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Micro Electrical Discharge Machining Deposition in Air for Fabrication of Micro Spiral Structures

Chinese Journal of Mechanical Engineering 2010年第2期23卷 154-160页

作者： PENG Zilong CHI Guanxin wang zhenlong Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of Technology Harbin 150001 China School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Micro electrical discharge machining（EDM） deposition process is a new micro machining method for fabrication of metal micro structures. In this process, the high level of tool electrode wear is used to achieve the metal material deposition. Up to now, the studies of micro EDM deposition process focused mainly on the researches of deposition process, namely the effects of discharge parameters in deposition process on the deposition rate or deposition quality. The research of the formation of micro structures with different discharge energy density still lacks. With proper conditions and only by the z-axis feeding in vertical direction, a novel shape of micro spiral structure can be deposited, with 0.11 mm in wire diameter, 0.20 mm in outside diameter, and 3.78 mm in height. Then some new deposition strategies including angular deposition and against the gravity deposition were also successful. In order to find the forming mechanism of the spiral structures, the numerical simulation of the transient temperature distribution on the discharge point was conducted by using the finite-element method（FEM）. The results show that there are two major factors lead to the forming of the spiral structures. One is the different material removal form of tool electrode according with the discharge energy density, the other is the influenced degree of the movement of the removed material particles in the discharge gap. The more the energy density in single discharge is, the smaller the mass of the removed material particles is, and the easier the movements of which will be changed to form an order tendency. The fine texture characteristics of the deposited micro spiral structures were analyzed by the energy spectrum analysis and the metallographic analysis. It shows that the components of the deposited material are almost the same as those of the tool electrode. Moreover the deposited material has the brass metallic luster in the longitudinal profile and has compact bonding with the

关键词： micro electrical discharge machining deposition micro spiral structure forming mechanism fine texture analysis

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High-efficiency Approach for Fabricating MTE Rotor by Micro-EDM and Micro-extrusion

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Chinese Journal of Mechanical Engineering 2014年第4期27卷 830-835页

作者： GENG Xuesong CHI Guanxin wang Yukui wang zhenlong School of Mechanical Engineering Harbin Institute of Technology Key Laboratory of Micro-systems and Micro-structures Manufacturing Ministry of EducationHarbin Institute of Technology

Micro-gas turbine engine（MTE） rotor is an important indicator of its property, therefore, the manufacturing technology of the microminiature rotor has become a hot area of research at home and abroad. At present, the main manufacturing technologies of the MTE rotor are directed forming fabrication technologies. However, these technologies have a series of problems, such as complex processing technology high manufacturing cost, and low processing efficiency, and so on. This paper takes advantage of micro electric discharge machining（micro-EDM） in the field of microminiature molds manufacturing, organizes many processing technologies of micro-EDM reasonably to improve processing accuracy, presents an integrated micro-EDM technology and its process flow to fabricate MTE rotor die, and conducts a series of experiments to verify efficiency of this integrated micro-EDM. The experiments results show that the MTE rotor die has sharp outline and ensure the good consistency of MTE rotor blades. Meanwhile, the MTE rotor die is applied to micro extrusion equipment, and technologies of micro-EDM and micro forming machining are combined based on the idea of the molds manufacturing, so the MTE rotor with higher aspect ratio and better consistency of blades can be manufactured efficiently. This research presents an integrated micro-EDM technology and its process flow, which promotes the practical process of MTE effectively.

关键词： integrated micro-EDM micro extrusion MTE rotor efficiency consistency

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Behavioral and physiological responses of striped field mice (Apodemus agrarius) to predator odor

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Integrative Zoology 2011年第4期6卷 334-340页

作者： zhenlong wang Baishi wang Jiqi LU Department of Bioengineering Zhengzhou UniversityZhengzhouChina

Predation risk is one of the most important selective forces in nature and has significant effects on the behavior and physiology of prey *** species have evolved several different traits to reduce and avoid this predation *** research aimed to determine the behavioral and physiological responses of striped field mice to predator *** the present study,we compared the agonistic behavior in male and female striped field mice(Apodemus agrarius Pallas,1771)of the same sexes under the odor derived from a male Himalayan weasel(Mustela sibirica).Dyads were subjected to 5 min staged encounters in neutral arenas once a week for 3 weeks during which agonistic and social behaviors were recorded and fecal hormone concentrations were determined using pre-column derivatization and high performance liquid chromatography ***,we also tested the effects of weasel odor on the adrenal *** results showed that:(i)male striped field mice did not exhibit any change in body weight and physiological characteristics but their aggressive behavior changed over time,and(ii)females responded to predation risk by significantly decreasing body mass and through increases in fecal cortisol levels and adrenal gland *** data show significant sex differences in the body weight,adrenal gland indices and fecal cortisol levels of striped field mouse under predation risk.

