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Rare Metals 2009年第1期28卷 9-13页

作者： LIU Jinjun LIU Xincai PAN Jing JIANG chengyong State Key Laboratory Base of Novel Functional Materials and Preparation Science Faculty of Materials Science and Chemical Engineering Ningbo University Ningbo 315211 China

The C15 Laves phase with composition Tb0.2Pr0.8（Fe0.4Co0.6）1.93 was synthesized by mechanical alloying （MA） and subsequent annealing process. The structure and magnetic properties of Tb0.2Pr0.8（Fe0.4Co0.6）1.93 were investigated by means of X-ray diffraction （XRD）, a vibrating sample magnetometer, and a standard strain technique. The effect of annealing on the structure and magnetic properties was studied. The analysis of XRD shows that the high Pr-content Tb0.2Pr0.8（Fe0.4Co0.6）1.93 alloy with the single phase of MgCu2-type structure can be successfully synthesized by MA method. The sample annealed at 450℃ is found to have a coercivity of 196 kA/m at room temperature. An epoxy/Tb0.2Pr0.8（Fe0.4Co0.6）1.93 composite was produced by a cold isostatic pressing technique. A large magnetostriction of 400 ppm, at an applied magnetic field of 800 kA/m, was found for the composite. The epoxy-bonded Tb0.2Pr0.8（Fe0.4Co0.6）1.93 composite combines a high magnetostriction with a significant coercivitv, which is a oromising magnetostrictive material.

关键词： mechanical alloying magnetostriction structure magnetic properties magnetostrictive composites

Radial Grip Rigidity of the Matching of Lengthened Shrink-fit Holder and Cutter in High-speed Milling

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 179-183页

作者： ZHOU Houming WANG chengyong DENG Jianxin PENG Ruitao School of Mechanical Engineering Xiangtan UniversityXiangtan 411105China Institute of Manufacturing Technology of Guangdong University of Technology Guangzhou 510006China

Though the lengthened shrink-fit holder (LSFH) is widely applied in high speed milling of the parts characterized by deep cavities at present, its design and selection mainly depends on the experience and lacks a correct theoretical guidance. In this paper, attention is focus on the radial grip rigidity of the matching of LSFH and cutter in high speed milling. Based on the experiment modal analysis (EMA) technique, an accurate finite element model of the matching of LSFH and cutter is established firstly. Subsequently, the influence of different interference, grip length and spindle speed on the grip rigidity of LSFH are analyzed. The analysis results show that there is a reasonable interference and grip length between the LSFH and cutter so that to have a steepless grip and have a good radial grip rigidity and at the same time to avoid the strength of LSFH to exceed it’s yield limit which will reduce the precision and service life of LSFH, besides when spindle speed reach a extension the weakening influence of the centrifugal force on the radial grip rigidity of the matching of LSFH and cutter should been taken into account. Finally, the finite element analysis results are verified based on the construction of measurement method of the grip rigidity and the results fit very well. The studies provide a theoretical basis for the design, selection and the serialization and standardization of the matching of LSFH and cutter.

关键词： Lengthened shrink-fit holder Finite element analysis Radial grip rigidity High speed milling

GENERATE ROUGH TOOL-PATHS FROM UNORGANIZED POINT-CLOUD DIRECTLY

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Chinese Journal of Mechanical Engineering 2007年第5期20卷 1-4页

作者： WU Shixiong WANG chengyong FAN Jingming School of Mechanical and Electrical Engineering Guangdong University of Technology Guangzhou 510006 China

An approach is presented to generate rough interference-free tool-paths directly from massive unorganized data in rough machining that is performed by machining volumes of material in a slice-by-slice manner. Unorganized point-cloud is firstly converted to cross-section data. Then a robust data-structure named tool-path net is constructed to save tool-path data. Optimal algorithms for partitioning sub-cut-areas and computing interference-free cutter-locations are put forward. Finally the tool-paths are linked in a zigzag milling mode, which can be transformed into a traveling sales man problem. The experiment indicates optimal tool paths can be acquired, and high computation efficiency can be obtained and interference can be avoided successfully.

