen phosphate (KDP) crystals to meet the require ments of high-energy laser systems. The intrinsic issue is whether a KDP crystal can be plastically deformed so that the material can be removed in a ductile mode during the machining of KDP. This study investigates the room tem perature creep-deformation of KDP crystals with the aid of nanoindentation. A stress analysis was carried out to identify the creep mechanism. The results showed that KDP crystals could be plastically deformed at the nanoscale. Dislocation motion is responsible for creep-deformation. Both creep rate and creep depth decrease with decrease in peak force and loading rate. Dislocation nucleation and propagation bring about pop-ins in the load displacement curves during nanoindentation.

关键词： Potassium dihydrogen phosphate (KDP) crystals Creep-deformation Stress Dislocation

CaO_(2./Fe^(2.)协同控制污水管道硫化物的效能

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中国环境科学 2024年第10期44卷 5649-5657页

作者：张志强刘雨欣孙逸帆赵磊任晓卫杨静宋姗姗任亚婷卢金锁西安建筑科技大学环境与市政工程学院陕西西安710055 哈尔滨工业大学城市水资源与水环境国家重点实验室黑龙江哈尔滨150090

针对污水管道硫化物的生成和积累导致管道腐蚀、臭味逸散问题,提出CaO_(2./Fe^(2.)协同控制方法.研究了不同CaO_(2.和Fe^(2.)投加量条件下硫化物氧化动力学和作用机制,分析了pH值、温度、无机离子对硫化物氧化去除效能的影响,通过连续... 详细信息

针对污水管道硫化物的生成和积累导致管道腐蚀、臭味逸散问题,提出CaO_(2./Fe^(2.)协同控制方法.研究了不同CaO_(2.和Fe^(2.)投加量条件下硫化物氧化动力学和作用机制,分析了pH值、温度、无机离子对硫化物氧化去除效能的影响,通过连续流反应评估了CaO_(2./Fe^(2.)协同控制方法对污水管道硫化物控制效能.结果表明CaO_(2./Fe^(2.)协同氧化去除硫化物符合伪一级反应动力学,反应过程中生成的HO·是氧化硫化物的主要活性物种,当CaO_(2.和Fe^(2.)物质的量比为4:1时,氧化速率最优;硫化物氧化速率与pH值呈现负相关,与温度呈现正相关,水中常见阴离子和铵离子对氧化速率无显著影响;CaO_(2./Fe^(2.)协同投加可有效控制硫化物生成,当药剂投加量与污水比例(W/V)为0.30%时,硫化物50%生成率恢复周期达8.34d.

关键词：管道腐蚀恶臭气体协同效应反应动力学控制效能

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Mesozoic-Cenozoic extension of the Bohai Sea： contribution to the destruction of North china Craton

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Frontiers of Earth Science 2014年第2期8卷 202-215页

作者： Guiting hou K. R. HARI The Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space Sciences Peking University Beijing 100871 China school of Studies in Geology and Water Resource Management Pt. Ravishankar Shukla University Raipur 492010 India

The Bohai Sea is a Late Mesozoic-Cenozoic feature of the basin-mountain system located in eastern North china Craton （NCC）. The Late Mesozoic thinning of the lithosphere signals the early destruction of the NCC. The onset of the destruction was due to the delamination of thick lithosphere of the craton, represented by the NW- trending grabens in an en-echelon arrangement west to Tanlu Fault, and by the NNE-trending grabens within the Tanlu Fault Zone. The Late Mesozoic NW-trending grabens are overprinted by structures related to the Cenozoic NE-trending pull-apart basin with very thick Mesozoic-Cenozoic sediments in the eastern NCC. C- frequency diagrams of growth faults and the extension factor （fl） of four sections across the basin suggest that the extension migrated from the margin to the center of Bohai Sea, and that the Mesozoic and Cenozoic extension factors for Bohai Sea are higher than that of the margin. These evidences suggest that the greatest extension occurred in the center of Bohai Sea, which is consistent with the thinnest crust being found in the center of the sea. The extension ratios and tectonic evolution of the Bohai Sea suggest that it is the key region for the destruction of the NCC, as evidenced by the topography. However, the NCC experienced two stages of destruction with the late stage related to the tectonic regime of Northeast Asia.

关键词： Bohai Sea extension pull-apart lithosphericthinning destruction of craton

肝门部巨大胆管癌伴发高胆红素血症肝动脉置管化疗术联合靶向治疗获得疾病稳定1例

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中华肝脏病杂志 2024年第9期32卷 845-849页

作者：吴博阳任志忠刘影杨晓伟张跃伟清华大学附属北京清华长庚医院肝胆胰中心北京100034 清华大学医学院北京100034

1例51岁女性患者,患肝门部巨大胆管癌,以黄疸为主要起病表现,在外院经靶向/免疫/化疗治疗后疾病进展,入院后经多学科诊疗讨论,根据基因检测结果,给予了经皮经肝胆管引流术(PTBD)+mFOLFOX-肝动脉置管化疗术(HAIC)+靶向(艾伏尼布)治疗的... 详细信息

1例51岁女性患者,患肝门部巨大胆管癌,以黄疸为主要起病表现,在外院经靶向/免疫/化疗治疗后疾病进展,入院后经多学科诊疗讨论,根据基因检测结果,给予了经皮经肝胆管引流术(PTBD)+mFOLFOX-肝动脉置管化疗术(HAIC)+靶向(艾伏尼布)治疗的方案。治疗期间患者肿瘤大小稳定、胆红素水平稳定,总生存期达到了2.个月。这提示基因检测对胆管癌精准化、个体化诊疗有重要意义,以及mFOLFOX-HAIC联合应用靶向药物治疗方案在伴高胆红素血症的肝胆肿瘤患者中具有有效性和安全性。

