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Nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in aerospace community:a comparative analysis

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International Journal of Extreme Manufacturing 2024年第2期6卷 190-271页

作者： Guolong zhao Biao zhao Wenfeng Ding Lianjia Xin Zhiwen Nian Jianhao Peng Ning He Jiuhua xu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

The aerospace community widely uses difficult-to-cut materials,such as titanium alloys,high-temperature alloys,metal/ceramic/polymer matrix composites,hard and brittle materials,and geometrically complex components,such as thin-walled structures,microchannels,and complex *** machining is the main material removal process for the vast majority of aerospace ***,many problems exist,including severe and rapid tool wear,low machining efficiency,and poor surface *** energy-assisted mechanical machining is a hybrid process that uses nontraditional energies(vibration,laser,electricity,etc)to improve the machinability of local materials and decrease the burden of mechanical *** provides a feasible and promising method to improve the material removal rate and surface quality,reduce process forces,and prolong tool ***,systematic reviews of this technology are lacking with respect to the current research status and development *** paper reviews the recent progress in the nontraditional energy-assisted mechanical machining of difficult-to-cut materials and components in the aerospace *** addition,this paper focuses on the processing principles,material responses under nontraditional energy,resultant forces and temperatures,material removal mechanisms,and applications of these processes,including vibration-,laser-,electric-,magnetic-,chemical-,advanced coolant-,and hybrid nontraditional energy-assisted mechanical ***,a comprehensive summary of the principles,advantages,and limitations of each hybrid process is provided,and future perspectives on forward design,device development,and sustainability of nontraditional energy-assisted mechanical machining processes are discussed.

关键词： difficult-to-cut materials geometrically complex components nontraditional energy mechanical machining aerospace community

Upconversion-based chiral nanoprobe for highly selective dual-mode sensing and bioimaging of hydrogen sulfide in vitro and in vivo

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Light(Science & Applications) 2024年第9期13卷 1878-1887页

作者： Yang Lu xu zhao Dongmei Yan Yingqian Mi Peng Sun xu Yan Xiaomin Liu Geyu Lu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University130012 ChangchunChina Department of Immunology College of Basic Medical SciencesJilin University130021 ChangchunChina

Chiral assemblies have become one of the most active research areas due to their versatility,playing an increasingly important role in bio-detection,imaging and *** this work,chiral UCNPs/CuxOS@ZIF nanoprobes are prepared by encapsulating upconversion nanoparticles(UCNPs)and CuxOS nanoparticles(NPs)into zeolitic imidazolate framework-8(ZIF-8).The novel excited-state energy distribution-modulated upconversion nanostructure(NaYbF4@-NaYF4:Yb,Er)is selected as the fluorescence source and energy donor for highly efficient fluorescence resonance energy transfer(FRET).CuxOS NP is employed as chiral source and energy acceptor to quench upconversion luminescence(UCL)and provide circular dichroism(CD)*** the natural adsorption and sorting advantages of ZIF-8,the designed nanoprobe can isolate the influence of other common disruptors,thus achieve ultra-sensitive and highly selective UCL/CD dual-mode quantification of H2S in aqueous solution and in living ***,the nanoprobe is also capable of in vivo intra-tumoral H2S *** work highlights the multifunctional properties of chiral nanocomposites in sensing and opens a new vision and idea for the preparation and application of chiral nanomaterials in biomedical and biological analysis.

关键词： chiral sulfide donor

Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

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Nuclear Science and Techniques 2024年第2期35卷 103-109页

作者： Jie zhao Jin-Hui Chen xu-Guang Huang Yu-Gang Ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200438China

Ultra-peripheral heavy-ion collisions(UPCs)offer unique opportunities to study processes under strong electromagnetic *** these collisions,highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon *** exchange of photons can induce photonuclear and two-photon interactions and excite *** excitation of the ions results in Coulomb dissociation with the emission of photons,neutrons,and other ***,the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ***,the two colliding ions experience an electromagnetic force that pushes them in opposite directions,causing a back-to-back correlation in the emitted *** a Monte Carlo simulation,we qualitatively demonstrate that the above electromagnetic effect is large enough to be observed in UPCs,which would provide a clear means to study strong electromagnetic fields and their effects.

