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Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei Xu Renke Kang Bi Zhang yuan Zhang Chenxu Wang yan bao Zhigang Dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding

A Modified Iterative Learning Control Approach for the Active Suppression of Rotor Vibration Induced by Coupled Unbalance and Misalignment

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 242-253页

作者： Yifan bao Jianfei Yao Fabrizio Scarpa yan Li College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of High-end Compressor and System Technology Beijing 100029China Beijing Key Laboratory of High-end Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Bristol Composites Institute(ACCIS) University of BristolBristol BS81TRUK Dynamics and Control Research Group(DCRG) University of BristolBristol BS81TRUK

This paper proposes a modified iterative learning control(MILC)periodical feedback-feedforward algorithm to reduce the vibration of a rotor caused by coupled unbalance and parallel *** control of the vibration of the rotor is provided by an active magnetic actuator(AMA).The iterative gain of the MILC algorithm here presented has a self-adjustment based on the magnitude of the *** filters are adopted to extract the synchronous(1×Ω)and twice rotational frequency(2×Ω)components of the rotor *** the notch frequency of the filter and the size of feedforward storage used during the experiment have a real-time adaptation to the rotational *** method proposed in this work can provide effective suppression of the vibration of the rotor in case of sudden changes or fluctuations of the rotor *** and experiments using the MILC algorithm proposed here are carried out and give evidence to the feasibility and robustness of the technique proposed.

关键词： Rotor vibration suppression Modified iterative learning control Unbalance Parallel misalignment Active magnetic actuator

Distributed phase-matching measurement for dynamic strain and temperature sensing based on stimulated Brillouin scattering enhanced four-wave mixing

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Photonics Research 2024年第1期12卷 141-153页

作者： yuan WANG PEDRO TOVAR JUNTONG yanG LIANG CHEN XIAOYI bao Nexus for Quantum Technologies University of OttawaOttawaOntario K1N 6N5Canada

A Brillouin dynamic grating(BDG) can be used for distributed birefringence measurement in optical fibers,offering high sensitivity and spatial resolution for sensing ***,it is quite a challenge to simultaneously achieve dynamic measurements with both high accuracy and high spatial *** this work,we propose a sensing mechanism to achieve distributed phase-matching measurement using a chirped pulse as a probe *** BDG reflection,the peak reflection corresponds to the highest four-wave mixing(FWM) conversion efficiency,and it requires the Brillouin frequency in the fast and slow axes to be equal,which is called the phase-matching *** condition changes at different fiber positions,which requires a range of frequency injection for the probe *** proposed method uses a chirped pulse as a probe wave to cover this frequency range associated with distributed birefringence *** allows us to detect distributed phase matching for birefringence changes that are introduced by temperature and strain *** to the single shot and direct time delay measurement capability,the acquisition rate in our system is only limited by the fiber ***,unlike conventional BDG spectrum recovery-based systems,the spatial resolution here is determined by both the frequency chirping rate of the probe pulse and the birefringence profile of the *** the experiments,an acquisition rate of 1 k Hz(up to fiber length limits) and a spatial resolution of 10 cm using a 20 ns probe pulse width are *** minimum detectable temperature and strain variation are 5.6 mK and 0.37 με along a 2 km long polarization-maintaining fiber(PMF).

关键词： fiber scattering polarization

Module Structures on U(ε^(-))for the Euclidean Algebra

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Algebra Colloquium 2024年第1期31卷 49-56页

作者： Yixin bao yan'an Cai School of Sciences Harbin Institute of Technology ShenzhenGuangdong 518055China Department of Mathematics Soochow University SuzhouJiangsu 215006China

We classify modules which are free of rank 1 when restricted to the negative part for the Euclidean Lie *** and necessary conditions for the simplicity of these modules are *** these modules we construct modules which... 详细信息

关键词： Euclidean algebra free module simple module nonweight module

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： Yong-Pan Duan Run-Qiang Chi bao-Jun Pang yuan Cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms

Distribution and geochemical significance of alkylbenzenes for crude oil with different depositional environments and thermal maturities

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Petroleum Science 2024年第2期21卷 777-790页

作者： Bing-Kun Meng Dao-Fu Song yuan Chen Sheng-bao Shi School of Petroleum Engineering and Environmental Engineering Yan'an UniversityYan'an716000ShaanxiChina State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing102249China

