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A new 3D plastoelastohydrodynamic lubrication model for rough surfaces

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Friction 2024年第6期12卷 1176-1193页

作者： Shengyu YOU jinyuan TANG Qiang WANG State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China

Plastoelastohydrodynamic lubrication of rough surfaces(R-PEHL)is a cutting-edge area of research in interface fluid-structure coupling *** existing R-PEHL model calculates the elastic-plastic deformation of rough surface by the Love equation in a semi-infinite space smooth surface,which deviates from the actual ***,it is an innovative work to study the exact solution of elastic-plastic deformation of rough surface and its influence on the solution results of R-PEHL *** this paper,a new contact calculation model of plastoelastohydrodynamic lubrication(PEHL)with three-dimensional(3D)rough surface is proposed by integrating numerical method of EHL and finite element *** new model eliminates an original error introduced by the assumption of semi-infinite space in contact calculation,providing wide applicability and high *** the given rough surfaces and working conditions,the study reveals that:(1)the oil film pressure calculated by the new model is lower than that of the smooth surface in semi-infinite space by 200–800 MPa;(2)the Mises stress of the new model is 2.5%–26.6%higher than that of the smooth surface in semi-infinite space;(3)compared with the semi-infinite space assumption,the rough surface plastic deformation of the new model is increased by 71%–173%,and the local plastic deformation singularity may appear under the semi-infinite space assumption;(4)the plastic deformation caused by the first contact cycle on the rough surface of the new model accounts for 66.7%–92.9%of the total plastic deformation,and the plastic deformation of the semi-infinite space accounts for 50%–83.3%.This study resolves the contradiction between the smooth surface assumption and the rough surface in the existing R-PEHL model,establishing a solid logic foundation for the accurate solution of R-PEHL model.

关键词： rough surface plastoelastohydrodynamic lubrication(PEHL) asperity plastic deformation semi-infinite space

heterogeneous hybrid immunity against Omicron variant JN.1 at 11 months following breakthrough infection

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Signal Transduction and Targeted Therapy 2024年第8期9卷 3170-3172页

作者： Xuan he Jingyou Yu Jiajing Jiang jinyuan Liu Qi Qi Dan Liu Weimin Li Department of Pulmonary and Critical Care Medicine Precision Medicine Key Laboratory of Sichuan ProvinceState Key Laboratory of Respiratory Health and MultimorbidityWest China HospitalSichuan UniversityChengduSichuanChina Guangzhou National Laboratory Bio-lslandGuangzhouGuangdongChina Sichuan Center for Disease Control and Prevention ChengduSichuanChina

Dear Editor,Due to the ongoing evolution of SARS-CoV-2 and waning immunity following COVID-19 vaccination,breakthrough infections have become common *** exposure to viral antigens during different COVID-19 waves and vaccination contribute to the unique"hybrid immunity"-immune protection conferred by the combined vaccination and natural infection in individuals.

关键词： immunity vaccination infection

Simultaneous measurement of distance and speed using frequency-modulated continuous-wave self-mixing interferometry and all-phase fast Fourier transform

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Chinese Optics Letters 2024年第7期22卷 29-34页

作者： jinyuan Yuan Bin Liu School of Physics and Optoelectronics Xiangtan UniversityXiangtan 411105China SECTE University of WollongongWollongong NSW 2522Australia

In this work,we propose a method using frequency-modulated continuous-wave(FMCW)self-mixing interferometry(SMI)and all-phase fast Fourier transform(APFFT)for simultaneous measurement of speed and *** offers superior accuracy in frequency determination by mitigating issues like the fence effect and spectrum leakage,contributing to the high-accuracy measurement for speed and *** simulations and experiments have demonstrated relative errors at the levels of 10^(−4) and 10^(−3) for distance and speed measurements,***,factors impacting measurement performance have been *** proposed method provides a high-performance and cost-effective solution for distance and speed measurements,applicable across scientific research and various industrial domains.

关键词： self-mixing interferometry frequency-modulated continuous-wave interferometry all-phase fast Fourier transform measurement of distance and speed.

High-performance and robust high-temperature polymer electrolyte membranes with moderate microphase separation by implementation of terphenyl-based polymers

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Journal of Energy Chemistry 2024年第5期92卷 572-578页

作者： jinyuan Li Congrong Yang Haojiang Lin Jicai Huang Suli Wang Gongquan Sun Division of Fuel Cells and Battery Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Laboratory of Fuel Cells&Hybrid Power Sources Chinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100039China

Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel *** overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the *** rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing *** a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer *** designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging *** a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel *** results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs.

关键词： Fuel cell High-temperature polymer electrolyte membranes Microphase separation Poly(terphenyl piperidinium)s Phosphoric acid

High-precision simulation and experimental verification of residual stress and surface topography of cylindrical surface shot peening

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 535-559页

作者： Zhao, Jiuyue Tang, jinyuan Liu, Huaming Zhang, Huiyun Li, Xin Ding, Han Cent South Univ State Key Lab Precis Mfg Extreme Serv Performance Changsha 410083 Peoples R China Cent South Univ Coll Mech & Elect Engn Changsha 410083 Peoples R China

Shot peening is commonly employed for surface deformation strengthening of cylindrical surface part. Therefore, it is critical to understand the effects of shot peening on residual stress and surface topography. Compared to flat surface, cylindrical surface shot peening has two significant features: (i) the curvature of the cylindrical surface and the scattering of the shot stream cause distributed impact velocities; (ii) the rotation of the part results in a periodic variation of the impact velocity component. Therefore, it is a challenge to quickly and accurately predict the shot peening residual stress and surface topography of cylindrical surface. This paper developed a high-precision model which considers the more realistic shot peening process. Firstly, a kinematic analysis model was developed to simulate the relative movement of numerous shots and cylindrical surface. Then, the spatial distribution and time-varying impact information was calculated. Subsequently, the impact information was used for finite element modeling to predict residual stress and surface topography. The proposed kinematic analysis method was validated by comparison with the discrete element method. Meanwhile, 9310 high strength steel rollers shot peening test verified the effectiveness of the model in predicting the residual stress and surface topography. In addition, the effects of air pressure and attack angle on the residual stress and surface topography were investigated. This work could provide a functional package for efficient prediction of the surface integrity and guide industrial application in cylindrical surface shot peening.

