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China Ocean Engineering 2024年第3期38卷 467-482页

作者： SHEN Zhong-xiang WANG Wen-qing XU Cheng-yue luo Jia-xin LIU Ren-wei School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

In this study,a common-node DEM-SPH coupling model based on the shared node method is proposed,and a fluid–structure coupling method using the common-node discrete element method-smoothed particle hydrodynamics(DS-SPH)method is developed using LS-DYNA *** DEM and SPH are established on the same node to create common-node DEM-SPH particles,allowing for fluid–structure *** simulations of various scenarios,including water entry of a rigid sphere,dam-break propagation over wet beds,impact on an ice plate floating on water and ice accumulation on offshore structures,are *** interaction between DS particles and SPH fluid and the crack generation mechanism and expansion characteristics of the ice plate under the interaction of structure and fluid are also *** results are compared with available data to verify the proposed coupling ***,the simulation results demonstrated that controlling the cutoff pressure of internal SPH particles could effectively control particle splashing during ice crushing failure.

关键词： common-node DEM-SPH fluid-structure interaction discrete element method smoothed particle hydrodynamics

The enhanced mechanical properties of SiC nanowires/Ba_(0.75)Sr_(0.25)Al_(2)Si_(2)O_(8) ceramics with embedded SiO_(2) interface

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Journal of Advanced Ceramics 2024年第7期13卷 933-941页

作者： Xin Li Xiaomeng Fan Haojie luo Xiaoke Lu Jimei Xue Fang Ye Yongsheng Liu Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

In this work,low-softening-temperature and low-modulus SiO_(2) was introduced as an embedded interface between SiC nanowires(SiCnws)and a Ba_(x)Sr_(1−x)Al_(2)Si_(2)O_(8) ceramic matrix to enhance strength and toughness of the *** the sintering process,molten SiO_(2) enhances the flowability of the ceramic powders and modifies the dispersion of *** strengthening effect of SiCnws was fully realized,and the flexural strength of the optimized ceramics reached 193±16 MPa,which represents an increase of 52.6%.After the formation of the embedded SiO_(2) interface with a low modulus,cracks can deflect along the SiCnws surface,which is consistent with the criterion of He and *** can effectively extend the crack propagation path,and the fracture toughness(K_(IC))is thus improved by 94.0%,reaching 3.1±0.5 MPa·m^(1/2).

关键词： multiphase ceramics SiO_(2) interface densification mechanical properties

Study on the thermally induced spindle angular errors of a five-axis CNC machine tool

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Advances in Manufacturing 2023年第1期11卷 75-92页

作者： Ji Peng Ming Yin Li Cao luo-Feng Xie Xian-Jun Wang Guo-Fu Yin School of Mechanical Engineering Sichuan UniversityChengdu610065People’s Republic of China

Thermally induced spindle angular errors of a machine tool are important factors that affect the machining accuracy of *** is critical to develop models with good generalization abilities to control these angular thermal ***,the current studies mainly focus on the modeling of linear thermal errors,and an angular thermal error model applicable to different working conditions has rarely been ***,the formation mechanism of the angular thermal error remains to be *** this study,an analytical modeling method was proposed by analyzing the formation and propagation chain of the spindle angular thermal errors of a five-axis computer numerical control(CNC)machine *** effects of the machine tool structure and position were considered in the modeling *** angular thermal error equations were obtained by analyzing the spatial thermoelastic deformation *** analytical model of the spindle angular thermal error was established based on the geometric relation between thermal *** model parameters were identified using the trust region least squares *** results showed that the proposed analytical model exhibited good generalization ability in predicting spindle pitch angular thermal errors under different working conditions with variable spindle rotational speeds,spindle positions,and environmental temperatures in different *** average mean absolute error(MAE),root mean square error(RMSE)and R2 in twelve different experiments were 4.7μrad,5.6μrad and 0.95,*** study provides an effective method for revealing the formation mechanism and controlling the spindle angular thermal errors of a CNC machine tool.