关键词：胆管癌靶向治疗肝动脉置管化疗术多学科诊疗治疗

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镁合金板材弯曲回弹预测与控制研究进展

材料导报 2024年第15期38卷 70-76页

作者：计鸿鑫任伟杰蒋先贤杜文宇孙静娜黄华贵国家冷轧板带装备及工艺工程技术研究中心河北秦皇岛066004 燕山大学机械工程学院河北秦皇岛066004

镁合金是最轻的工程金属材料,在新能源汽车、航空航天等领域具有广阔的应用前景,而在这些领域中广泛存在弯曲变形。但镁合金弹性模量较低,室温弯曲成形回弹量大且不易控制,严重影响构件成形精度和后期服役性能,精确预测和控制镁合金回... 详细信息

镁合金是最轻的工程金属材料,在新能源汽车、航空航天等领域具有广阔的应用前景,而在这些领域中广泛存在弯曲变形。但镁合金弹性模量较低,室温弯曲成形回弹量大且不易控制,严重影响构件成形精度和后期服役性能,精确预测和控制镁合金回弹仍是目前亟待解决的重要问题。近年来,为了提高镁合金的成形精度,并扩大其工业化应用,各国学者针对镁合金板材弯曲回弹预测及控制方法进行了大量研究。本文综述了镁板弯曲回弹预测与控制的最新研究进展,介绍了常见的镁合金回弹预测手段,对比分析了镁合金回弹的影响因素与控制方法,最后对镁板弯曲回弹未来研究重点进行了展望。

关键词：镁合金弯曲回弹预测控制

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Enhanced robustness of zero-line modes in graphene via magnetic field

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Frontiers of physics 2019年第2期14卷 53-58页

作者： Ke Wang Tao hou Yafei ren Zhenhua Qiao ICQD Hefei National Laboratory for Physical Sciences at Microscaleand Synergetic Innovation Centre of Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics and Department of Physics University of Science and Technology of ChinaHefei 230026China

We systematically studied the influence of magnetic field on zero-line modes (ZLMs) in graphene and demonstrated the physical origin of their enhanced robustness by employing noneqnilibrium Green's functions and the Landauer Biittiker formula. We found that a perpendicular magnetic field can separate the wavefunctions of the counter-propagating kink states into opposite directions. Specifically, the separation vanishes at the charge neutrality point and increases as the Fermi level deviates from the charge neutrality point and can reach a magnitude comparable to the wavefunction spread at a moderate field strength. Such spatial separation of oppositely propagating ZLMs effectively suppresses backseattering and is more significant under zigzag boundary condition thail under armchair boundary condition. Moreover, the presence of magnetic field enlarges the bulk gap and suppresses the bound states, thereby further reducing the scattering. These mechanisms effectively increase the mean free paths of the ZLMs to approximately 1 |ini in the presence of a disorder.

关键词： graphene topological state zero-line state electronic transport

矩形边界限定形式的感应电机低开关频率预测控制研究

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中国电机工程学报 2024年第8期44卷 3278-3286,I0029页

作者：齐昕张家宁 HOLTZ Joachim 田柏轩任佳仕王辰宇周珂北京科技大学机械工程学院北京市海淀区100083 伍珀塔尔大学电机与驱动实验室德国伍伯塔尔42119 北京科技大学顺德研究生院广东省佛山市528399 北京科技大学高等工程师学院北京市海淀区100083

圆形边界限定形式预测控制对电流畸变的限定在各方向均相同,无法通过增大边界圆半径进一步降低开关频率。因此,该文提出一种矩形边界限定形式的预测控制方法。首先,深入分析感应电机数学模型,发现感应电机转子子系统的低通物理特性,以... 详细信息

圆形边界限定形式预测控制对电流畸变的限定在各方向均相同,无法通过增大边界圆半径进一步降低开关频率。因此,该文提出一种矩形边界限定形式的预测控制方法。首先,深入分析感应电机数学模型,发现感应电机转子子系统的低通物理特性,以及励磁电流波动对电磁转矩的影响不显著;其次,利用该特性,将限定边界改为矩形,对转矩电流与励磁电流进行独立约束,适度增加励磁电流畸变允许限值,扩大电流轨迹运动范围,延长开关状态切换时长;再次,探究电流矢量梯度同边界约束间的数学关系,提出该方法下电压矢量筛选与寻优准则,筛选出最优矢量;最终,进行实验对比。实验结果证明,在相同系统动态特性和转矩波动下,相较于圆形边界限定策略,矩形边界限定策略可以进一步降低开关频率。

关键词：矩形边界低开关频率预测控制感应电机

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Numerical Simulations of Nonlinear Dynamics of Electron Cyclotron Maser with a Straight Beam

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Chinese Physics Letters 2011年第11期28卷 222-223页

作者： KONG Ling-Bao hou Zhi-Ling school of Science Beijing University of Chemical TechnologyBeijing 100029

An electron cyclotron maser based on anomalous Doppler effect(ADECM)with an initially axial beam velocity is considered,and the nonlinear equation of beam-wave interaction is *** the numerical methods,the nonlinear dynamics of the ADECM is *** is shown that the saturated interaction efficiency of the ADECM approaches 90%and the interaction length for the saturated efficiency spans about 5–2. *** results may be of importance for designing a compact device in applications in microwave generations or microwave heating of ceramic laminates.

关键词： microwave saturated beam