A total of 45 alkylbenzenes were detected and identified in crude oils with different depositional environments and thermal maturities from the Tarim Basin,Beibuwan Basin,and Songliao Basin using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry(GC×GCTOFMS).By analyzing the distribution characteristics of C0-C5alkylbenzenes,it is found that the content of some alkylbenzenes varies greatly in crude *** on the distribution characteristics of 1,2,4,5-tetramethylbenzene(Te MB)and 1,2,3,4-Te MB,the ratio of 1,2,4,5-Te MB to 1,2,3,4-Te MB is proposed to indicate the organic matter origin and depositional environment of ancient *** samples originated mainly from lower hydrobiont,algae,bacteria and source rocks deposited under reducing/anoxic conditions have low 1,2,4,5-/1,2,3,4-Te MB values(less than 0.6),while oil samples originated mainly from terrestrial higher plants and source rocks deposited under oxic/sub-oxic conditions have higher 1,2,4,5-/1,2,3,4-Te MB values(greater than 1.0).The significant difference of 1,2,4,5-/1,2,3,4-Te MB values is controlled by 1,2,4,5-Te MB content.1,2,4,5-Te MB content in oils derived from source rocks deposited in oxidized sedimentary environment(greater than 1.0 mg/g whole oil)is higher than that in oils from source rocks deposited in reduced sedimentary environment(less than 1.0 mg/g whole oil).1,2,4,5-/1,2,3,4-Te MB ratio might not or slightly be affected by evaporative fractionation,biodegradation and thermal maturity.1,2,4,5-/1,2,3,4-Te MB ratio and 1,2,4,5-Te MB content can be used as supplementary parameter for the identification of sedimentary environment and organic matter *** should be noted that compared to the identification of organic matter sources,the 1,2,4,5-/1,2,3,4-Te MB parameter is more effective in identifying sedimentary environments.

关键词： 1 2 4 5-Tetramethylbenzene GC×GC-TOFMS Organic matter origin Depositional environment

Multi-omics analyses provide insights into the evolutionary history and the synthesis of medicinal components of the Chinese wingnut

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Plant Diversity 2024年第3期46卷 309-320页

作者： Zi-yan Zhang He-Xiao Xia Meng-Jie yuan Feng Gao Wen-Hua bao Lan Jin Min Li Yong Li College of Life Science and Technology Inner Mongolia Normal UniversityHohhot 010020China Key Laboratory of Biodiversity Conservation and Sustainable Utilization in Mongolian Plateau for College and University of Inner Mongolia Autonomous Region Hohhot 010022China College of Landscape and Art Henan Agricultural UniversityZhengzhou 450002China State Key Laboratory of Tree Genetics and Breeding Chinese Academy of ForestryBeijing 100091China

Chinese wingnut(Pterocarya stenoptera)is a medicinally and economically important tree species within the family ***,the lack of high-quality reference genome has hindered its in-depth *** this study,we successfully assembled its chromosome-level genome and performed multiomics analyses to address its evolutionary history and synthesis of medicinal components.A thorough examination of genomes has uncovered a significant expansion in the Lateral Organ Boundaries Domain gene family among the winged group in *** notable increase may be attributed to their frequent exposure to flood-prone *** further differentiation between Chinese wingnut and Cyclocarya paliurus,significant positive selection occurred on the genes of NADH dehydrogenase related to mitochondrial aerobic respiration in Chinese wingnut,enhancing its ability to cope with waterlogging *** genomic analysis revealed Chinese wingnut evolved more unique genes related to arginine synthesis,potentially endowing it with a higher capacity to purify nutrient-rich water *** of terpene synthase families enables the production of increased quantities of terpenoid volatiles,potentially serving as an evolved defense mechanism against herbivorous *** combined transcriptomic and metabolomic analysis,we identified the candidate genes involved in the synthesis of terpenoid *** study offers essential genetic resources for Chinese wingnut,unveiling its evolutionary history and identifying key genes linked to the production of terpenoid volatiles.

