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Zoological Systematics 2019年第1期44卷 76-83页

作者： kang Lou juan Li Shuxia Wang College of Life Sciences Nankai University

The genus Orencostoma Moriuti, 1971 is recorded for the first time in China. Two new species, O. divulgatum Wang sp. nov. and O. semicirculum Wang sp. nov., are described. Photographs of adults, venations and male gen... 详细信息

关键词： Yponomeutioidea taxonomy new record

Design of ultrasonic elliptical vibration cutting system for tungsten heavy alloy

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Frontiers of Mechanical Engineering 2022年第4期17卷 163-180页

作者： Sen YIN Yan bao Yanan PAN Zhigang DONG Zhuji JIN Renke kang Key Laboratory for Precision and Non-traditional Machining Technology of the Ministry of Education School of Mechanical EngineeringDalian University of TechnologyDalian 116024China

Nanoscale surface roughness of tungsten heavy alloy components is required in the nuclear industry and precision *** this study,a high-performance ultrasonic elliptical vibration cutting(UEVC)system is developed to solve the precision machining problem of tungsten heavy alloy.A new design method of stepped bending vibration horn based on Timoshenko’s theory is first proposed,and its design process is greatly *** arrangement and working principle of piezoelectric transducers on the ultrasonic vibrator using the fifth resonant mode of bending are analyzed to realize the dual-bending vibration modes.A cutting tool is installed at the end of the ultrasonic vibration unit to output the ultrasonic elliptical vibration locus,which is verified by finite element *** vibration unit can display different three-degree-of-freedom(3-DOF)UEVC characteristics by adjusting the corresponding position of the unit and workpiece.A dual-channel ultrasonic power supply is developed to excite the ultrasonic vibration unit,which makes the UEVC system present the resonant frequency of 41 kHz and the maximum amplitude of 14.2μ*** microtopography and surface roughness are obtained by the cutting experiments of tungsten heavy alloy hemispherical workpiece with the UEVC system,which validates the proposed design’s technical capability and provides optimization basis for further improving the machining quality of the curved surface components of tungsten heavy alloy.

关键词： tungsten heavy alloy ultrasonic elliptical vibration cutting Timoshenko’s theory resonant mode of bending finite element method

Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei Xu Renke kang Bi Zhang Yuan Zhang Chenxu Wang Yan bao Zhigang Dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding

Preparation of chitosan and citric acid crosslinked membrane and its application in quasi-solid supercapacitors

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Rare Metals 2023年第2期42卷 430-437页

作者： Hao-Hang Xu Liang Yue Yang Tang Fan Liu Hong-Jiu Zhu Shu-juan bao Institute for Clean Energy&Advanced Materials School of Materials and EnergySouthwest UniversityChongqing400715China

Quasi-solid electrolytes promote the development of safe and flexible energy storage *** this work,a chitosan and citric acid crosslinked membrane is prepared by a freeze-thaw cross-linking method,in which the chemical crosslinking of chitosan and citric acid increase the viscoelastic behavior of the polymer membrane,and the freeze-thaw assist freeze drying process to create abundant interconnected open-pores and three-dimensional(3D)*** to the good viscoelasticity,excellent electrolyte loading capacity(596%)and high ion conductivity(7.7×10^(-3)S·cm^(-)1),as quasi-solid electrolyte,our proposed chitosan and citric acid crosslinked membrane helps ZnICCFT-ZnSO4lAC hybrid supercapacitor to delivers wide operating voltage,high specific capacity of 100.5 F·g^(-1)and stable cycle life(93%after1000 cycles),which suggests that our proposed freezethaw assisted freeze drying method has great potential in designing quasi-solid state electrolyte for energy storage device.

关键词： Quasi-solid electrolyte Chitosan Freeze-thaw Hybrid supercapacitor

Precipitation Behavior of Cu-1.9Be-0.3Ni-0.15Co Alloy During Aging

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 307-315页

作者： Yan-Chuan Tang Yong-Lin kang Li-juan Yue Xiao-Liang Jiao School of Materials Science and Engineering University of Science and Technology Beijing CNMC Ningxia Orient Group Co. Ltd.