关键词： Rough machining Tool path Unorganized point-cloud

Human neuromuscular junction three-dimensional organoid models and the insight in motor disorders

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Journal of Molecular Cell Biology 2021年第11期13卷 767-773页

作者： Kejing Zhang Lei Bai Wentao Xu chengyong Shen Department of Neurobiology The First Affiliated HospitalInstitute of Translational MedicineSchool of MedicineZhejiang UniversityHangzhou 310020China

The neuromuscular junction(NMJ),a peripheral synaptic connection between motoneurons and skeletal muscle fibers,controls *** of NMJs has been implicated in various motor *** of their large size and easy accessibility,NMJs have been extensively investigated in the neuroscience field and have greatly contributed to our understanding of the fundamental principles of synapses in the central nervous *** have tried multiple ways to develop models to recreate *** progress in the research and development of tissue-like organoids has made it possible to produce human NMJ three-dimensional(3D)models in vitro,providing an additional powerful strategy to study ***,we introduce the most recent advances of human embryonic stem cell-or induced pluripotent stem cell-derived organoids to model 3D NMJs.

关键词： neuromuscular junction organoid motor disorder

High-Speed Machining of Malleable Cast Iron by Various Cutting Tools Coated by Physical Vapor Deposition

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 299-316页

作者： Suyang Li Haisheng Lin Tingjie Zhang Jianbo Sui chengyong Wang School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Wenshan Business Information Management School Wenshan 530004China

The coating material of a tool directly affects the efficiency and cost of machining malleable cast ***,the machining adaptability of various coating materials to malleable cast iron has been insufficiently *** this paper,turning tests were conducted on cemented carbide tools with different coatings(a thick TiN/TiAlN coating,a thin TiN/TiAlN coating,and a nanocomposite(nc)TiAlSiN coating).All coatings were applied by physical vapor *** a comparative study of chip morphology,cutting force,cutting temperature,specific cutting energy,tool wear,and surface roughness,this study analyzed the cutting characteristics of the tools coated with various materials,and established the relationship between the cutting parameters and machining *** results showed that in malleable cast iron machining,the coating material significantly affects the cutting performance of the *** the three tools,the nc-TiAlSiN-coated carbide tool achieved the minimum cutting force,the lowest cutting temperature,least tool wear,longest tool life,and best surface ***,in comparisons between cemented-carbide and compacted-graphite cast iron machined under the same conditions,the wear mechanism of the coated tools was found to depend on the cast iron being ***,the performance requirements of a tool depend on multiple factors,and selecting an appropriately coated tool for a particular cast iron material is essential.

关键词： Malleable cast iron Tool-workpiece matching Cemented carbide coated tool PVD coating Dry turning

GENERATE TRIANGUUTED SURFACES FROM MASSIVE UNORGANIZED POINTS

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 93-95页

作者： WU Shixiong WANG chengyong CHEN Zichen School of Mechanical and Electrical Engineering Guangdong University of Technology Guangzhou 510090 China College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China

A region-growing method for reconstructing triangulated surfaces from massive unorganized points is presented. To save memory space, a ring data structure is adopted to build connections between points and triangulated surfaces. The data-structure allows the efficient retrieval of all neighboring vertices and triangles of a given vertice, To narrow the search range of adjacent points and avoid tuangle intersection, an influence area is defined for each active-edge, In the region-growing process of triangulated surfaces, a minimum-edge-angle-product algorithm is put forward to select an appropriate point to form a new triangle for an active edge. Results indicate that the presented method has high efficiency and needs less memory space, optimized triangulated surfaces with reliable topological quality can be obtained after triangulation,

关键词： Surface reconstruction Triangulated surface Unorganized points

Capturing and storage of CO_2 by micron-nano minerals:Evidence from the nature

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Chinese Journal Of Geochemistry 2011年第4期30卷 569-575页

作者： MAO Xumei TIAN Xike YU chengyong School of Environmental Studies and School of Material Sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

The increase of CO2 in atmosphere is a main factor leading to "greenhouse effect", which causes more and more serious global environmental problems. The reduction of CO2 is a challenge for the survival of human beings, and it is also a big technical problem. CO2 fluid-rock interaction is a key scientific problem involved in geo-logical storage. The CO2 fluid-rock interaction has a variety of multi-scale changes. Due to great differences in the quantity of surface atoms and surface energy between micron-nano-sized minerals, and ions and crystals, the speed and efficiency of CO2 fluid-rock interaction on a micron-nano scale are much higher than those on other scales. As is known from the natural world, the micron-nano structures of pores and the surface chemical modification of natural porous minerals (zeolite, diatomite, sepiolite, palygorskite, halloysite, etc.) should be further investigated, which can be used as the micron-nano -mineral porous materials with high capacity and high efficiency for capturing CO2. Through simulating the adsorption capacity and process of CO2 by minerals in the natural world, the micron-nano technology is applied to calcium- and magnesium-based minerals (olivine, pyroxene, feldspar, clay, etc.) so as to improve the activity of calcium and magnesium and enlarge the reaction contact area. In this way, the efficiency of capturing and storage of CO2 by calcium- and magnesium-based minerals can be greatly improved. These minerals can also be used as the micron-nano-mineral materials with large capacity and high efficiency for capturing and storing CO2.

