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Development of a monocular vision system for robotic drilling

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 593-606页

作者： Wei-dong ZHU Biao mei Guo-rui YAN Ying-lin KE Department of Mechanical Engineering Zhejiang University The State Key Lab of Fluid Power Transmission and Control Zhejiang University

Robotic drilling for aerospace structures demands a high positioning accuracy of the robot, which is usually achieved through error measurement and compensation. In this paper, we report the development of a practical monocular vision system for measurement of the relative error between the drill tool center point(TCP) and the reference hole. First, the principle of relative error measurement with the vision system is explained, followed by a detailed discussion on the hardware components, software components, and system integration. The elliptical contour extraction algorithm is presented for accurate and robust reference hole detection. System calibration is of key importance to the measurement accuracy of a vision system. A new method is proposed for the simultaneous calibration of camera internal parameters and hand-eye relationship with a dedicated calibration board. Extensive measurement experiments have been performed on a robotic drilling system. Experimental results show that the measurement accuracy of the developed vision system is higher than 0.15 mm, which meets the requirement of robotic drilling for aircraft structures.

关键词： Vision system Robotic drilling Error measurement Elliptical contour extraction Hand-eye calibration

Effect of welding speed on microstructure and mechanical properties of laser-welded transformation induced plasticity(TRIP)steels

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Journal of Iron and Steel Research International 2020年第9期27卷 1087-1098页

作者： Tao Wang mei Zhang Ren-dong Liu Liang Zhang lin Lu Wen-heng Wu Shanghai Research Institute of Materials Shanghai Engineering Research Center of 3D Printing MaterialsShanghai 200437China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China State Key Laboratory of Advanced Special Steels Shanghai UniversityShanghai 200072China Technique Center of Ansteel Ansteel Group CorporationAnshan 114001LiaoningChina

The weldability of 0.28C-2.0Mn-0.93Al-0.97Si(wt.%)transformation induced plasticity(TRIP)steels was investigated using a 2.5 kW CO2 laser at the welding speeds of 2,2.5 and 3 m/*** welded joints were characterized in terms of hardness,tensile properties and ***-quality welded joints of TRIP steels with the carbon equivalent of 0.7 were *** loss of ductility,nearly unvaried hardness of the fusion zone(FZ)and tensile strength equal to the base metal were observed with increasing welding *** martensite and lower bainite formed in FZ and the microstructure of FZ varied little with welding *** thermal simulations of heat-afected zone(HAZ)were carried out using a quenching dilatometer,and the microstructures of dilatometric samples revealed the carbon diffusion-controlled transformations in *** microstructure distribution of HAZ could be influenced by the welding speed due to the significant temperature gradient over the narrow HAZ.

关键词： Laser welding Welding speed Transformation induced plasticity steel Tensile property Weld thermal simulation Microstructural evolution

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剖宫产率的变迁与产后出血的关系

新疆医科大学学报 2001年第1期24卷 32-34页

作者：王冬梅腊晓琳朱启英新疆医科大学第一附属医院产科新疆乌鲁木齐830054

目的 :探讨剖宫产率的上升对产后出血的影响。方法 :对 1995年 1月～ 1998年 12月在我院分娩的 630 8例产妇进行回顾性分析。统计分析剖宫产率的变迁和产后出血的关系 ,以及不同分娩方式对产后出血的影响 ,分析造成产后出血的原因。结... 详细信息

目的 :探讨剖宫产率的上升对产后出血的影响。方法 :对 1995年 1月～ 1998年 12月在我院分娩的 630 8例产妇进行回顾性分析。统计分析剖宫产率的变迁和产后出血的关系 ,以及不同分娩方式对产后出血的影响 ,分析造成产后出血的原因。结果 :剖宫产率和产后出血率均呈逐年上升的趋势 ,在不同分娩方式中 ,产后出血的发生率以剖宫产组最高。结论 :严格掌握剖宫产指征。

关键词：产后出血剖宫产相互关系剖宫产率手术指征

Engineering of Fe d-band center in Fe_(3)O_(4)/CeO_(2)hetero-nanoparticles via orbital coupling for high-efficiency oxygen reduction electrocatalysis

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Nano Research 2025年第1期18卷 129-139页

作者： Jiayi Liu Jingwen Yin Yingzi lin Mingxin Pang Huan Pang Songtao Zhang lin Xu Jun Yang Yawen Tang Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023Chin a 2 State Key Laboratory of Multiphase Complex Systems Center of MesoscienceInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China Testing Center Yangzhou UniversityYangzhou 225009China

The deliberate engineering of the d-band center of metal site represents an effective strategy to boost the intrinsic electrocatalytic performance toward the oxygen reduction reaction(ORR).Herein,following a heterointerfaceinduced orbital coupling rationale,we report a judicious design of an efficient ORR electrocatalyst consisting of Fe_(3)O_(4)/CeO_(2)hetero-nanoparticles in-situ encased into N-doped carbon nanofibers(abbreviated as Fe_(3)O_(4)/CeO_(2)@N-CNFs hereafter).The theoretic calculations uncover that the Fe_(3)O_(4)/CeO_(2)heterointerface-triggered orbital coupling can cause the down shift of the d-band center positions of Fe sites,which leads to the weakened chemisorption of oxygenated groups and lowered energy barrier for the potential-determining step,ultimately dramatically boosting the ORR intrinsic *** a consequence,the well-designed Fe_(3)O_(4)/CeO_(2)@N-CNFs display admirable ORR activity with a half-wave potential of 0.84 V and outstanding structural/electrochemical stability in an alkaline electrolyte,surpassing the commercial Pt/C benchmark and a majority of recently reported Fe_(3)O_(4)-based *** encouragingly,the Fe_(3)O_(4)/CeO_(2)@N-CNFsincorporated Zn-air battery outperforms the Pt/C-assembled counterpart with higher power density,larger energy density,and excellent cycling stability,serving as a competent candidate for ORR-involved renewable energy *** study offers an innovative approach for the rational manipulation of the d-band center and interfacial electron behavior of active sites toward the optimization of electrocatalytic performance.

