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Science China Earth Sciences 2014年第6期57卷 1192-1198页

作者： chen yuxiang LIU Xi ZHOU YongSheng The Key Laboratory of Orogenic Belts and Crustal Evolution MOE Peking University School of Earth and Space Sciences Peking University The State Key Laboratory of Earthquake Dynamics Institute of Geology Earthquake Administration

Three Dimensional Finite Element Method(3D-FEM)has been used to model the deviatoric stress field in a forsterite aggregate with a sandwich geometry:two forsterite cubes aligned in the same crystallographic orientation(the"breads")sandwich a third forsterite cube(the"filling"),which might have an identical or different crystallographic *** results show that there is no von Mises stress in the forsterite sandwich if the sandwiching and sandwiched forsterite cubes are aligned in the same crystallographic *** the crystallographic orientations are different,however,von Mises stress and heterogeneous stress distribution occur both along the boundary and in the forsterite *** the investigated P-T conditions(up to 6.4GPa and 500°C),the resulted deviatoric stress is much lower than the yield strength of forsterite,so that higher P,higher T,or other means to create higher deviatoric stress is necessary,in order to constrain the yielding behavior of forsterite.

关键词： 3D-FEM forsterite aggregate crystallographic orientation stress distribution

Effect of particle motion on the hydraulic collection of coarse spherical particles

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Acta Mechanica Sinica 2020年第1期36卷 72-81页

作者： yuxiang chen Hong Xiong Hui cheng Chunliang Yu Jiahua Xie Institute of Deep-sea Science and Engineering Chinese Academy of SciencesSanya572000China

Deep-sea mining,through which shattered coarse solid mineral resources are hydraulically collected and transported,is a promising solution for problems associated with resource *** study reports some interesting phenomena observed in a series of upward pumping experiments conducted on a coarse sphere with a 2-cm *** sphere was hydraulically lifted using a vertical pipe with a 5-cm radius suspended above the ***,the tangential motion benefited the *** discrete element method-computational fluid dynamics was used to investigate the collection mechanism;this method was used to simulate the collecting processes of the sphere under different initial motion *** simulated results agreed well with the experimental *** vortices over the sphere induced by its motion coupled with the main stream mainly provide sufficient lift force to raise the sphere.

关键词： Solid-liquid two-phase flow Deep-sea mining CFD-DEM

Cryo-EM structure of human κ-opioid receptor-G_(i) complex bound to an endogenous agonist dynorphin A

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Protein & Cell 2023年第6期14卷 464-468页

作者： yuxiang chen Bo chen Tingting Wu Fangfang Zhou Fei Xu iHuman Institute ShanghaiTech UniversityShanghai 210210China School of Life Science and Technology ShanghaiTech UniversityShanghai 210210China Center for Excellence in Molecular Cell Science Shanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China

Dear Editor,The opioid receptor family is divided into four subtypes each paired with their cognate peptide ligand:theμ-opioid receptor(MOR)withβ-endorphin,K-opioid receptor(KOR)with dynorphin A and B,o-opioid receptors(DOR)with enkephalin,and nociceptin opioid receptor(NOR)with nociceptin(Faouzi et al.,2020).These four opioid receptors all primarily couple to heterotrimeric G/G。proteins as well as mediatingβ-arrestin1/2 signaling pathway(Ferre et al.,2019).Activation of these receptors by distinct ligands is linked to a series of physiological responses,such as release of hormones,pain adjustment,drug addiction,stress,and mood regulation(Che et al.,2018).

关键词： structure primarily release

Uniform MnO2 nanostructures supported on hierar- chically porous carbon as efficient electrocatalysts for rechargeable Li-O2 batteries

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Nano Research 2015年第1期8卷 156-164页

作者： Xiaopeng Han Fangyi cheng chengcheng chen yuxiang Hu Jun chen Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Collaborative InnovationCenter of Chemical Science and Engineering Nankai University Tianjin 300071 China

Through in situ redox deposition and growth of MnO2 nanostructures on hierarchically porous carbon （HPC）, a MnOR/HPC hybrid has been synthesized and employed as cathode catalyst for non-aqueous Li-O2 batteries. Owing to the mild synthetic conditions, MnO2 was uniformly distributed on the surface of the carbon support, without destroying the hierarchical porous nanostructure. As a result, the as-prepared MnO2/HPC nanocomposite exhibits excellent Li-O2 battery performance, including low charge overpotential, good rate capacity and long cycle stability up to 300 cycles with controlling capacity of 1,000 mAh·g^-1. A combination of the multi-scale porous network of the shell-connected carbon support and the highly dispersed MnO2 nanostructure benefits the transportation of ions, oxygen and electrons and contributes to the excellent electrode performance.