关键词： attack behavior cortisol predator odor striped field mouse(Apodemus agrarius)

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A Prototype of a Biomimetic Mantle Jet Propeller Inspired by Cuttlefish Actuated by SMA Wires and a Theoretical Model for Its Jet Thrust

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Journal of Bionic Engineering 2014年第3期11卷 412-422页

作者： Fei Gao zhenlong wang Yukui wang Yangwei wang Jian Li State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 Heilongjiang P. R. China

The cuttlefish have higher swimming speed and more maneuverability than most of the fish mainly benefiting from their unique jet propulsion mechanism, which is realized by the contraction and expansion of their flexible mantle. However it is difficult to mimic this jet propulsion mechanism using conventional electro-mechanical structures. In this paper, the musculature of the cuttlefish mantle and how the mantle flexibly contracts and expands were analyzed first. Then the Shape Memory Alloy（SMA） wires were chosen as the actuators and the soft silica gel was chosen as the body materials to develop a biomimetic mantle jet propeller. The SMA wires were embedded within the soft silica gel formed with cuttlefish mantle shape along the annular direction to mimic the circular muscles of cuttlefish mantle. The water was squeezed out the mantle cavity to form rear jets when the biomimetic mantle was contracted by SMA wires. A mechanical model and a thermal model were established to analyze the jet thrust and the jetting frequency. Theoretical analysis shows that the jet thrust is proportional to the square of the rate of change of SMA strain. Increasing the driving voltage can improve the rate of change of SMA strain, thus can improve both the jet thrust and the jetting frequency. However the j etting frequency is mainly restricted by the cooling of SMA wires. To maximize the jetting frequency, the optimal driving parameters for different driving voltage were calculated. The propulsion performance was tested and the results show that the jet thrust can increase with the driving voltage as predicted and the maximum average jet thrust is 0.14 N when the driving voltage is 25 V. The swimming test was carried out to verify the feasibility of the novel design. It is shown that the biomimetic jet propeller can swim with higher speed as the jet thrust and jetting frequency increase and the maximum speed can reach 8.76 cm·s^-1 （0.35 BL·s^-1） at a jetting frequency of 0.83 Hz.

关键词： cuttlefish biomimetic jet thrust shape memory alloy

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Electrode design using revolving entity extraction for high-efficiency electric discharge machining of integral shrouded blisk

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Chinese Journal of Aeronautics 2021年第6期34卷 178-187页

作者： Yuchao JIA Guanxin CHI Yang SHEN Kun ZHANG zhenlong wang Yukui wang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Capital Aerospace Machinery Company China Academy of Launch Vehicle TechnologyBeijing 100076China

The integral shrouded blisk provides better performance with minimum weight,but its semi-open structure presents problems for its *** processes of these components require a removal of about 70%-90%of material from their ***-axis electrical discharge machining(EDM)is commonly used for these processes,but its poor efficiency cannot meet the requirements of mass *** flushing assisted high-current discharge is able to improve the machining *** this paper,this method was applied to manufacture the integral shrouded *** electrode design method was *** the largest revolving entity inside the flow channel as the base geometry,this laminated arc-shaped hollow electrode meets the requirements such as high pressure flushing,tool wear compensation,and easy to be made.A 4-axis linkage machining tool path with planetary motion was *** an integral guide vane ring as an example,it has been experimentally verified that the time consumption for each channel using this method was reduced to a half of the ordinary EDM method,while the finished surface quality remains same.

