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Chinese Journal of Aeronautics 2024年第10期37卷 435-444页

作者： Qi zhong Junxian WANG Enguang XU Cheng YU Yanbiao li College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

Hydraulic circuits with high speed on/off valve(HSV)for servo control have become commonplace in ***,the individual valve that is not volume-optimized results in a large total size of hydraulic control system,diminishing the *** address this issue,the high-precision equivalent reluctance model of the HSV is established by employing an equivalent magnetic circuit,on which the dynamic characteristic of the HSV,as well as the effects of structural parameters on switching behaviour,are *** on this model,multi-objective optimization is adopted to design an HSV with faster dynamic performance and smaller volume,NSGA-II genetic algorithm is applied to obtain the Pareto front of the desired *** assess the impact before and after optimization,an HSV based on the optimized structure is manufactured and *** experimental results show that the optimized HSV reduces 47.1%of its solenoid volume while improving opening and closing dynamic performance by 14.8%and 43.0%respectively,increasing maximum switching frequency by 6.2%,and expanding flow linear control area by 6.7%.These results validate the optimized structure and indicate that the optimization method provided in the paper is beneficial for developing superior HSV.

关键词： High speed on/off valve Dynamic response Volume multiobjective optimization NSGA-II genetic algorithm

Stress corrosion cracking failure of X80 carbon steel U-b end cause d by Desulfovibrio vulgaris biocorrosion

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Journal of Materials Science & Technology 2024年第7期174卷 95-105页

作者： zhong li Jike Yang Shihang Lu Wenwen Dou Tingyue Gu Corrosion&Protection Center University of Science&Technology BeijingBeijing 100083China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China Department of Chemical and Biomolecular Engineering Institute for Corrosion and Multiphase TechnologyOhio UniversityAthensOH 45701USA

Sulfate reducing bacteria(SRB)are widely present in oil and gas industry,causing pitting corrosion on pipeline *** corrosion cracking(SCC)often occurs in the presence of mechanical stress before pit-ting perforation failure,leading to economic losses and even catastrophic *** this study,stress distribution simulation using the finite element method(FEM),corrosion analysis techniques and elec-trochemical corrosion measurements were employed to investigate the SCC mechanism of X80 pipeline steel caused by Desulfovibrio vulgaris,which is a common SRB strain used in microbiologically influenced corrosion(MIC)*** was found that *** MIC caused sharp microcracks on an X80 U-bend coupon after only 2 weeks of immersion at 37℃in the deoxygenated ATCC 1249 culture medium inocu-lated with *** X80 U-bend coupon’s weight loss-based uniform corrosion rate for the 12 cm^(2)surface was 60%of that for the unstressed flat square coupon(2.3 mg cm^(−2)vs.3.8 mg cm^(−2)).This was likely because the square coupon had wide MIC pits,providing a larger effective surface area for more sessile cells(4.2×10^(8)cells cm^(−2)on square coupon vs.2.4×10^(8)cells cm^(−2)on U-bend coupon)to attach and harvest more *** SCC failure occurred on an X80 U-bend pre-cracked at the outer bottom after a 6-week immersion in the *** *** from MIC damage,this could also be because *** metabolism increased the availability hydrogen atoms on the steel surface,and promoted the diffusion of hydrogen atoms into the metal lattice,thus increasing the brittleness of the steel.

关键词： Stress corrosion cracking Microbiologically influenced corrosion Sulfate reducing bacteria X80 U-bend steel Tensile stress

Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu LV Xiaohu GE Yi zhong Qiang li Yong XIAO School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

Functional Changes in Astrocytes Lead to Cognitive Deficits After Social Deprivation

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Neuroscience Bulletin 2024年第4期40卷 547-549页

作者： Yulan li lixuan li Yibei Wang Yi Wang zhong Chen Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhou310053China Department of Neurology Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou310009ZhejiangChina

Social experience has a far-reaching impact on the brain and *** humans,lacking social experience during childhood is associated with a faster decline in later-life cognitive function[l],while social isolation in the elderly is an independent risk factor for dementia[2].The lack of social experience at different stages of life has significant adverse effects on cognitive development and mental *** have largely been focused on the neuronal activity and synaptic plasticity changes after social *** recent studies separately reported increased expression of an astrocyte marker,glial fibrillary acidic protein,in socially isolated perinatal or adult mice demonstrating structural changes in astrocytes after social deprivation[3,4].However,it is still unknown whether and how astrocyte function is impacted by social deprivation.