关键词： lithium-oxygen batteries manganese oxide nanocomposite catalyst oxygen electrochemistry

Experimental investigation of critical suction velocity of coarse solid particles in hydraulic collecting

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Acta Mechanica Sinica 2021年第4期37卷 613-619,I0002页

作者： Yan Zhang Xiaobing Lu Xuhui Zhang yuxiang chen Hong Xiong Lianghua Zhang Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya 572000China

Hydraulic collecting and pipe transportation are regarded as an efficient way for exploiting submarine mineral resources such as the manganese nodules and *** particles on the surface of the sea bed are sucked by a pipe during the mining and crushing of the *** this paper,the critical suction velocity for lifting the coarse particles is investigated through a series of laboratory experiments,and the solid-liquid two-phase flow characteristics are *** on the dimensional analysis,the geometric similarity is found between actual exploitation process and model test with the same kind of *** controlling dimensionless parameters such as the hydraulic collecting number,the relative coarse particle diameter,the relative suction height,and the density ratio are deduced and *** results show that the logarithm in base 10 of the hydraulic collecting number increases approximately linearly with the increase of the relative suction height,while decreases with the relative particle diameter.A fitting formula for predicting the critical suction velocity is presented according to the experimental results.

关键词： Hydraulic collecting Critical suction velocity Coarse particles Deep sea mining Dimensional analysis

Responses of estuarine salinity and transport processes to sea level rise in the Zhujiang(Pearl River) Estuary

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Acta Oceanologica Sinica 2016年第5期35卷 38-48页

作者： chen yuxiang ZUO Juncheng ZOU Huazhi ZHANG Min ZHANG Kairong Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai University Key Laboratory of the Zhujiang Estuarine Dynamics and Associated Process Regulation Ministry of Water Resources South China Sea Marine Prediction Center State Oceanic Administration Yalong River Hydropower Development Co. Ltd.

Understanding the changes of hydrodynamics in estuaries with respect to magnitude of sea level rise is important to understand the changes of transport process. Based on prediction of sea level rise over the 21st century, the Zhujiang（Pearl River） Estuary was chosen as a prototype to study the responses of the estuary to potential sea level rise. The numerical model results show that the average salt content, saltwater intrusion distance, and stratification will increase as the sea level rises. The changes of these parameters have obvious seasonal variations. The salt content in the Lingdingyang shows more increase in April and October（the transition periods）. The saltwater intrusion distance has larger increase during the low-flow periods than during the highflow periods in the Lingdingyang. The result is just the opposite in Modaomen. The stratification and its increase are larger during the low-flow periods than during the high-flow periods in Lingdingyang. The response results of transport processes to sea level rise demonstrate that：（1） The time of vertical transport has pronounced *** increased tidal range and currents would reinforce the vertical mixing, but the increased stratification would weaken the vertical exchange. The impact of stratification changes overwhelms the impact of tidal changes. It would be more difficult for the surface water to reach the bottom.（2） The lengthways estuarine circulation would be strengthened. Both the offshore surface residual current and inshore bottom residual current will be *** whole meridional resident flow along the transect of the Lingdingyang would be weakened. These phenomena are caused by the decrease of water surface slope（WWS） and the change of static pressure with the increase of water depth under sea level rise.

关键词： sea level rise salinity stratification transport process Zhujiang Estuary

Phase evolution and mechanical properties of low-activation refractory high-entropy alloy Ti_(1.5)ZrV_(0.5)Ta_(0.5)

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Journal of Materials Science & Technology 2024年第7期174卷 145-156页

作者： yuxiang chen Ningyu Li Yijie Wang Kang Liu Yongqin Chang Mingyang Li School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China

A novel low-activation Ti_(1.5)ZrV_(0.5)Ta_(0.5)refractory high-entropy alloy(RHEA)was designed as a potential candidate for nuclear reactor *** room temperature,it had an elongation of 8.4%and a yield strength of 1096 *** phase evolution of this alloy and its effect on properties was *** 400℃,the solid solution bcc 1 transformed into the fcc phase and bcc 2 phase,and theωphase andαphase also *** 600℃,theωphase andαphase disappeared,and the microstructure of the alloy was composed of the fcc phase and bcc 2 *** the temperature was up to 1200℃,the fcc phase and bcc 2 phase re-transformed into solid solution bcc 1 *** precipitation ofωphase andαphase caused a sharp increase in strength and a decrease in ***,the appearance of the fcc phase led to a simultaneous decrease in strength and ductility,due to larger stress concentrations at the fcc/bcc ***,the formation mechanism of each phase in the alloy was discussed in detail.