关键词： EDM Electrode High efficiency Trajectory Turbine blades

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Effects of social and climatic factors on birth sex ratio in Macaca mulatta in Mount Taihangshan area

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Integrative Zoology 2015年第2期10卷 199-206页

作者： Jundong TIAN Baishi wang zhenlong wang Jindong LIU Jiqi LU Institute of Biodiversity and Ecology Zhengzhou UniversityZhengzhouChina Jiyuan Administration of Taihangshan Macaque National Nature Reserve JiyuanChina Department of Wildlife Diseases Leibniz Institute for Zoo and Wildlife ResearchBerlinGermany

Sex allocation theory predicts the optimal investment to male and female ***,a biased sex ratio requires explanations as to why the deviation *** macaque(Macaca mulatta)is the most widely distributed nonhuman primate species and the Taihangshan macaque(Macaca mulatta tcheliensis)occupies the northern limit of all rhesus macaque natural populations *** observed one macaque troop(wangwu-1[WW-1])inhabiting Taihangshan Macaque National Nature Reserve and recorded all birth events and the sex of newborn macaques from 2004 to *** aim was to apply the Trivers–Willard hypothesis to this free-ranging rhesus macaque troop,and to understand the relationship between climatic parameters(precipitation and temperature)and birth sex *** found that the total newborn macaques showed a female-biased sex ratio at birth in the WW-1 troop,but there were no significant biased birth sex ratios in all matriarchs and in high-ranking and middle-ranking matrilineal ***,the low-ranking macaque matrilineal unit was significantly ***,we found that the annual precipitation of the previous year was positively associated with the birth sex ratio,and there was an interactive effect of troop size and current winter temperature on the birth sex *** underlying mechanisms for the effects of social and climatic factors on birth sex ratio could be complex,and we discuss several plausible explanations.

关键词： birth sex ratio precipitation rhesus macaque social rank Trivers-Willard hypothesis

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MICRO ELECTRICAL DISCHARGE MACHINING DEPOSITION IN AIR

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 622-625页

作者： JIN Baidong ZHAO Wansheng wang zhenlong CAO Guohui School of Mechanical Engineering Harbin Institute of Technology Harbin 150001 China

A new deposition method is described using micro electrical discharge machining （EDM） to deposit tool electrode material on workpiece in air. The basic principles of micro electrical discharge deposition （EDD） are analyzed and the realized conditions are predicted. With an ordinary EDM shaping machine, brass as the electrode, high-speed steel as the workpiece, a lot of experiments are carried out on micro EDD systematically and thoroughly. The effects of major processing parameters, such as the discharge current, discharge duration, pulse interval and working medium, are obtained, As a result, a micro cylinder with 0.19 mm in diameter and 7.35 mm in height is deposited. By exchanging the polarities of the electrode and workpiece the micro cylinder can be removed selectively. So the reversible machining of deposition and removal is achieved, which breaks through the constraint of traditional EDM. Measurements show that the deposited material is compact and close to workpiece base, whose components depend on the tool electrode, material.

关键词： Electrical discharge machining(EDlVD Electrical discharge deposition(EDD) Reversible machining Processing pararneters

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Antioxidant response to severe hypoxia in Brandt’s vole Lasiopodomys brandtii

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Integrative Zoology 2022年第4期17卷 581-595页

作者： Luye SHI Bojian CHEN Xinrui wang Maolin HUANG Congcong QIAO Jingou wang zhenlong wang School of Life Sciences Zhengzhou UniversityZhengzhouChina State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingChina College of Environmental Science and Engineering Tongji UniversityShanghaiChina Jiaxing-Tongji Environmental Research Institute JiaxingChina Centre for Nutritional Ecology Zhengzhou UniversityZhengzhouChina

The antioxidant defense system is essential for animals to cope with homeostasis disruption and overcome oxidative stress caused by adverse environmental conditions such as ***,our understanding of how this system works in subterranean rodents remains *** this study,Brandt’s vole Lasiopodomys brandtii was exposed to normoxia(21%O_(2))or hypoxia(mild or severe hypoxia:10%or 5%O_(2))for 6 *** in key enzymes of the classic enzymatic antioxidant system at both mRNA and enzyme activity levels,and tissue antioxidant levels of the low-molecular-weight antioxidant system were determined in brain,liver,and *** levels of the upstream regulator NF-E2-related factor 2(Nrf2)were also *** found that the mRNA expression of Nrf2 and its downstream antioxidant enzyme genes in *** were relatively conserved in response to hypoxia in most tissues and genes tested,except in the *** Nrf2,Cu/Zn SOD,GPx1,and GPx3 levels were significantly upregulated in response to mild hypoxia,whereas Mn SOD level decreased significantly in severe *** with changes at the RNA level,constitutively high and relatively stable antioxidant enzyme activities were maintained *** the low-molecular-weight antioxidant system,an abrupt increase of cerebral ascorbic acid(AA)levels in hypoxia indicated a tissue-specific antioxidant *** hypoxia did not cause significant oxidative damage in most tissues tested,the significant decrease in antioxidant enzyme activities(GPX and GR)and increase in lipid peroxidation in the kidney suggest that prolonged hypoxia may pose a critical threat to this species.