关键词： hetero-nanoparticles electrospinning interfacial engineering orbital coupling oxygen reduction reaction

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En Zhou Yilin Li Xiaoming lin Jiaye Ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Lithium-ion batteries(LIBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with Li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(LIBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template Lithium-ion batteries Sodium-ion batteries Potassium-ion batteries

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui Peng Peng Wu Zong-lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

彩色多普勒超声评价异位妊娠保守治疗前后血流动力学变化

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四川医学 2009年第7期30卷 1152-1153页

作者：侯莉张冬梅林果叶才为成都市妇幼保健院超声科四川成都610031

目的利用彩色及频谱多普勒显像技术对异位妊娠保守治疗前后的血供进行观察,探讨异位妊娠保守治疗前后的血流动力学变化。方法经阴道彩色多普勒对40例异位妊娠保守治疗术前及术后3d、7d、1个月的血流动力学变化进行检测,并用能量图观察... 详细信息

目的利用彩色及频谱多普勒显像技术对异位妊娠保守治疗前后的血供进行观察,探讨异位妊娠保守治疗前后的血流动力学变化。方法经阴道彩色多普勒对40例异位妊娠保守治疗术前及术后3d、7d、1个月的血流动力学变化进行检测,并用能量图观察血流情况。结果异位妊娠保守治疗前、后3d、7d、1个月比较,40例患者37例保守治疗3d、7d血流量减少,Vm、PI、RI均明显降低,2例血流无明显变化,1例血流量增加。1个月后均未见明显血流显示。P<0.01。结论彩色及频谱多普勒超声是观察异位妊娠保守治疗效果的较好方法。

关键词：彩色多普勒血流显像异位妊娠血流动力学

Nitrobenzene contamination of groundwater in a petrochemical industry site

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Frontiers of Environmental Science & Engineering 2019年第2期13卷 157-164,F0003页

作者： Yongsheng Zhao lin lin mei Hong Key Laboratory of Groundwater Resources and Environment of the Ministry of Education College of New Energy and EnvironmentJilin UniversityChangchun 130012China

Organic contamination of groundwater is a major concern in ***,remediation technology for groundwater contamination to address the potential harm and danger brought by the abovementioned serious issue is still in the research *** study aims to improve the current research *** the research project,drilling,soil,and groundwater sampling and analysis were conducted in a contamination site of a petrochemical plant,migration of contaminants to the river was predicted using a numerical model,the sequence permeable reactive barrier(PRB)for treating nitrobenzene(NB)and benzene was proposed,and simulation was carried *** findings demonstrated that three leaking locations had been identified in the plant,the major pollutants were NB and benzene,and the groundwater contamination area was around 640000 *** results of the numerical model indicated that,in the worst case,the groundwater plume would reach the river after migration for nearly 9 years,which would endanger the safety of surface water ***,the twoPRB system with the filling of zero-valent iron(ZVI)and granular activated carbon attached with biofilm exerted strong remediation *** results indicated that ZVI could transform NB to aniline effectively with a rate of approximately 93%.Meanwhile,aniline,benzene,and other organic pollutants could easily be biodegraded.

关键词： Nitrobenzene Benzene Groundwater Zero-valent iron Permeable reactive barrier

Selective dissolution of eodiagenesis cements and its impact on the quality evolution of reservoirs in the Xing＇anling Group,Suderte Oil Field, Hailar Basin, China

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Petroleum Science 2016年第3期13卷 402-417页

作者： Zhen-Zhen Jia Cheng-Yan lin Li-Hua Ren Chun-mei dong School of Geosciences China University of Petroleum Qingdao 266580 Shandong China Key Laboratory of Reservoir Geology in Shandong Province Qingdao 266580 Shandong China

Reservoirs in the Xing＇anling Group in the Suderte Oil Field,Hailar Basin exhibit ultra-low to low permeability and high tuffaceous material *** study comprehensively analyzed diagenesis and quality evolution of these low-permeability reservoirs using thin sections,SEM samples,rock physical properties,pore water data,as well as geochemical numerical *** and analcite are the two main types of cements precipitated in the eodiagenetic stage at shallow burial depths in the *** two cements occupied significant primary intergranular pores and effectively retarded deep burial *** textures suggest selective dissolution of massive analcite and little dissolution of calcite in the mesodiagenetic *** calculations utilizing the Geochemist＇s Workbench 9.0indicated that the equilibrium constant of the calcite leaching reaction is significantly smaller than that of the analcite leaching reaction,resulting in extensive dissolution of analcite rather than calcite in the geochemical system with both minerals *** simulations with constraints of kinetics and pore water chemistry demonstrated that the pore water in the Xing＇anling group is saturated with respect to calcite,but undersaturated with analcite,leading to dissolution of large amounts of analcite and no dissolution of *** secondary intergranular pores have formed in analcite-cemented reservoirs from selective dissolution of analcite in the mesodiagenetic stage;the analcite dissolution formed preferential flow paths in the reservoirs,which promoted feldspar dissolution;and dissolution of such minerals led to the present reservoirs with medium porosity and low ***-cemented tight reservoirs have not experienced extensive dissolution of cements,so they exhibit ultra-low porosity and permeability.

关键词： Eodiagenetic cements Calcite Analcite Selective dissolution Secondary porosity Hailar Basin