关键词： Shot peening Cylindrical surface 9310 high strength steel High-precision modeling Residual stress Surface topography FATIGUE BEHAVIOR ROUGHNESS INTEGRITY STRENGTH HARDNESS STEEL

Mechanism of capture section affecting an intake for atmosphere-breathing electric propulsion

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Chinese Journal of Aeronautics 2024年第1期37卷 51-63页

作者： Siyuan ZHANG jinyuan YANG Cheng LI Haolin LI Liwei ZHANG Liang DING Anbang SUN State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China China Academy of Aerospace Science and Innovation Beijing 100049China

Atmosphere-Breathing Electric Propulsion(ABEP)can compensate for lost momentum of spacecraft operating in Very Low Earth Orbit(VLEO)which has been widely concerned due to its excellent commercial *** is a key technology to improve the capture efficiency of intakes,which collect and compress the atmosphere for *** this paper,the mechanism of the capture section affecting capture efficiency is investigated by Test Particle Monte Carlo(TPMC)simulations with 3D intake *** inner surface smoothness and average collision number are determined to be key factors affecting capture efficiency,and a negative effect growth model is accordingly *** the inner surface smoothness is less than 0.2,the highest capture efficiency and its corresponding average collision number interval are independent of the capture section’s geometry and its mesh *** the inner surface smoothness is higher than 0.2,the capture efficiency will decrease by installing any capture *** on the present results,the manufacturing process and material selection are suggested to be prioritized during the intake geometry design in engineering ***,the highest capture efficiency can be achieved by adjusting the length and mesh size of the capture section.

关键词： Atmosphere-breathing electric propulsion Capture efficiency Capture section Intake Test particle Monte Carlo Very low earth orbit

Influence of nitrogen status on fermentation performances of non-Saccharomyces yeasts:a review

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Food Science and Human Wellness 2024年第2期13卷 556-567页

作者： Jinchen Li Mengmeng Yuan Nan Meng hehe Li jinyuan Sun Baoguo Sun Key Laboratory of Brewing Molecular Engineering of China Light Industry Beijing Key Laboratory of Flavor ChemistryBeijing Technology&Business UniversityBeijing 100048China

Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic *** influences are imposed on yeast growth and fermentation performances including the formation of secondary *** cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen *** the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being *** review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent *** discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final *** summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile *** gaps will therefore be elucidated for future research.

关键词： Non-Saccharomyces yeasts Nitrogen Fermentation kinetics Nitrogen preference Wine aroma

乡村振兴战略与林业经济发展研究——以辽宁省新宾县为例

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林业经济 2019年第6期41卷 117-122页

作者：何津源何君宁哲东北林业大学经济管理学院

文章收集、整理、归纳了辽宁省抚顺市新宾满族自治县林业发展情况,在国家实施乡村振兴战略的背景下,阐明了乡村振兴战略和林业经济发展的关系,分析了新宾县林业经济发展的现状和存在的问题,从提高林业产品深加工水平、引导林业企业进行... 详细信息

文章收集、整理、归纳了辽宁省抚顺市新宾满族自治县林业发展情况,在国家实施乡村振兴战略的背景下,阐明了乡村振兴战略和林业经济发展的关系,分析了新宾县林业经济发展的现状和存在的问题,从提高林业产品深加工水平、引导林业企业进行全面升级、规范林业企业会计工作运行、打通融资渠道、拓宽林权交易渠道、加快发展林下种养殖业及生态景区建设、继续优化林业产业结构体系7个方面提出了促进林业经济发展的具体对策,通过林业经济发展促进乡村振兴战略实施。

关键词：乡村振兴林业资源林业经济

An alternative approach to improve the compatibility of PCE in cement paste blend with coal gangue powder

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Waste Disposal and Sustainable Energy 2024年第1期6卷 139-150页

作者： Zonglin Xie Yuxuan Li Dahui Sun Yi Tian jinyuan Hu Qiang Yuan Zheng Chen School of Civil Engineering Central South UniversityChangshaChina China Railway NO.9 Group CO. LTDShenyangChina National Engineering Research Center for High-Speed Railway Construction Technology ChangshaChina Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanningChina

Coal gangue(CG)is an environmental waste that faces an urgent demand for disposal in *** utilization of CG in construction materials has broad application prospects and gained increasing ***,the poor compatibility of polycarboxylate superplasticizer(PCE)with CG powder hinders its efficiency in a wide range of ***,this paper attempts to improve the compatibility of PCE with CG powder in cement paste based on the regulation of aggregation and the adsorption behavior of *** light scattering(DLS)and fluorescence spectroscopy tests were carried out to understand the improved *** results indicated that the addition of CG powder increases the ionic strengths of the cement liquid phase,which makes PCE tend to aggregate at a lower concentration compared with no CG powder ***(CH_(3)COO)_(2)Cu is beneficial for enhancing the workability of cement paste by reducing PCE aggregation while maintaining the compressive strength of cement ***,(CH_(3)COO)_(2)Cu extra addition can be regarded as an effective and sustainable way to improve the workability of cement paste with CG powder.

关键词： Coal gangue powder Polycarboxylate superplasticizer Compatibility Aggregation