关键词： faster function Functional

Potassium isotopic signatures of modern offshore detrital sediments from different climatic regimes and the implications

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Science China Earth Sciences 2024年第2期67卷 405-419页

作者： Jun mu Tianyu CHEN Qian YU Shichao AN Jianfang CHEN Xuefa SHI Weiqiang li State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Ministry of Education Key Laboratory for Coast and Island Development School of Geography and Ocean ScienceNanjing UniversityNanjing210023China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou310012China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao266061China

Potassium isotopes are a novel tracer for continental *** K isotope studies on chemical weathering generally targeted weathering profiles under a particular climate region,yet the effects of chemical weathering on K isotopes under different climatic backgrounds remain ***,little is known about the K isotope signatures of modern unconsolidated detrital ***,we report K isotopic data of surficial seafloor sediments from continental shelves along the east coast of China(ECC),as well as those around the tropical Hainan island in the northern South China *** ECC sediments have a relatively narrow distribution ofδ^(41)K(with reference to NIST3141a)values,which range from(-0.40±0.01)‰to(-0.57±0.04)‰,with an average of(-0.51±0.09)‰.By contrast,δ^(41)K values of Hainan offshore sediments display a larger variation,ranging from(-0.28±0.07)‰to(-0.67±0.02)‰.Theδ^(41)K values of Hainan offshore sediments exhibit negative correlations with the chemical index of alteration(CIA),Al/K,Ti/K,and total iron(FeT),which underlines the control of chemical weathering on K isotopic signatures of detritus inputs into *** also measured Mg isotope compositions for the same samples;interestingly,the variability inδ^(26)Mg of the samples is small(~0.24‰)for all ECC and Hainan offshore sediments,andδ^(26)Mg values do not show clear correlations with indexes of chemical *** study demonstrates the link between K isotopic variability of detrital sediments and climatic conditions including rainfall intensity,which indicates that K isotopes of the detrital component of marine sediments could be applied to study Earth’s climate in deep ***δ^(41)K values of the offshore detrital sediments are significantly less variable than those of pelagic marine sediments,highlighting the importance of distinguishing the effects of diagenesis and neoformation of clay minerals from continental weathering in attempts to study deep-time climate-weathering

关键词： Potassium isotopes Magnesium isotopes Chemical weathering Detrital sediments Climatic regimes Mean annual precipitation

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融合改进人工蜂群和K均值聚类的图像分割

液晶与显示 2017年第9期32卷 726-735页

作者：赵文昌李忠木大理大学工程学院云南大理671003

针对人工蜂群优化的K均值算法易陷入局部最优、搜索精度不够、分割图像不够细致等问题,本文融合自适应人工蜂群和K均值聚类,提出了一种新的图像分割算法。算法首先利用距离最大最小乘积对种群进行初始化;其次采用自适应搜索参数动态调... 详细信息

针对人工蜂群优化的K均值算法易陷入局部最优、搜索精度不够、分割图像不够细致等问题,本文融合自适应人工蜂群和K均值聚类,提出了一种新的图像分割算法。算法首先利用距离最大最小乘积对种群进行初始化;其次采用自适应搜索参数动态调整邻域搜索范围,使人工蜂群算法快速收敛于全局最优;然后将人工蜂群输出的所有蜜源进行K均值聚类,克服K均值聚类结果对初始聚类中心的依赖,再将聚类划分结果进行Powell局部搜索,加快算法收敛的速度,将得到的新聚类中心更新蜂群中蜜源位置。最后,将本文算法与其他两种同类分割算法进行试验对比。实验结果表明:与其他两种算法相比,本文提出的分割算法在保证运行时间的前提下,分割准确率比其他两种算法分别至少提高了3.5%和4.8%,表现出了较高的分割质量。

关键词：自适应人工蜂群 K均值聚类图像分割 Powell局部搜索距离最大最小乘积

Embracing digital mindsets to ensure a sustainable future

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 177-179页

作者： Chengjun li Riqing Yu Wenjing Ning Huan zhong Christian Sonne Institute of Environmental Research at Greater Bay Area Guangzhou UniversityGuangzhou 510000China Department of Biology Center for EnvironmentBiodiversity and ConservationThe University of Texas at TylerTylerTX 75701USA School of Environment Nanjing UniversityNanjing 210000China Environmental and life Science Program Trent UniversityPeterboroughOntarioK9H 0A1Canada Faculty of Science and Technology Aarhus UniversityRoskildeDenmark 4000The Kingdom of Denmark Sustainability Cluster School of EngineeringUniversity of Petroleum&Energy StudiesDehradunUttarakhand 248001India