关键词： Low-activation Refractory high-entropy alloy Phase evolution Phase formation mechanism Strengthening mechanism

Enhanced mechanical property by introducing bimodal grains structures in Cu-Ta alloys fabricated by mechanical alloying

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Journal of Materials Science & Technology 2024年第5期172卷 104-112页

作者： Ningyu Li Yongqin Chang Mingyang Li yuxiang chen Xinrui Luo Shichao Pei Fan Yang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China

Dispersion-strengthened copper alloys can achieve ultra-high strength,but usually at the expense of *** this study,a strategy for overcoming strength-ductility tradeoffof Cu alloys is realized through the introduction of bimodal grains ***-Ta alloys with only 0.5 at.%Ta content were successfully prepared by mechanical alloying combined with spark plasm *** samples prepared by one-step and two-step ball milling methods are named as Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ),*** microstructural characterizations revealed that ultra-fine equiaxed grains with uniformly dispersed Ta precipitates were obtained in the Cu-Ta *** strength of 377 MPa for yield strength together with elongation of∼8%was obtained in Cu-Ta(Ⅰ).Bimodal grains structures composed of fine-grain zones and coarse-grain zones were successfully introduced into Cu-Ta(Ⅱ)by a two-step ball milling approach,and both yield strength(463 MPa)and elongation(∼15%)were significantly synergistic *** hardness values of both Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)were almost kept nearly constant with the increase of annealing time,and the softening temperatures of Cu-Ta(Ⅰ)and Cu-Ta(Ⅱ)are 1018 and 1013℃,reaching 93.9%and 93.5%T m of pure Cu(1083℃),*** reveals that the Cu-0.5 at.%Ta alloys exhibit excellent thermal stability and exceptional softening *** nanoclusters with semi-coherent structures play an essential role in enhancing the strength and microstructural stability of *** structures are beneficial to the activation of back stress strengthening and the initiation and propagation of microcracks,thus obtaining the extraordinary combination of strength and *** study provides a new way to fabricate dispersion-strengthened Cu alloys with high strength,high elongation,excellent thermal stability and softening resistance,which have potential application value in the field of the future fusion reactor.

关键词： Cu-Ta alloy Mechanical alloying Ta precipitates Bimodal structures Mechanical property

A novel requirement analysis approach for periodic control systems

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Frontiers of Computer Science 2013年第2期7卷 214-235页

作者： Zheng WANG Geguang PU Jiangwen LI yuxiang chen Yongxin ZHAO Mingsong chen Bin GU Mengfei YANG Jifeng HE Shanghai Key Laboratory of Trustworthy Computing Software Engineering Institute East China Normal UniversityChina Shanghai 200241 Beijing Institute of Control Engineering China Beijing 100080 School of Computing National University of SingaporeSingapore Singapore 119077 China Academy of Space Technology China Beijing 100094

Periodic control systems （PCSs） are widely used in real-time embedded system domain. However, traditional manual requirement analysis assumes the expert knowledge, which is laborious and error-prone. This paper proposes a novel requirement analysis approach, which supports the automated validation of the informal requirement specifi- cations. Based on the normalized initial requirement docu- ments, our approach can construct an intermediate SPARDL model with both formal syntax and semantics. To check the overall system behaviors, our approach can transform the SPARDL models into executable code for simulation. The derived prototype simulator from SPARDL models enables the testing-based system behavior validation. Moreover, our approach enables the analysis of the dataflow relations in SPARDL models. By revealing input/output and affecting re- lations, our dataflow analysis techniques can help software engineers to figure out the potential data dependencies be- tween SPARDL modules. This is very useful for the module reuse when a new version of the system is developed. A study of our approach using an industry design demonstrates the practicality and effectiveness of our approach.

关键词： SPARDL simulation dataflow analysis codegeneration

HY-1C Coastal Zone Imager observations of the suspended sediment content distribution details in the sea area near Hong Kong-Zhuhai-Macao Bridge in China

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Acta Oceanologica Sinica 2022年第11期41卷 126-138页

作者： Lina Cai Minrui Zhou Xiaojun Yan Jianqiang Liu Qiyan Ji yuxiang chen Juncheng Zuo Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316004China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China South China Sea Fisheries Research Institute Chinese Academy of Fishery SciencesGuangzhou 510300China College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China

The impacts of the Hong Kong-Zhuhai-Macao Bridge(HKZMB)on suspended sediment content(SSC)were analysed in the Zhujiang River Estuary based on data from HY-1C,which was launched in September 2018 in China,carrying Coastal Zone Imager(CZI)and Chinese Ocean Color and Temperature Scanner on it.A new SSC inversion model was established based on the relationship between in-situ SSC and the remote sensing reflectance in red and near-infrared bands of CZI ***-1C satellite data obtained from October to December 2019 were applied to retrieve SSC in the Zhujiang River *** results show that SSC around the HKZMB is ranging from 20 mg/L to 95 mg/*** change obviously on two sides of the *** flooding and ebbing period,SSC increases obviously downstream of the *** difference between upstream and downstream is ranging from 5 mg/L to 20 mg/*** flowing across the HKZMB,the change trend of SSC in most places upstream and downstream is almost the same that SSC downstream of the bridge is higher than SSC *** tidal currents interact with bridge piers,inducing vortexes downstream,leading the sediment to re-suspend downstream of the bridge *** factors,including seafloor topography and wind,can also contribute to the distribution of SSC in the Zhujiang River Estuary.

关键词： HY-1C Coastal Zone Imager(CZI) Hong Kong-Zhuhai-Macao Bridge suspended sediment content Zhujiang River Estuary