关键词： Electromagnetic fields Neutrons Ultra-peripheral relativistic heavy-ion collisions(UPC)

The Application of Artificial Intelligence in Alzheimer’s Research

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Tsinghua Science and Technology 2024年第1期29卷 13-33页

作者： Qing zhao Hanrui xu Jianqiang Li Faheem Akhtar Rajput Liyan Qiao Faculty of Information Technology Beijing University of TechnologyBeijing 100124China School of Medicine Tsinghua UniversityBeijing 100084China Department of Computer Science Sukkur IBA UniversitySukkur 65200Pakistan Department of Neurology Tsinghua University Yuquan HospitalBeijing 100040China

Alzheimer's disease(AD)is an irreversible and neurodegenerative disease that slowly impairs memory and neurocognitive function,but the etiology of AD is still *** the explosive growth of electronic health data,the application of artificial inteligence(Al)in the healthcare setting provides excellent potential for exploring etiology and personalized treatment approaches,and improving the disease's diagnostic and prognostic *** paper first briefly introduces Al technologies and applications in medicine,and then presents a comprehensive review of Al in *** simple,it includes etiology discovery based on genetic data,computer-aided diagnosis(CAD),computer-aided prognosis(CAP)of AD using multi-modality data(genetic,neuroimaging and linguistic data),and pharmacological or non-pharmacological approaches for treating ***,some popular publicly available AD datasets are introduced,which are important for advancing Al technologies in AD ***,core research challenges and future research directions are discussed.

关键词： Alzheimer's disease artificial intelligence etiology discovery computer-aided diagnosis computer-aided prognosis treatment

Applying deep learning technique to chiral magnetic wave search

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Chinese Physics C 2024年第8期48卷 170-176页

作者： Yuan-sheng zhao xu-Guang Huang Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics National Natural Science Foundation of China and Fudan UniversityShanghai 200438China

The chiral magnetic wave(CMW)is a collective mode in quark-gluon plasma originated from the chiral magnetic effect(CME)and chiral separation *** detection in heavy-ion collisions is challenging owing to significant background ***[*** et al.,***.C 106,L051901(2022)],we constructed a neural network that accurately identifies the CME-related signal from the final-state pion *** this study,we have generalized this neural network to the case of CMW *** show that,after an updated training,the neural network effectively recognizes the CMW-related ***,we have assessed the performance of the neural network in comparison with other known methods for CMW search.

关键词： deep learning chiral magnetic wave relativistic heavy-ion collisions

Fully Decoupled Branch Energy Balancing Control Method for Modular Multilevel Matrix Converter Based on Sequence Circulating Components

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 235-247页

作者： Zexin zhao Weijiang Chen Zhichang Yang Guoliang zhao Bin Han Yunfei xu Nianwen Xiang Shulai Wang China Electric Power Research Institute Beijing 100192China State Grid Corporation of China Beijing 100031China State Grid Smart Grid Research Institute Beijing 102209China State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research InstituteBeijing 102211China Hefei University of Technology Hefei 230009China

The modular multilevel matrix converter(M3C)is a potential frequency converter for low-frequency AC ***,capacitor voltage control of high-voltage and largecapacity M3C is more difficult,especially for voltage balancing between *** solve this problem,this paper defines sequence circulating components and theoretically analyzes the influence mechanism of different sequence circulating components on branch capacitor voltage.A fully decoupled branch energy balancing control method based on four groups of sequence circulating components is *** method can control capacitor voltages of nine branches in horizontal,vertical and diagonal *** influences of both circulating current and voltage,a cross decoupled control is designed to improve control *** results are taken from a low-frequency transmission system based on PSCAD/EMTDC,and effectiveness and precision of the proposed branch energy balancing control method are verified in the case of nonuniform parameters and an unbalanced power system.

关键词： Branch energy balancing control decoupled control low-frequency AC transmission modular multilevel matrix converter(M3C) sequence circulating components

Reasonable grazing may balance the conflict between grassland utilization and soil conservation in the semi-arid hilly areas, China

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Journal of Arid Land 2024年第8期16卷 1130-1146页