关键词： Genome Medicinal components Metabolome Pterocarya stenoptera Transcriptome

A triboelectric nanogenerator based on a spiral rotating shaft for efficient marine energy harvesting of the hydrostatic pressure differential

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Materials Reports(Energy) 2024年第3期4卷 69-76页

作者： Xuemei Song yuan Chao Pan Chang bao Han Chang Xin Liu Yaxiaer Yalikun Hui yan yang yang Key Laboratory of Advanced Functional Materials(Beijing University of Technology) Ministry of EducationBeijing Key Lab of Microstructure and Property of Advanced MaterialsBeijing University of TechnologyBeijing100124PR China Institute of Deep-Sea Science and Engineering Chinese Academy of SciencesSanya572000PR China Division of Materials Science Nara Institute of Science and Technology8916-5 Takayama-choIkomaNara630-0192Japan

Equipment used in underwater sensing and exploration typically relies on cables or batteries for energy supply,resulting in a limited and inconvenient energy supply and marine environmental pollution that hinder the sustainable development of distributed ocean sensing ***,we design a deep-sea differential-pressure triboelectric nanogenerator(DP-TENG)based on a spiral shaft drive using modified polymer materials to harness the hydrostatic pressure gradient energy at varying ocean depths to power underwater *** spiral shaft structure converts a single compression into multiple rotations of the TENG rotor,achieving efficient conversion of differential pressure *** multi-pair electrode design enables the DP-TENG to generate a peak current of 61.7μA,the instantaneous current density can reach 0.69μA cm^(-2),and the output performance can be improved by optimizing the spiral angle of the *** DP-TENG can charge a 33μF capacitor to 17.5 V within five working *** can also power a digital calculator and light up 116 commercial power light-emitting diodes,demonstrating excellent output *** its simple structure,low production cost,and small form factor,the DP-TENG can be seamlessly integrated with underwater *** results hold broad prospects for underwater blue energy harvesting and are expected to contribute to the development of self-powered equipment toward emerging“smart ocean”and blue economy applications.

关键词： Triboelectric nanogenerators Blue energy Energy harvesting Differential pressure energy Self-power sensor

Deep electrical structures of Qinzhou-Fangcheng Junction Zone in Guangxi and seismogenic environment of the 1936 Lingshan M6^(3/4)earthquake

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Science China Earth Sciences 2024年第2期67卷 584-603页

作者： Bin ZHOU Chunheng yan yan ZHAN Xiangyu SUN Sha LI Xiang WEN Yajun MO Yongdong yuan yuan yuan Meili HUANG Earthquake Agency of Guangxi Zhuang Autonomous Region Nanning530022China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing100029China Guangxi Geophysical Survey Institute Liuzhou545005China

The tectonic position of the southwest section of the Qinzhou Bay-Hangzhou Bay Tectonic Junction Zone(QHTJZ)can be determined by examining the Qinzhou-Fangcheng Junction Zone(QFJZ)in *** zone is significant because it was the location of the largest earthquake ever recorded in the inland region of South China,specifically the 1936 Lingshan M6^(3/4)earthquake in ***,this region serves as an optimal location for researching the origins of intraplate earthquakes in South *** study presents a display of a broadband magnetotelluric(MT)prospecting profile that traverses the Guangxi QFJZ and the Lingshan earthquake zone,extending from the northwest(NW)to the southeast(SE).A resistivity structure model was generated using three-dimensional(3D)inversion technology along the *** main faults in QFJZ were analyzed in terms of their deep extension forms and tectonic *** analysis was performed by integrating the results obtained from geology,gravity,wave velocity ratio,Global Position System(GPS),and geothermal *** results showed that(1)the Dongzhong-Xiaodong fault(DXf),the eastern Fangcheng-Lingshan fault(FLf2),and the eastern Hepu-Beiliu fault(HBf2)were all trans-crustal deep faults,and crust-mantle ductile shear zones developed in the deep *** electrical boundary zones,DXf and HBf2,were *** inclined towards the northwest,while HBf2 inclined towards the *** FangchengLingshan fault(FLf)exhibits a tectonic style resembling a“flower”shape in the upper *** the deeper section,it is characterized by an electrical boundary zone that gradually slopes towards the southeast direction.(2)The Hunan-Guangxi Passive Continental Margin(HGPCM)on the NW side of DXf had a stratified resistivity structure and relatively stable Bouguer gravity anomalies,which conformed to the quasi-craton tectonic attribute of the local failure at the southeastern margin of the yangtze Block(YB).The southeastern side of this bloc

关键词： South China Block Qinzhou-Fangcheng Junction Zone Magnetotelluric 1936 Lingshan M6^(3/4)earthquake Deep seismogenic environment