检索结果-南通市图书馆

Acta Mechanica Solida Sinica 2015年第6期28卷 693-705页

作者： Yiming Fu Yang chen Xuefei shao State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan University College of Mechanical and Vehicle Engineering Hunan University

The elasto-plastic postbuckling of fiber metal laminated beams with delamination and the energy release rate along the delamination front are discussed in this paper. Considering geometrical nonlinearity, thermal environment and geometrical initial imperfection, the incremental nonlinear equilibrium equations of delaminated fiber metal laminated beams are established, which are solved using the differential quadrature method and iterative method. Based on these, according to the J-integral theory, the elasto-plastic energy release rate is studied. The effects of some important parameters on the elasto-plastic postbuckling behavior and energy release rate of the aramid reinforced aluminum laminated beams are discussed in details.

关键词： fiber metal laminated beams delamination temperature effect elasto-plastic post- buckling elasto-plastic energy release rate

Position, Singularity and Workspace Analysis of 3-PSR-O Spatial Parallel Manipulator

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2015年第3期28卷 437-450页

作者： shao Jiejie chen Wenyu FU Xin State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

Although the parallel mechanisms have the advantages of high accuracy, velocity, stiffness, and payload capacity, the shortcomings of the space utilization and workspace limit the applications in the confined space. A novel 3 degrees of freedom spatial parallel manipulator 3-PSR-O（prismatic-spherical-revolute） is proposed, which possesses a compact architecture and extended workspace while maintaining the inherent advantages of the parallel mechanisms. The direct-inverse position, singularity and workspace are investigated. The mapping method is adopted in the position analysis, and the closed form solution is derived in the form of a six order equation. The singularity analysis of the mechanism is also carried out based on the geometrical constraints, including six singularity boundaries. A feature boundary, which is independent of the prismatic joints＇ stroke limit, is obtained by integrating the six singularity boundaries. According to the formation of the reachable workspace, a concept of basic workspace is also introduced and presented in the analytical way. By demarcating the basic workspace along the central height with the feature boundary, the reachable workspace can be derived and analyzed more efficiently. Finally, a comparative study on the space utilization between the 3-PSP parallel mechanism and the new mechanism is also presented. The area of feature boundary of the new mechanism is about 140% of the 3-PSP parallel mechanism, while its installation radius is only 1/2 of the 3-PSP parallel mechanism. The proposed parallel mechanism shows great space utilization, and is ideally suited for applications in confined space occasions such as immersion lithography, nano-imprint etc.

关键词： spatial-planar parallel mechanism direct-inverse position analysis reachable workspace basic workspace feature boundary

Dynamical phase-field model of coupled electronic and structural processes

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1223-1229页

作者： Tiannan Yang long-Qing chen Department of Materials Science and Engineering The Pennsylvania State UniversityUniversity ParkPA16802USA

Many functional and quantum materials derive their functionality from the responses of both their electronic and lattice subsystems to thermal,electric,and mechanical stimuli or *** we propose a dynamical phase-field model for predicting and modeling the dynamics of simultaneous electronic and structural processes and the accompanying mesoscale pattern evolution under static or ultrafast external *** an illustrative example of application,we study the transient dynamic response of ferroelectric domain walls excited by an ultrafast above-bandgap light *** discover a two-stage relaxational electronic carrier evolution and a structural evolution containing multiple oscillational and relaxational components across picosecond to nanosecond *** phase-field model offers a general theoretical framework which can be applied to a wide range of functional and quantum materials with interactive electronic and lattice orders and phase transitions to understand,predict,and manipulate their ultrafast dynamics and rich mesoscale evolution dynamics of domains,domain walls,and charges.

关键词： electronic structural phase

Influence of groove surface texture on temperature rise under dry sliding friction

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2016年第2期59卷 183-190页

作者： WU Wei shao TianMin chen GuiMing State Key Laboratory of Tribology Tsinghua University Beijing 100084 China Xi'an Research Institute of High Technology Xi'an 710025 China

Parallel groove surface textures with different area densities were fabricated on ASTM 1045 steel. Friction tests were con- ducted under dry sliding condition. Temperature rise, friction coefficient and wear of both the textured and untextured speci- mens were studied. An embedded K-type thermocouple beneath the friction surfaces was employed to measure frictional tem- perature rise. The results indicated that the temperature rise of the textured specimen was obviously reduced compared with that of the untextured specimen, although the difference between the friction coefficients was not significan.. The specimen with high texture density exhibited a small temperature rise. The difference in temperature rise between the specimens with different texture densities can be primarily attributed to differences in heat dissipation and energy allocation between the tri- bo-pairs caused by the textured structure. The energy consumed by wear and plastic deformation was small in ~：omparison with the total energy input by friction, thus, the influence of these factors on temperature rise can be considered to be~ negligible.