作者： SUN Hui zhao Yunge GAO Liqian xu Mingxiang College of Forestry Northwest A&F UniversityYangling 712100China College of Soil and Water Conservation Science and Engineering Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Soil erosion caused by unsustainable grazing is a major driver of grassland ecosystem degradation in many semi-arid hilly areas in ***,grazing exclusion is considered as an effective method for solving this issue in such ***,some ecological and economic problems,such as slow grassland rejuvenation and limited economic conditions,have become obstacles for the sustainable utilization of grassland ***,we hypothesized that the conflict between grassland use and soil conservation may be balanced by a reasonable grazing *** this study,a two-year grazing fence experiment with five grazing intensity gradients was conducted in a typical grassland of the Loess Plateau in China to evaluate the responses of vegetation characteristics and soil and water losses to grazing *** five grazing intensity gradients were 2.2,3.0,4.2,6.7,and 16.7 goats/hm2,which were represented by G1-G5,respectively,and no grazing was used as *** results showed that a reasonable grazing intensity was conducive to the sustainable utilization of grassland *** biomass under G1-G4 grazing intensity significantly increased by 51.9%,42.1%,36.9%,and 36.7%,respectively,compared with *** addition,vegetation coverage increased by 19.6%under G1 grazing *** diversity showed a single peak trend with increasing grazing *** Shannon-Wiener diversity index under G1-G4 grazing intensities significantly increased by 22.8%,22.5%,13.3%,and 8.3%,respectively,compared with ***,grazing increased the risk of soil *** with control,runoff yields under G1-G5 grazing intensities increased by 1.4,2.6,2.8,4.3,and 3.9 times,respectively,and sediment yields under G1-G5 grazing intensities were 3.0,13.0,20.8,34.3,and 37.7 times greater,respectively,than those under *** result was mainly attributed to a visible decrease in litter biomass after grazing,which decreased by 50.5%,72.6%,79.0%,80.0%

关键词： fence-controlled grazing rehabilitated grassland vegetation community characteristics soil erosion sediment biocrusts Loess Plateau

Cation-Dipole Interaction-Induced Coacervate Underwater Adhesives in Natural Seawater

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Chinese Journal of Polymer Science 2024年第7期42卷 984-991,I0009页

作者： xu-Fei Liu Chong-Rui Zhang Hua-Wen Peng Qiang zhao Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Significant progress has been made in wet adhesives for low salinity water,but exploration of general ionic adhesives for natural seawater is less developed because the high salinity could weaken interfacial bonding and shields electrostatic interactions,resulting in adhesion ***,the design of adhesives for natural seawater represents challenges less ***,a cationic polyelectrolyte(PECHIA)containing imidazolacetonitrile unit was explored to prepare adhesives enabled by natural *** combining the ion shielding effect with the“cation-dipole”interactions between PECHIA chains,aqueous solution of the PECHIA underwent coacervation and self-crosslinking in natural seawater,allowing for underwater adhesion to various substrates in *** instantaneous lap-shear and tensile adhesion strengths are 47 and 119 kPa,respectively,while the cured adhesive shows~739 k Pa tensile adhesion in natural *** design of PECHIA enables wet adhesives viable for applications in the diversified scenarios of natural seawater.

关键词： Coacervate Underwater adhesives Seawater Cation-dipole interaction

Functional prediction of tomato PLATZ family members and functional verification of Sl PLATZ17

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Journal of Integrative Agriculture 2024年第1期23卷 141-154页

作者： Min xu zhao Gao Dalong Li Chen Zhang Yuqi Zhang Qian He Yingbin Qi He Zhang Jingbin Jiang Xiangyang xu Tingting zhao College of Horticulture and Landscape Architecture Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Northeast Region) Ministry of Agriculture and Rural AffairsHarbin 150030China

PLATZ is a novel zinc finger DNA-binding protein that plays an important role in regulating plant growth and development and resisting abiotic ***,there has been very little research on the function of this family gene in tomatoes,which limits its application in germplasm resource ***,the PLATZ gene family was identified and analyzed in tomato,and its roles were predicted and verified to provide a basis for in-depth research on SlPLATZ gene *** this study,the PLATZ family members of tomato were identified in the whole genome,and 19 SlPLATZ genes were *** prediction was conducted based on gene and promoter structure analysis and RNA-seq-based expression pattern *** genes that responded significantly under different abiotic stresses or were significantly differentially expressed among multiple tissues were screened as functional gene ***17 was selected for functional verification by experiment-based *** results showed that the downregulation of SlPLATZ17 gene expression reduced the drought and salt tolerance of tomato *** plants overexpressing SlPLATZ17 had larger flower sizes and long,thin petals,adjacent petals were not connected at the base,and the stamen circumference was *** study contributes to understanding the functions of the SlPLATZ family in tomato and provides a reference for functional gene screening.

关键词： tomato PLATZ family abiotic stresses plant development