关键词： Machine tool Angular thermal errors Thermal error modeling Analytical model

Sourcing the merits of 3D integrated air cathodes for highperformance Zn-air batteries by bubble pump consumption chronoamperometry

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Nano Research 2024年第8期17卷 6951-6959页

作者： Mengxuan Li Linfeng Yu Hai Liu Chuanyi Zhang Jiazhan Li Liang luo Xiaoming Sun State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Zn-air batteries(ZABs)as a potential energy conversion system suffer from low power density(typically≤200 mW·cm^(−2)).Recently,three-dimensional(3D)integrated air cathodes have demonstrated promising performance over traditional twodimensional(2D)plane ones,which is ascribed to enriched active sites and enhanced diffusion,but without experimental ***,we applied a bubble pump consumption chronoamperometry(BPCC)method to quantitatively identify the gas diffusion coefficient(D)and effective catalytic sites density(ρEC)of the integrated air cathodes for ***,the D andρEC values can instruct consequent optimization on the growth of Co embedded N-doped carbon nanotubes(CoNCNTs)on carbon fiber paper(CFP)and aerophilicity tuning,giving 4 times D and 1.3 timesρEC over the conventional 2D Pt/C-CFP *** a result,using the CoNCNTs with half-wave potential of merely 0.78 V ***(Pt/C:0.89 V ***),the superaerophilic CoNCNTs-CFP cathode-based ZABs exhibited a superior peak power density of 245 mW·cm^(−2) over traditional 2D Pt/C-CFP counterparts,breaking the threshold of 200 mW·cm^(−2).This work reveals the intrinsic feature of the 3D integrated air cathodes by yielding exact D andρEC values,and demonstrates the feasibility of BPCC method for the optimization of integrated electrodes,bypassing trial-and-error strategy.

关键词： Zn-air batteries three-dimensional(3D)integrated air cathodes superaerophilic gas diffusion coefficient effective catalytic sites density

Influence of nanoparticle concentrations on flow boiling heat transfer coefficients of Al_2O_3/R141b in micro heat exchanger by direct metal laser sintering

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1714-1726页

作者： Jianyang Zhou Xiaoping luo Cong Deng Mingyu Xie Lin Zhang Di Wu Feng Guo School of Mechanical and Automobile Engineering South China University of Technology School of Mechanical and Marine Engineering Qinzhou University

Al2O3/R141b ＋ Span-80 nanorefrigerant for 0.05 wt.% to 0.4 wt.% is prepared by ultrasonic vibration to investigate the influence of nanoparticle concentrations on flow boiling heat transfer of Al2O3/R141b ＋ Span-80 in micro heat exchanger by direct metal laser sintering. Experimental results show that nanoparticle concentrations have significantly impact on heat transfer coefficients by homogeneity test of variances according to mathematical statistics. The heat transfer performance of Al2O3/R141b ＋ Span-80 nanorefrigerant is enhanced after adding nanoparticles in the pure refrigerant R141b. The heat transfer coefficients of 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.% Al2O3/R141 b ＋ Span-80 nanorefrigerant respectively increase by 55.0% 72.0%, 53.0% 42.3% and 39.9% compared with the pure refrigerant R141b. The particle fluxes from viscosity gradient, non-uniform shear rate and Brownian motion cause particles to migrate in fluid especially in the process of flow boiling. This migration motion enhances heat transfer between nanoparticles and fluid. Therefore, the heat transfer performance of nanofluid is enhanced. It is important to note that the heat transfer coefficients nonlinearly increase with nanoparticle concentrations increasing. The heat transfer coefficients reach its maximum value at the mass concentration of 0.1% and then it decreases slightly. There exists an optimal mass concentration corresponding to the best heat transfer enhancement. The reason for the above phenomenon is attributed to nanoparticles deposition on the minichannel wall by Scanning Electron Microscopy observation. The channel surface wettability increases during the flow boiling experiment in the mass concentration range from 0.2 wt.% to 0.4 wt.%. The channel surface with wettability increasing needs more energy to produce a bubble. Therefore, the heat transfer coefficients decrease with nanopartide concentrations in the range from 0.2 wt.% to 0.4 wt.%. In addition, a new corre

