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Progress on Bionic Textured Cutting Tools:A Review and Prospects

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Journal of Bionic Engineering 2024年第1期21卷 19-55页

作者： Hong Wei Guangjun Chen Zhuang Chen zhiwei yu Jiashuai Huang Tianjin Key Laboratory of High Speed Cutting and Precision Processing Tianjin 300222China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

Cutting tools are known as the“productivity”of the manufacturing industry,which affects the production efficiency and quality of the workpiece,and has become the focus of research and attention in academia and industry.However,traditional cutting tools often suffer from adhesion or wear during the cutting process,which considerably reduces the cutting efficiency and service life of the tools,and makes it difficult to meet current production requirements.To solve the above problems,scholars have introduced bionics into the tool’s design,applying the microscopic structure of the biological surface to the tool surface to alleviate the tool’s failure.This paper mainly summarizes the research progress of bionic textured cutting tools.Firstly,categorize whether the bionic texture design is inspired by a single organism or multiple organisms.Secondly,it is discussed that the non-smooth surface of the biological surface has five characteristics:hydrophilic lubricity,wear resistance,drag reduction and hydrophobicity,anti-adhesion,and arrangement,and the non-smooth structure of these different characteristics are applied to the surface of the tool is designed with bionic texture.Furtherly,the cutting performance of bionic textured cutting tools is discussed.The anti-friction and wear-resisting mechanism of bionic textured cutting tools is analyzed.Finally,some pending problems and perspectives have been proposed to provide new inspirations for the design of bionic textured cutting tools.

关键词： Bionic textured cutting tools Biological microstructure characteristics Cutting performance Anti-friction and wear-resisting mechanism

Intermittent failure mechanism and stabilization of microscale electrical contact

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Friction 2023年第4期11卷 538-545页

作者： Tianbao MA zhiwei yu Aisheng SONG Jiahao ZHAO Haibo ZHANG Hongliang LU Dandan HAN Xueyan WANG Wenzhong WANG State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Inspur Beijing Electronic Information Industry Co. Ltd.Beijing 100085China Department of Precision Instrument Tsinghua UniversityBeijing 100084China Innovation Center for Future Chips Beijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Beijing 100084China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The stability and lifetime of electrical contact pose a major challenge to the performance of microelectro-mechanical systems(MEMS),such as MEMS switches.The microscopic failure mechanism of electrical contact still remains largely unclear.Here conductive atomic force microscopy with hot switching mode was adopted to simulate the asperity-level contact condition in a MEMS switch.Strong variation and fluctuation of current and adhesion force were observed during 10,000 repetitive cycles,exhibiting an“intermittent failure”characteristic.This fluctuation of electrical contact properties was attributed to insulative carbonaceous contaminants repetitively formed and removed at the contact spot,corresponding to degradation and reestablishment of electrical contact.When contaminant film was formed,the contact interface became“metal/carbonaceous adsorbates/metal”instead of direct metal/metal contact,leading to degradation of the electrical contact state.Furthermore,a system of iridium/graphene on ruthenium(Ir/GrRu)was proposed to avoid direct metal/metal contact,which stabilized the current fluctuation and decreased interfacial adhesion significantly.The existence of graphene enabled less adsorption of carbonaceous contaminants in ambient air and enhanced mechanical protection against the repetitive hot switching actions.This work opens an avenue for design and fabrication of microscale electrical contact system,especially by utilizing two-dimensional materials.

关键词： atomic force microscopy microscale electrical contact graphene

Status of research on non-conventional technology assisted single-point diamond turning

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纳米技术与精密工程(英文) 2023年第3期6卷 79-92页

作者： Zhuang Chen Guangjun Chen zhiwei yu Jiashuai Huang Hong Wei Tianjin Key Laboratory of High Speed Cutting and Precision Processing Tianjin 300222China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

With the increasing use of difficult-to-machine materials in aerospace applications,machining requirements are becoming ever more rigorous.However,traditional single-point diamond turning(SPDT)can cause surface damage and tool wear.Thus,it is difficult for SPDT to meet the processing requirements,and it has significant limitations.Research indicates that supplementing SPDT with unconventional techniques can,importantly,solve problems due to the high cutting forces and poor surface quality for difficult-to-machine materials.This paper first introduces SPDT and reviews research into unconventional techniques for use with SPDT.The machining mechanism is discussed,and the main advantages and disadvantages of various methods are investigated.Second,hybrid SPDT is briefly described,which encompasses ultrasonic-vibration magnetic-field SPDT,ultrasonic-vibration laser SPDT,and ultrasonic-vibration cold-plasma SPDT.Compared with the traditional SPDT method,hybrid SPDT produces a better optical surface quality.The current status of research into unconventional techniques to supplement SPDT is then summarized.Finally,future development trends and the application prospects of unconventional assisted SPDT are discussed.