In this paper,the evolutions of microstructure and mechanical properties of Cu-l.9Be-0.3Ni-0.15Co alloy were *** alloys in the condition of the solution treated（soft state） and 37% cold rolled（hard state） were aged at 320 ℃for different time,*** mechanical properties,electrical conductivity and microstructure of the alloy aged for different time were ***,the precipitation kinetics of Cu-1.9Be-0.3Ni-0.15Co alloys was investigated.X-ray diffraction and transmission electron microscopy results reveal that both continuous precipitation and discontinuous precipitation existed in the hard-state Cu-l.9Be-0.3Ni-0.15Co alloy during the whole aging process;the sequence of continuous precipitation is *** →γ″→γ′→γ.Furthermore,the precipitation transformation mechanism of softstate alloy is homogeneous nucleation,while hard-state alloy shows the heterogeneous nucleation（interface nucleation）with the nucleation rate of both states decaying rapidly to zero during aging at 320 ℃.

关键词： Cu-1.9Be-0.3Ni-0.15Co alloy Aging Microstructure Mechanical property Electrical property Precipitation kinetics

Fault-Tolerant Hamiltonicity and Hamiltonian Connectivity of BCube with Various Faulty Elements

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Journal of Computer Science & Technology 2020年第5期35卷 1064-1083页

作者： Gui-juan Wang Cheng-Kuan Lin Jian-Xi Fan Jing-Ya Zhou bao-Lei Cheng School of Computer Science and Technology Soochow UniversitySuzhou 215006China School of Computer Science and Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China College of Mathematics and Computer Science Fuzhou UniversityFuzhou 350108China

BCube is one kind of important data center *** and Hamiltonian connectivity have significant applications in communication *** far,there have been many results concerning fault-tolerant Hamiltonicity and fault-tolerant Hamiltonian connectivity in some data center ***,these results only consider faulty edges and faulty *** this paper,we study the fault-tolerant Hamiltonicity and the fault-tolerant Hamiltonian connectivity of BCube(n,k)under considering faulty servers,faulty links/edges,and faulty *** any integers n≥2 and k≥0,let BCn,k be the logic structure of BCube(n,k)and F be the union of faulty elements of BCn,k,Let fv/fe,and fs be the number of faulty servers,faulty edges,and faulty switches of BCiLbe(n,k),*** show that BCnik-F is fault-tolerant Hamiltonian if fv+fe+(n-1)/s≤(n-1)(k+1)-2 and BCn,k-F is fault-tolerant Hamiltonian-connected ifv,+fe+(n-1)fs≤(n-1)(k+1)-*** the best of our knowledge,this paper is the first work which takes faulty switches into account to study the fault-tolerant Hamiltonicity and the fault-tolerant Hamiltonian connectivity in data center networks.

关键词： data center network BCube fault-tolerance Hamiltonicity Hamiltonian connectivity

Spider Web‑Inspired Graphene Skeleton‑Based High Thermal Conductivity Phase Change Nanocomposites for Battery Thermal Management

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Nano-Micro Letters 2021年第11期13卷 308-321页

作者： Ying Lin Qi kang Han Wei Hua bao Pingkai Jiang Yiu‑Wing Mai Xingyi Huang Shanghai Key Lab of Electrical Insulation and Thermal Ageing The State Key Laboratory of Metal Matrix CompositesDepartment of Polymer Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China University of Michigan‑Shanghai Jiao Tong University Joint Institute Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Centre for Advanced Materials Technology(CAMT) School of AerospaceMechanical and Mechatronic Engineering J07The University of SydneySydneyNSW 2006Australia

Phase change materials(PCMs)can be used for efficient thermal energy harvesting,which has great potential for cost-effective thermal management and energy ***,the low intrinsic thermal conductivity of polymeric PCMs is a bottleneck for fast and efficient heat ***,it is also a challenge to achieve a high thermal conductivity for phase change nanocomposites at low filler *** constructing a three-dimensional(3D)thermally conductive network within PCMs can address these problems,the anisotropy of the 3D framework usually leads to poor thermal conductivity in the direction perpendicular to the alignment of *** by the interlaced structure of spider webs in nature,this study reports a new strategy for fabricating highly thermally conductive phase change composites(sw-GS/PW)with a 3D spider web(sw)-like structured graphene skeleton(GS)by hydrothermal reaction,radial freeze-casting and vacuum impregnation in paraffin wax(PW).The results show that the sw-GS hardly affected the phase transformation behavior of PW at low ***,sw-GS/PW exhibits both high cross-plane and in-plane thermal conductivity enhancements of~1260%and~840%,respectively,at an ultra-low filler loading of 2.25 vol.%.The thermal infrared results also demonstrate that sw-GS/PW possessed promising applications in battery thermal management.