关键词： groove surface texture temperature rise heat dissipation wear plastic deformation

Partial oxidation of dimethyl ether to H_2/syngas over supported Pt catalyst

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2008年第1期17卷 75-80页

作者： Yazhong chen Zongping shao Nanping Xu State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing University of Technology Nanjing 210009 Jiangsu China

Dimethyl ether （DME） is a non-toxic fuel with high H/C ratio and high volumetric energy density, and could be served as an ideal source of H2/syngas production for application in solid oxide fuel cells （SOFC）. This study presents results of DME partial oxidation over a 1.5 wt% Pt/Ce0.4Zr0.6O2 catalyst under the condition of gas hourly space velocity （GHSV） of 15000-60000 ml/（g·h）, molar ratio of O2/DME of 0.5 and 500-700 ℃, and this temperature range was also the operation temperature range for intermediate temperature SOFC. The results indicated that the catalyst showed good activity for the selective partial oxidation of DME to H2/syngas. Under the working conditions investigated, DME was completely converted. Increase in reaction temperature enhanced the amount of syngas, but lowered the H2/CO ratio and yield of methane; while increase in reaction GHSV resulted in only slight variation in the distribution of products. The good catalytic activity of Pt supported on Ce0.4Zr0.6O2 for the partial oxidation of DME may be directly associated with the good oxygen storage capacity of the support, which is worth of further investigation to develop materials for application in SOFC.

关键词： dimethyl ether partial oxidation Pt/Ce0.4Zr0.6O2 syngas solid oxide fuel cell

CONVERGENCE ANALYSIS OF MORLEY ELEMENT ON ANISOTROPIC MESHES

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2006年第2期24卷 169-180页

作者： Shi-peng Mao shao-chun chen ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China Department of Mathematics Zhengzhou University Zhengzhou 450052 China

The main aim of this paper is to study tile convergence of a nonconforming triangular plate element-Morley element under anisotropic meshes. By a novel approach, an explicit bound for the interpolation error is derived for arbitrary triangular meshes （which even need not satisfy the maximal angle condition and the coordinate system condition ）, the optimal consistency error is obtained for a family of anisotropically graded finite element meshes.

关键词： Anisotropic meshes Interpolation error Consistency error Morley element.

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

From waste to wealth:Coal tar residue derived carbon materials as low-cost anodes for potassium-ion batteries

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 464-475页

作者： Zhonghua Lu Jun Shen Xin Zhang Lingcong Chao Liang chen Ding Zhang Tao Wei Shoudong Xu College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Chemistry Taiyuan University of TechnologyTaiyuan 030024China School of Chemical Engineering and Pharmacy Wuhan Institute of TechnologyWuhan 430205China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

Carbon materials are widely recognized as highly promising electrode materials for various energy storage system *** tar residues(CTR),as a type of carbon-rich solid waste with high value-added utilization,are crucially important for the development of a more sustainable *** this study,we employed a straightforward direct carbonization method within the temperature range of 700-1000℃to convert the worthless solid waste CTR into economically valuable carbon materials as anodes for potassium-ion batteries(PIBs).The effect of carbonization temperature on the microstructure and the potassium ions storage properties of CTR-derived carbons(CTRCs)were systematically explored by structural and morphological characterization,alongside electrochemical performances *** on the co-regulation between the turbine layers,crystal structure,pore structure,functional groups,and electrical conductivity of CTR-derived carbon carbonized at 900℃(CTRC-900H),the electrode material with high reversible capacity of 265.6m Ah·g^(-1)at 50 m A·g^(-1),a desirable cycling stability with 93.8%capacity retention even after 100 cycles,and the remarkable rate performance for PIBs were ***,cyclic voltammetry(CV)at different scan rates and galvanostatic intermittent titration technique(GITT)have been employed to explore the potassium ions storage mechanism and electrochemical kinetics of *** indicate that the electrode behavior is predominantly governed by surface-induced capacitive processes,particularly under high current densities,with the potassium storage mechanism characterized by an“adsorption-weak intercalation”*** work highlights the potential of CTR-based carbon as a promising electrode material category suitable for high-performance PIBs electrodes,while also provides valuable insights into the new avenues for the high value-added utilization of CTR.

关键词： coal tar residue carbon materials anode potassium-ion batteries high value-added

Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： chen chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

Line Aging Assessment in Distribution Network Based on Topology Verification and Parameter Estimation

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1658-1668页

作者： Zhi Wu Huan long Chang chen School of Electrical Engineering Southeast UniversityNanjing China IEEE Maintenance Branch Company State Grid Jiangsu Electric Power Company Ltd.Nanjing China

The aging of lines has a strong impact on the economy and safety of the distribution *** paper proposes a novel approach to conduct line aging assessment in the distribution network based on topology verification and parameter *** topology verification,the set of alternative topologies is firstly generated based on the switching *** best-matched topology is determined by comparing the difference between the actual measurement data and calculated voltage magnitude curves among the alternative ***,a novel parameter estimation approach is proposed to estimate the actual line parameters based on the measured active power,reactive power,and voltage magnitude *** includes two stages,i.e.,the fixed-step aging parameter(FSAP)iteration,and specialized Newton-Raphson(SNR)*** theoretical line parameters of the best-matched topology are taken as a warm start of FSAP,and the fitted result of FSAP is further renewed by the *** on the deviation between the renewed and theoretical line parameters,the aging severity risk level of each line is finally quantified through the risk assessment *** experiments on the modified IEEE 33-bus and 123-bus systems demonstrate that the proposed approach can effectively conduct line aging assessment in the distribution network.

关键词： Line aging topology verification parameter estimation risk assessment Newton-Raphson iteration