关键词： Single-point diamond turning Machined surface quality Tool wear Unconventional auxiliary technique

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中国城市植被物候变化及其对地表温度的响应

生态学报 2024年第6期44卷 2479-2494页

作者：缪丽娟余志巍何昱张宇阳南京信息工程大学地理科学学院南京210044

量化植被物候与城市化进程之间的关系对探索人类活动对城市生态系统的影响至关重要。以中国35个城市及周边区域为研究对象,基于中分辨率成像光谱仪(Moderate-resolution Imaging Spectroradiometer,MODIS)提供的归一化植被指数(Normaliz... 详细信息

量化植被物候与城市化进程之间的关系对探索人类活动对城市生态系统的影响至关重要。以中国35个城市及周边区域为研究对象,基于中分辨率成像光谱仪(Moderate-resolution Imaging Spectroradiometer,MODIS)提供的归一化植被指数(Normalized Difference Vegetation Index,NDVI),采用Savitzky-Golay滤波和动态阈值法提取2000—2020年研究区植被返青期(Start of Growing Season,SOS)和枯黄期(End of Growing Season,EOS)。并分析不同城市规模、不同距离城市的植被物候变化对陆地地表温度(Land Surface Temperature,LST)与不透水面(Impervious Surface Area,ISA)的响应差异。研究发现:(1)2000—2020年,中国城市城区植被SOS和EOS分别以0.17d/a和0.15d/a的速率推迟。根据城市规模的不同,大城市和中等城市物候期呈推迟趋势,而超大城市、特大城市和小城市呈提前趋势。51%的城市植被SOS提前,主要分布在中国华北、西北及南部地区,其他地区城市植被SOS推迟(49%),80%的城市植被EOS推迟。空间上看,东部和南部平原地区城市植被SOS比西北部地区早(早于第91天),而EOS则比较晚(晚于第314天),而西部和北部城市植被SOS(晚于第91天)和EOS(早于第314天)呈相反态势;(2)距离城区越近,63%的城市表现为植被SOS提前(0.6—4.3 d/km),60%的城市表现为植被EOS推迟(0.2—1.9 d/km);(3)所有城市春季LST均呈现增长趋势,春季ΔLST每增长1℃,SOS提前6.8 d。秋季ΔLST每增长1℃,EOS推迟1.5 d。城市植被SOS与ISA占比显著负相关,ISA占比增长1%,植被SOS提前0.253 d,植被EOS与ISA占比显著正相关,ISA占比每增长1%,植被EOS推迟0.106 d。此外,不同人口规模的城市植被物候对LST和ISA响应存在差异,大城市和超大城市植被物候对LST和ISA占比的响应比其他城市更为敏感,表明特大城市和大城市在城郊梯度上植被物候期对LST与ISA占比响应更为明显。

关键词： MODIS NDVI 物候变化地表温度不透水面城市化中国城市

Chronology of environmental events over East Asia during the past 130 ka

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Chinese Science Bulletin 1998年第21期43卷 1761-1769页

作者： Zhongli Ding Jimin Sun zhiwei yu Dongsheng Liu Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China China Univ Min Dept Geol Xuzhou 221008 Peoples R China

In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at yuling, Hengshan, Dingbian and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events.

关键词： environmental events time scale Chinese loess.

碘摄入量与甲状腺乳头状癌关系的Meta分析

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中国肿瘤外科杂志 2024年第3期16卷 253-260页

作者：尉志伟徐斐王廷空军军医大学第一附属医院甲乳血管外科陕西西安710032

目的探究碘摄入量与甲状腺乳头状癌(PTC)的相关性。方法根据PICOS制定检索策略,收集Pubmed、Cochrane Library、Web of Science、CNKI和万方数据库中有关碘摄入量与PTC的病例对照研究共12篇参考文献,共计纳入6214名研究对象,进行Meta分... 详细信息

目的探究碘摄入量与甲状腺乳头状癌(PTC)的相关性。方法根据PICOS制定检索策略,收集Pubmed、Cochrane Library、Web of Science、CNKI和万方数据库中有关碘摄入量与PTC的病例对照研究共12篇参考文献,共计纳入6214名研究对象,进行Meta分析。结果碘摄入水平过量与PTC的发生有关(OR=5.66,95%CI:2.25~12.68,P<0.001),而适量的碘摄入则能够降低PTC的发生风险(OR=0.26,95%CI:0.13~0.52,P<0.01)。碘摄入水平过量与PTC包膜外侵犯(ENE)、中央区淋巴结转移(CLNM)、BRAF基因突变等无关。结论碘摄入过量增加PTC发生风险,适量的碘摄入是PTC的保护因素。

关键词：甲状腺乳头状癌碘碘摄入量碘营养尿碘 Meta分析

Optimized Bio-inspired Micro-pillar Dry Adhesive and Its Application for an Unmanned Aerial Vehicle Adhering on and Detaching from a Ceiling

