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Data-Driven Active Disturbance Rejection Control of Plant-Protection Unmanned Ground Vehicle Prototype: A Fuzzy Indirect Iterative Learning Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1892-1894页

作者： Tao chen Ruiyuan Zhao jian chen Zichao Zhang College of Engineering China Agricultural UniversityBeijing 100083China Key Laboratory of Smart Agricultural Technology in Tropical South China Ministry of Agriculture and Rural AffairsGuangzhou 510642China

Dear Editor,This letter proposes a fuzzy indirect iterative learning(FIIL)active disturbance rejection control(ADRC)scheme to address the impact of uncertain factors of plant-protection unmanned ground vehicle(UGV),in which ADRC is a data-driven model-free control algorithm that only relies on the input and output data of the *** on the established nonlinear time-varying dynamic model including dynamic load(medicine box),the FIIL technology is adopted to turn the bandwidth and control channel gain online,in which the fuzzy logic system is used to update the gain parameters of iterative learning in real *** and experiment show the FIIL-ADRC scheme has better control performance.

关键词： Active scheme iterative

Charge transfer complex enabled photoreduction of ether phosphonium salts for the selective oxyalkylation of enamides

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Chinese Chemical Letters 2024年第2期35卷 411-414页

作者： Sen qiao Kunquan chen Qiang Liu Zhixiang Wang Xiangyu chen School of Chemical Sciences University of the Chinese Academy of SciencesBeijing 100049China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou 256606China

A charge transfer complex(CTC)-enabled photoreduction of ether phosphonium salts for the generation of oxyalkyl radicals was *** photoreduction provides a convenient method to achieve selective oxyalkylation of enamid... 详细信息

关键词： Enamides Phosphonium salts Ethers Charge transfer complex Visible light

A highly sensitive LITES sensor based on a multi-pass cell with dense spot pattern and a novel quartz tuning fork with low frequency

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Opto-Electronic Advances 2024年第3期7卷 26-34页

作者： Yahui Liu Shunda qiao Chao Fang Ying He Haiyue Sun jian Liu Yufei Ma National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150000China Zhengzhou Research Institute Harbin Institute of TechnologyZhengzhou 450000China Advanced Microscopy and Instrumentation Research Center School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China.

A highly sensitive light-induced thermoelectric spectroscopy(LITES)sensor based on a multi-pass cell(MPC)with dense spot pattern and a novel quartz tuning fork(QTF)with low resonance frequency is reported in this *** erbi-um-doped fiber amplifier(EDFA)was employed to amplify the output optical power so that the signal level was further *** optical path length(OPL)and the ratio of optical path length to volume(RLV)of the MPC is 37.7 m and 13.8 cm^(-2),respectively.A commercial QTF and a self-designed trapezoidal-tip QTF with low frequency of 9461.83 Hz were used as the detectors of the sensor,*** target gas selected to test the performance of the system was acetylene(C2H2).When the optical power was constant at 1000 mW,the minimum detection limit(MDL)of the C2H2-LITES sensor can be achieved 48.3 ppb when using the commercial QTF and 24.6 ppb when using the trapezoid-al-tip *** improvement of the detection performance by a factor of 1.96 was achieved after replacing the commer-cial QTF with the trapezoidal-tip QTF.

关键词： light-induced thermoelectric spectroscopy quartz tuning fork multi-pass cell gas sensing

Legacy and emerging per-and polyfluoroalkyl substances(PFAS) in the atmosphere: A comprehensive review

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Science China Technological Sciences 2024年第10期67卷 3032-3050页

作者： qiao BiTing SONG DongBao chen Hao YAO YiMing SUN HongWen MOE Key Laboratory of Pollution Processes and Environmental Criteria College of Environmental Science and EngineeringNankai University

With long-term production and widespread application, per-and polyfluoroalkyl substances(PFAS) have been detected in various media worldwide, including the atmosphere. Since the gradual restriction and phase-out of C8perfluoroalkyl acids(PFAAs), environmental contamination by emerging PFAS substitutes such as short-chain PFAA homologues, perfluoroether carboxylic, and sulfonic acids has been reported. Although there has been extensive monitoring of emerging PFAS substitutes in the aquatic environment, few studies have conducted target analysis and nontarget screening(NTS) of emerging unknown PFAS in the atmosphere over the past decade. To fill the gap, this review focused on emerging PFAS in the atmosphere in addition to legacy PFAS. The reported sampling, pretreatment, and instrumental analysis methods for target analysis and NTS of both neutral and ionic PFAS in the atmosphere are summarized, along with the advantages and current limitations of different sampling and NTS methods for PFAS in the atmosphere. The global levels, composition, and spatiotemporal distribution characteristics of legacy and emerging PFAS in the atmosphere are summarized and their transport, transformation, and dry/wet deposition are elucidated. The review highlights the importance of developing and applying the all-in-one strategy integrating target, suspect screening, and NTS to gain insights into emerging PFAS in the atmosphere and provide a reference for future research.