关键词： Nanoparticle Concentration Minichannel Sintering Flow boiling Heat transfer coefficient

Effect of Extrusion Strain Path on Microstructure and Properties of AZ31 Magnesium Alloy Sheet

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1257-1263页

作者： Qing-Shan Yang Bin Jiang Zu-Jian Yu Qing-Wei Dai Su-Qin luo School of Metallurgy and Material Engineering Chongqing University of Science and Technology Chongqing Academy of Science and Technology

The mechanical properties of AZ31 magnesium alloy sheets processed by different extrusion strain paths were examined in correlation with concurrent microstructure and texture evolution. The conventional extrusion（CE） and asymmetric extrusion（ASE） paths were performed on Mg alloy sheets. The textures at near surface and mid-layer of ASE sheets were various throughout sheet thickness direction as a result of extra asymmetric shear strain. This can stimulate the orientation of（0002） basal planes to incline approximately 12° toward the shear direction. Moreover, the basal texture of ASE sheet was weakened compared with CE one. Enhancing the ambient formability of extruded Mg alloy sheet fabricated by ASE path was accomplished by the tilted weak basal texture.

关键词： Mg alloy Extrusion Microstructure Texture Mechanical property Formability

Combining gas exchange and chlorophyll a fluorescence measurements to analyze the photosynthetic activity of drip-irrigated cotton under different soil water deficits

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Journal of Integrative Agriculture 2016年第6期15卷 1256-1266页

作者： luo Hong-hai Tsimilli-michael Merope ZHANG Ya-li ZHANG Wang-feng Key Laboratory of Oasis Ecology Agriculture Xinjiang Production and Construction Group Shihezi University Shihezi 832003 P. R. China Bioenergetics Laboratory University of Geneva Jussy-Geneva CH-1254 Switzerland

Gas exchange and chlorophyll a fluorescence were measured to study the effects of soil water deficit （75, 60 and 45% of field capacity, FC） on the photosynthetic activity of drip-irrigated cotton under field conditions. At light intensities above 1 200 IJmol m-2 s-1, leaf net photosynthetic rate （mn） at 60 and 45% FC was 0.75 and 0.45 times respectively than that of 75% FC. The chlorophyll content, leaf water potential and yield decreased as soil water deficit decreased. Fiber length was significantly lower at 45% FC than at 75% FC. The actual quantum yield of the photosystem II （PSII） primary photo- chemistry and the photochemical quenching were significantly greater at 60% FC than at 75% FC. The electron transport rate and non-photochemical quenching at 45% FC were 0.91 and 1.29 times than those at 75% FC, respectively. The amplitudes of the K- and L-bands were higher at 45% FC than at 60% FC. As soil water content decreased, active PSII reaction centers per chlorophyll decreased, functional PSII antenna size increased, and energetic connectivity between PSII units decreased. Electron flow from plastoquinol to the PSI end electron acceptors was significantly lower at 45% FC than at 75% FC. Similar to the effect on leaf Po, water deficit reduced the performance index （PIABs, tot） in the dark-adapted state. These results suggest that （i） the effect of mild water deficit on photosystem activity was mainly related to processes between plastoquinol and the PSI end electron acceptors, （ii） PSI end electron acceptors were only affected at moderate water deficit, and （iii） PIABs. tota can reliably indicate the effect of water deficit on the energy supply for cotton metabolism.