关键词： Thermal conductivity Radial freeze-casting Phase change materials 3D graphene aerogel Thermal management

Synthesis of 5-vinyl-2-norbornene through Diels-Alder reaction of cyclopentadiene with 1,3-butadiene in supercritical carbon dioxide

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Chinese Chemical Letters 2017年第4期28卷 900-904页

作者： Fan-Qiang Meng Xiu-juan Feng Wan-Hui Wang Ming bao State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116023 China School of Petroleum and Chemical Engineering Dalian University of Technology Panjin 124221 China

An efficient method for the synthesis of 5-vinyl-2-norbornene from cyclopentadiene and 1,3-butadiene was *** Diels-Alder reaction of cyclopentadiene with 1,3-butadiene proceeded smoothly in supercritical carbon dioxide in the absence of any polymerization inhibitor to produce the corresponding5-vinyl-2-norbornene in satisfactory yield with high selectivity.

关键词： 5-Vinyl-2-norbornene Diels-Alder reaction Cyclopentadiene 1 3-Butadiene Supercritical carbon dioxide

A retrieval and validation method for shelterbelt vegetation fraction

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Journal of Forestry Research 2013年第2期24卷 357-360页

作者： DENG Rong-xin WANG Wen-juan LI Ying ZHAO Dong-bao Institute of Resources and Environment North China Institute of Water Resources and Electric Power Department of Resources and Environmental Sciences Henan University of Economics and Law

Shelterbelts are important in defending against natural disaster and maintaining ecological balances in farmland. Understanding of the shelterbelt vegetation fraction is fundamental to regional research of shelterbelts using remote sensing. We used SPOT5 imagery with 10×10m spatial resolution in combination with knowledge of the characteristics of shelterbelts to develop a method for retrieval of the vegetation fraction of shelterbelts by the pixel un-mixing model. We then used the method to retrieve values for shelterbelts in study area. By combining the parameters of photographic images with characteristics of shelterbelts, we developed a method for measuring the vegetation fraction of shelterbelts based on an advanced photographic method. We then measured the actual values to validate the retrieval result. The multiple correlation coefficients between the retrieved and measured values were 0.715. Our retrieval and measuring methods presented in this paper accurately reflect field conditions. We suggest that this method is useful to describe shelterbelt structure using remote sensing.

关键词： shelterbelt vegetation fraction retrieval vegetation fraction measuring remote sensing

Effects of Nb on the microstructure and mechanical properties of 38MnB5 steel

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1181-1190页

作者： Li Lin bao-shun Li Guo-ming Zhu Yong-lin kang Ren-dong Liu School of Material Science and Engineering University of Science and Technology BeijingBeijing 100083China Ansteel Technology Center Anshan 114009China

The effects of the microalloying element niobium(Nb) on the microstructure and mechanical properties of the hot stamped steel 38 Mn B5 were investigated. The impact of Nb addition on the microstructure was studied through scanning electron microscopy(SEM), transmission electron microscopy(TEM), and X-ray diffraction(XRD). The experimental results indicated that the microstructures of the steel containing Nb were finer than those of the steel without Nb. Moreover, Nb mainly presented as a second-phase particle in 38MnB5 steel, and the particles included Nb carbonitrides. In addition, the tensile strength and elongation of the hot rolled and hot stamped steels were also measured, and they demonstrated that the appropriate addition of Nb was beneficial to the mechanical properties of 38 MnB5. Under the same conditions, the tensile strength of 38 MnB5 Nb was higher than that of 38 MnB5, which increased from 2011 to 2179 MPa. The yield strength also increased from 1316 to 1476 MPa, and the elongation increased from 5.92% to 6.64%. Overall, Nb had a positive effect on the performance of the hot stamped steel.

关键词： hot stamping steel CCT curve microstructure mechanical properties precipitation