关键词：二氧化碳排放量纳米尺度矿物质微米储存捕获纳米矿物材料证据

Low-temperature activation of methane over rare earth metals promoted Zn/HZSM-5 zeolite catalysts in the presence of ethylene

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Journal of Natural Gas Chemistry 2011年第3期20卷 243-248页

作者： Hengqiang Zhang Aiguo Kong Yongjie Ding chengyong Dai Yongkui Shan Department of Chemistry East China Normal University Shanghai 200062 China

At low temperature of 723 K, methane can be easily activated in the presence of ethylene in the feed, and converted to higher hydrocarbons （C2-C4） and aromatics （C6-C10）, through its reaction over rare metals modified Zn/HZSM-5 zeolite catalysts without undesirable carbon oxides formation. Methane can get 37.3% conversion over the above catalysts under low temperature, and the catalysts show a longer lifetime than usual metal supported HZSM-5 zeolite catalysts without adding any rare earth metals. The effects of methane activation over various rare earth metal promoted Zn/HZSM-5 catalysts on the products and influences of several reaction conditions such as temperature, catalyst lifetime and molar ratio of CH4/C2H4 have been discussed.

关键词： methane conversion HZSM-5 catalyst rare earth promoted

Mepanipyrim induces visual developmental toxicity and vision-guided behavioral alteration in zebrafish larvae

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Journal of Environmental Sciences 2023年第2期124卷 76-88页

作者： Chao Shen Yimei Cai Jialing Li chengyong He Zhenghong Zuo State Key Laboratory of Cellular Stress Biology School of Life SciencesXiamen UniversityXiamen 361005China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361005China

Mepanipyrim,an anilinopyrimidine fungicide,has been extensively used to prevent fungal diseases in fruit ***,research on mepanipyrim-induced toxicity in organisms is still very scarce,especially visual developmental ***,zebrafish larvae were employed to investigate mepanipyrim-induced visual developmental *** light andmonochromatic light stimuli-evoked escape experiments were used to investigate vision-guided ***,transcriptomic sequencing and real-time quantitative PCR assays were applied to assess the potential mechanisms of mepanipyrim-induced visual developmental toxicity and vision-guided behavioral *** results showed that mepanipyrim exposure could induce retinal impairment and vision-guided behavioral alteration in larval *** addition,the grk1b gene of the phototransduction signaling pathway was found to be a potential aryl hydrocarbon receptor(AhR)-regulated ***-induced visual developmental toxicity was potentially related to the AhR signaling ***,mepanipyrim-induced behavioral alteration was guided by the visual function,and the effects of mepanipyrim on long and middle wavelength light-sensitive opsins may be the main cause of vision-guided behavioral *** results provide insights into understanding the relationship between visual development and vision-guided behaviors induced by mepanipyrim exposure.

关键词： Danio rerio mepanipyrim visual developmental toxicity vision-guided behaviors phototransduction signaling pathway grk1b

Predication of topological states in the allotropes of group-Ⅳ elements

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Frontiers of Physics 2021年第6期16卷 120-127页

作者： chengyong Zhong National Laboratory of Solid State Microstructures and Department of Physics Nanjing University Collaborative Innovation Center of Advanced Microstructures Nanjing University Institute for Advanced Study Chengdu University

Three-dimensional(3 D) topological insulators(TIs) have been studied for approximately fifteen years,but those made from group-IV elements, especially Ge and Sn, seem particularly attractive owing to their nontoxicity, sizable intrinsic spin–orbit coupling(SOC) strength and natural compatibility with the current semiconductor industry. However, group-IV elemental TIs have rarely been reported,except for the low temperature phase of α-Sn under strain. Here, based on first-principles calculations,we propose new allotropes of Ge and Sn, named T5-Ge/Sn, as desirable TIs. These new allotropes are also highly anisotropic Dirac semimetals if the SOC is turned off. To the best of our knowledge,T5-Ge/Sn are the first 3 D allotropes of Ge/Sn that possess topological states in their equilibrium states at room temperature. Additionally, their isostructures of C and Si are metastable indirect and direct semiconductors. Our work not only reveals two promising TIs, but more profoundly, we justify the advantages of group-IV elements as topological quantum materials(TQMs) for fundamental research and potential practical applications, and thus reveal a new direction in the search for desirable TQMs.

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