The 19th Asian Games astounded global audiences with an opening spectacle that showcased stunning digital fireworks(International Olympic Committee,2021;Zhe,2023).The groundbreaking display was brought to life through virtual reality(VR)and augmented reality(AR)*** sets a pioneering example to replace conventional fireworks in major international events as well as in other large-scale entertainment activities,marking a historic milestone in the pursuit of a sustainable and healthy future.

关键词： Wildlife Climate Change Heavy metals Noise LAN light pollution

Effect of solvent on the initiation mechanism of living anionic polymerization of styrene:A computational study

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Chinese Journal of Chemical Engineering 2024年第5期69卷 135-142页

作者： Shen li Yin-Ning Zhou zhong-Xin liu Zheng-Hong Luo School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

For living anionic polymerization(LAP),solvent has a great influence on both reaction mechanism and *** this work,by using the classical butyl lithium-styrene polymerization as a model system,the effect of solvent on the mechanism and kinetics of LAP was revealed through a strategy combining density functional theory(DFT)calculations and kinetic *** terms of mechanism,it is found that the stronger the solvent polarity,the more electrons transfer from initiator to solvent through detailed energy decomposition analysis of electrostatic interactions between initiator and solvent ***,we also found that the stronger the solvent polarity,the higher the monomer initiation energy barrier and the smaller the initiation rate ***,initiation is more favorable at lower temperatures based on the calculated results ofΔG_(TS).Finally,the kinetic characteristics in different solvents were further examined by kinetic *** is found that in benzene and n-pentane,the polymerization rate exhibits first-order ***,slow initiation and fast propagation were observed in tetrahydrofuran(THF)due to the slow free ion formation rate,leading to a deviation from first-order kinetics.

关键词： living anionic polymerization Solvent effect Reaction kinetics Computational chemistry Mathematical modeling Kinetic modeling

Progress in processing of porous titanium:a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-li Yang Xian-Feng Du Zhi-lin Xu zhong-Shuai liang li-Long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of EducationSchool of ChemistryXi'an Jiaotong UniversityXi'an 710049China

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace,marine engineering and biomedical fields due to their high corrosion resistance,low density,good biocompatibility and excellent mechanical ***,in this paper,a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes)for fabricating porous titanium is firstly covered in terms of their working principles,capabilities,shortcomings and ***,the influencing factors of various methods on final pore structure of porous Ti are ***,a summary of the chemical methods(CM)to obtain the porous Ti is also provided,such as dealloying method and reduction ***,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Stable Cycling of All-Solid-State lithium Metal Batteries Enabled by Salt Engineering of PEO-Based Polymer Electrolytes

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Energy & Environmental Materials 2024年第2期7卷 67-74页

作者： Lujuan liu Tong Wang li Sun Tinglu Song Hao Yan Chunli li Daobin mu Jincheng Zheng Yang Dai Department of Chemical Engineering Shanghai UniversityShangda Road 99Shanghai 200444China School of Material Science&Engineering Beijing Key Laboratory of Environmental Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Physics Xiamen UniversityXiamen 361005China

Poly(ethylene oxide)(PEO)-based polymer electrolytes show the prospect in all-solid-state lithium metal batteries;however,they present limitations of low room-temperature ionic conductivity,and interfacial incompatibility with high voltage ***,a salt engineering of 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonimide lithium salt(liHFDF)/liTFSI system was developed in PEO-based electrolyte,demonstrating to effectively regulate li ion transport and improve the interfacial stability under high *** show,by manipulating the interaction between PEO matrix and TFSI^(-)-HFDF^(-),the optimized solid-state polymer electrolyte achieves maximum li+conduction of 1.24×10^(-4)S cm^(-1)at 40℃,which is almost 3 times of the ***,the optimized polymer electrolyte demonstrates outstanding stable cycling in the liFePO_(4)/li and liNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)/li(3.0-4.4 V,200 cycles)based all-solid-state lithium batteries at 40℃.

关键词： all-solid-state battery high voltage li-ion conductivity molecular interaction poly(ethylene oxide)