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Journal of Bionic Engineering 2020年第1期17卷 45-54页

作者： Qingsong He Xianrui Xu zhiwei yu Kai Huo Zhaoyang Wang Nuo Chen Xuean Sun Gui Yin Peile Du Yang Li Zhendong Dai Institute of Bio-inspired Structure and Surface Engineering Jiangsu Provincial Key Laboratory of Bionic Functional MaterialsCollege of Mechanical and Electrical EngineeringNanjing University of Aeronautics&AstronauticsNanjing 210016China College of Astronautics Nanjing University of Aeronautics&AstronauticsNanjing 210016China China Ship Development and Design Center Shanghai Branch Shanghai 201108China

Various bio-inspired dry adhesive materials have been investigated.In this work,lithography and silicon deep etching method were used to fabricate bio-inspired micro-pillar dry adhesive materials of which the parameters,such as side length,Height to Side length Aspect Ratio(HSAR),and inter-pillar Distance to Side length Aspect Ratio(DSAR)were comprehensively studied to obtain a dry adhesive with high adhesion.An orthogonal array method was designed and a series of fabrication experiments were conducted to identify optimum parameters,which resulted in a high normal adhesion of 2.98 N·cm^-2 and a shear adhesion of 9.59 N·cm^-2.An adhesion and desorption device was further designed on basis of the optimum dry adhesive,which enables an Unmanned Aerial Vehicle(UAV)to successfully adhere on and detach from a ceiling.This would allow an UAV to stay aloft for prolonged time,which could be invaluable to many applications,such as energy conservation and aerial detection.

关键词： bio-inspired dry adhesive orthogonal array method UAV adhere ceiling

乡村产业数字互联与风貌在地营建——以杨桥村“富竹云驿”为例

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浙江建筑 2024年第1期41卷 51-54页

作者：俞志伟李盈吴艳董志凌中国联合工程有限公司浙江杭州310056

在全面推进共同富裕现代化基本单元建设和数字时代的大背景下,社会面上的信息传递变得愈发重要,通过信息化方式与互联网平台整合乡村资源,加强信息交互是促进乡村产业多元化发展和实现乡村振兴的重要方式之一。在此,以临安区太湖源镇杨... 详细信息

在全面推进共同富裕现代化基本单元建设和数字时代的大背景下,社会面上的信息传递变得愈发重要,通过信息化方式与互联网平台整合乡村资源,加强信息交互是促进乡村产业多元化发展和实现乡村振兴的重要方式之一。在此,以临安区太湖源镇杨桥村风貌驿项目实践为例,通过规划及建筑设计手段,落位云平台,改造提升竹乡风貌,打造信息交互与对外展示窗口,以空间设计回应产业升级,为打造强普适性、强个性共存的共同富裕乡村基本单元示范样本提供参考。

关键词：乡村振兴共富风貌驿建筑设计

Geostatistical Analysis of Soil Nutrients Based on GIS and Geostatistics in the Typical Plain and Hilly-Ground Area of Zhongxiang, Hubei Province

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Open Journal of Soil Science 2013年第5期3卷 218-224页

作者： Yangbo Xu Donglin Dong Guobin Duan Xuetao yu zhiwei yu Wei Huang College of Geoscience and Surveying Engineering China University of Mining & Technology Beijing China College of Resources and Environment Huazhong Agricultural University Wuhan China. State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China College of Geoscience and Surveying Engineering China University of Mining & Technology Beijing China State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China College of Geoscience and Surveying Engineering China University of Mining & Technology Beijing China

Techniques of geostatistics are used to perform traditional statistical analysis and spatial structural analysis with ArcGIS, geostatistical software GS+ and statistical software SPSS in order to obtain the knowledge of characteristics of distribution and spatial variability of soil nutrients in different parts of Zhongxiang, Hubei Province. Some skewed values appeared during the analyses. To decrease the influence of those skewed values, domain processing and Box-Cox transformation were used. The results indicated spatial variability of Total N, Avail. P, rapidly-available potassium (R-Avail. K) and effective zinc (Effect. Zn) was strong, that of organic carbon (Org. C), effective molybdenum (Effect. Mo) and effective copper (Effect. Cu) was medium while that of others was weak. Fitted model of Total N, R-Avail. K and Effect. Mo was spherical model, that of Org. C and Effect. Zn was exponential model, while fitted model of Avail. P and Effect. Cu was Gaussian model. Ratio of variability caused by random factors to overall variability was large. What’s more, the ranges of spatial autocorrelation of soil nutrients had much difference. The smallest value was 3600 m in Effect. Zn while the largest was 77970 m in Org. C. Other characteristics were also included. The study is helpful to soil sampling design, to make people realize the influence of Han River to spatial variability of soil nutrients in this area, and to spatial interpolation and mapping.

关键词： Zhongxiang Soil Nutrients Geostatistical Analysis Geostatistics GIS GS+ SPSS