关键词： climate change Nrf2 oxidative stress oxygen fluctuation subterranean rodent

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Stratum Griseum Periventriculare-mediated Fear Emotion Regulates Motor Behavior in Pigeons

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Journal of Bionic Engineering 2023年第5期20卷 2228-2239页

作者： Wenbo Xu Long Yang Zishi wang Lifang Yang Han Cheng Shixin Zhu Zhigang Shang zhenlong wang School of Life Sciences Zhengzhou UniversityZhengzhou450001China School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou450001China

A pigeon robot is an ideal experimental animal for research in flying animal *** majority of current research publications have entailed electrical stimulation of the motor nuclei to regulate movement forcibly,and although a“virtual fear”behavior model has been proposed,the structure,location,and function of the nuclei that generate fear emotions remain *** studies have shown that the Stratum Griseum Periventriculare(SGP)of pigeons is homologous to the mammalian periaqueductal gray(PAG),which plays an essential role in mammalian *** reveal the role of fear mediated by the SGP in behavioral regulation,we evaluated the structure and location of the SGP by histologic identification combined with magnetic resonance imaging,and analyzed the behavior of the SGP by electrical ***,the function of the SGP was verified with escape testing and homing experiments in an open *** results showed that the SGP is located in the pigeon midbrain and divided into two subregions,the dorsal part of the stratum griseum periventriculare(SGPd)and the ventral part of the stratum griseum periventriculare(SGPv)(the ranges were AP1.5–4.75 mm,ML1.75–6.75 mm,and DV2.2–7.1 mm),and that wired and wireless electrical stimulation freezing was the dominant *** the escape test,SGP electrical stimulation caused the pigeons to flee to a safe place,while in the open-field homing test,electrical stimulation of the SGP induced evasive behavior in pigeons away from their original homing *** results confirm that the SGP plays a crucial role in fear,and that electrical stimulation of this nucleus induces corresponding fear behaviors.

关键词： Pigeon cyborg Bionic robot Fear Freezing Electrical stimulation

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Complex spatial patterns delay the discovery and location of food by rodents

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Integrative Zoology 2020年第4期15卷 307-313页

作者： Shiqiang ZHANG Meilin ZHU Huixia ZHANG Nannan YAO Yingying wang Yifeng ZHANG zhenlong wang School of Life Sciences Zhengzhou UniversityGaoxin DistrictZhengzhouHenan ProvinceChina College of Basic Medical Sciences Zhengzhou UniversityGaoxin DistrictZhengzhouHenan ProvinceChina State-owned Yugong Forest Farm JiyuanHenan ProvinceChina

Spatial patterns in heterogeneity are generally deemed a central causal factor influencing the physiology and behavior of animals in ecological ***,knowledge remains limited about how such patterns influence food discovery by *** inferred that spatial heterogeneity plays a key role in animal food discovery and *** prove this inference,we tested food locating parameters by 2 rodent species,Apodemus agrarius and Lasiopodomys brandtii,in different heterogeneous *** results showed that spatial heterogeneity significantly influenced the food locating time of rodents,with food locating time increasing with increasing spatial ***,spatial heterogeneity significantly influenced invalid excavations(digging in the wrong place).Finally,spatial heterogeneity significantly influenced the frequency that heterogeneous objects were *** our inference,our results indicate that spatial heterogeneity significantly influences the foraging behavior of ***,increased spatial heterogeneity will impair the food locating success of *** believe that this work will broaden our understanding of plant–animal interactions.

关键词： food locating invalid excavation rodents spatial heterogeneity

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