关键词： cotton drought JIP-test modulated fluorescence quenching analysis photosynthetic rate

From deep basin gas to diagenetic trap—An example from the Yulin Gas Field in the Ordos Basin

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Chinese Science Bulletin 2007年第21期52卷 2973-2983页

作者： ZHANG LiuPing luo XiaoRong MA XinHua CHEN MengJin WU MingHui Key Laboratory of Petroleum Resource Chinese Academy of Sciences Beijing 100029 China Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

In the updip portion of the Yulin Gas Field in the Ordos Basin, there are no any structural, stratigraphic and sedimentary lithologic seals. Using thin-section petrography, ultraviolet fluorescence microscopy, micro-thermometry and Raman microspectrometry, this paper finds out the diagenetic trap and studies the diagenetic history of this field. It was revealed that three phases of diagenesis and hydrocarbon charging happened in late Triassic, late Jurassic and the end of early Cretaceous respectively. In the first two phases, acid geofluid entered the reservoir and caused dissolution and cementation. Although the porosities had been increased, further compaction accompanying re-subsidence resulted in tight sandstone and conglomerates. Till the end of the early Cretaceous, bulk of gas migrated into the tight reservoir. Cementation, however, kept on in the updip portion of this field due to low gas saturation and formed the diagenetic trap. The mechanism for gas accumulation was changed from deep basin gas to diagenetic trap, which offers a sealing condition that can retain gas for much longer time.

关键词：天然气气田储气量天然气开发

Fabrication and mechanical properties of high-performance aluminum alloy

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Rare Metals 2014年第4期33卷 400-403页

作者： Wei-Wei Yang Zhi-Meng Guo Hui-Qin Cao Ji luo An-Ping Ye Institute of Advanced Materials and Technology University of Science and Technology Beijing

High-performance Al-Cu-Mg alloy was fabri- cated by high-energy ball milling, sintering, and hot extrusion. The microstructure and mechanical properties of the material were preliminarily investigated. Results show that the formation of liquid phase during sintering pro- motes the densification of the aluminum powders. A 97.1% theoretical density is achieved in this alloy after sintering. The material shows excellent mechanical prop- erties after extrusion and heat treatment. The ultimate tensile strength and yield strength of the extruded samples with heat treatment are 613 and 465 MPa, respectively.

关键词： Aluminum alloys Ball mill Sintering Extrusion Mechanical properties

Geological significance of the former Xiong'er Volcanic Belt on the southwestern margin of the North China Craton

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Frontiers of Earth Science 2019年第1期13卷 191-208页

作者： Guanxu CHEN Jinhai luo Huan XU Jia YOU Yifei LI Zichen CHE State Key Laboratory of Continental Dynamics (Northwest University) Department of GeologyNorthwest UniversityXi'an 710069China

The rock association of low-grade metasedimentary rocks and greenschists located within the Meso- Cenozoic Liupanshan Fault system on the southwestern margin of the North China Craton (NCC)is regarded as part of the Paleoproterozoic Xiong'er *** low- grade rocks are separated by normal faults,with the greenschist located in the hanging *** LA-ICP- MS U-Pb ages of the greenschists range from 2455 to 423 Ma,suggesting that they are not Paleoproterozoic in age. The protolith ages (206-194 Ma)of the greenschists were determined by LA-ICP-MS U-Pb dating of zircons from two siltstone *** petrology and geochemistry of the greenschists reveal that their protolith was continental tholeiitic basalt that formed in an extensional environment such as a continental ***,it is proposed that the protolith of the greenschists was a mafic volcanic rock of Late Triassic-Early Jurassic age and was metamorphosed during the Jurassic due to tectonism within the Liupanshan tectonic *** results show that the greenschists should be reclassified and removed from the Xiong'er Group,and explains why they differ so much from those of typical Xiong'er Group successions in other *** formation of the mafic volcanic rocks under conditions of continental rifting differs from that of coeval granitic rocks in the western Qinling Orogen,where the extension occurred during a post-collisional stage in the Late Triassic,which further suggests that the southwestern margin of the NCC became an extensional setting after the Late Triassic.

关键词： southwestern margin of the NCC Paleoproterozoic Xiong'er Group greenschist detrital zircon U-Pb geochronology Late Triassic to Early Jurassic