关键词： emerging PFAS atmosphere nontarget screening spatiotemporal distribution fate

Surface pollen and modern vegetation in Southern Xinjiang,China

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Science China Earth Sciences 2024年第2期67卷 510-530页

作者： Yun ZHANG Lixin chen Yaoyao XI Zhaochen KONG Xianguo qiao State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China School of Geosciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and vegetation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern Xinjiang(34°00’–43°00’N,74°00’–94°00’E)in China,with an elevation range of 888–4530 *** pollen and vegetation were studied in the northern region of the Kunlun Mountains and the southern region of the Tianshan *** results showed that the surface pollen assemblages on the southern slope of the Tianshan Mountains(3530–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,chenopodiaceae,and Ephedra *** surface pollen assemblages in the eastern Pamir Plateau(4530–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3548–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and chenopodiaceae *** geographic distribution of the surface pollen sites obtained using ArcGIS,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external origin and were transported by wind,water(rivers),and ice(glacier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strongly indicating the presence of local parent *** to the Hybrid Singleparticle Lagrangian Integrated Trajectory model,more Pinus pollen was transported to the Pamir region by external airflows during spring and summer,resulting in its higher surface pollen *** elucidating t

关键词： Surface pollen Vegetation Distribution Picea Southern Xinjiang

O_(2) adsorption on Fe_(3)O_(4) (110) surface and effect of gangue element Al doping: combined study of binding experiment and ab initio molecular dynamics

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Journal of Iron and Steel Research International 2024年第4期31卷 810-827页

作者： Zheng-jian Liu Hui-qing jiang Yao-zu Wang jian-liang Zhang Hong-mei qiao An-yang Zheng Fang-yu Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Beijing Shougang Co. Ltd.Qian'an 064404HebeiChina Department of Physics National University of Defense TechnologyChangsha 410128HunanChina

At high temperature,the chemical reaction mechanism at the interface of magnetite and the influence mechanism of gangue element Al on the oxidation performance of magnetite are not *** addition,due to the limitation of existing experimental equipment,it is difficult to clarify the interface reaction mechanism in the oxidation process and the influence mechanism of Al on the surface oxidation reaction of Fe_(3)O_(4) at an atomic scale at high *** surface oxidation reaction mechanism of magnetite and the influence mechanism of Al on the oxidation of magnetite were studied by experiments and AIMD(ab initio molecular dynamics).The experimental results show that the existence of Al_(2)O_(3) will reduce the initial oxidation temperature and comprehensive oxidation performance of *** AIMD results show that aluminum can accelerate the interface reaction rate of Fe_(3)O_(4) in the high-temperature oxidation atmosphere,but the strong Al-O binding ability is not conducive to the transfer of O atoms in the oxidation process.

关键词： Ironmaking Magnetite oxidation Interface reaction Adsorption-Gangue aluminum AIMD

Atomistic study of inverse size effect induced by interfacial plasticity in pearlitic multi-principal element alloy

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Rare Metals 2024年第7期43卷 3341-3355页

作者： chen Yang qiao-Sheng Xia Cun-Hong Yin Dong-Peng Hua College of Mechanical Engineering Guizhou UniversityGuiyang 550025China Key Laboratory of Advanced Manufacturing Technology Ministry of EducationGuizhou UniversityGuiyang 550025China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi'an 710072China

Owing to the fine nano-laminated structure,the pearlitic multi-principal element alloy(PMPEA) exhibits excellent mechanical and tribological ***,the incomplete understanding of the size effect of its lamella thickness and the unclear understanding of the plasticity-interface interaction mechanism limit further optimization of *** this study,the FeCoNi/Ni_3Ti interface-mediated plastic deformation behavior in PMPEA and the variation of mechanical and tribological properties with lamella thickness within the nanoscale range using molecular dynamics(MD) simulation were *** results indicate that the mechanical and tribological properties of the PMPEA with lamella thicknesses below 10 nm have a significant inverse size effect,i.e.,the smaller the lamella thickness,the weaker the *** is because the plastic carrier-interface interaction mechanism changes from a strengthening mechanism that hinders dislocations to a weakening mechanism that promotes dislocations with the decreases in the lamella thickness,and the weakening effect becomes more pronounced as the lamella thickness decreases and the number of interfaces *** particular,the deformation behavior of Ni_3Ti lamellae changes from crystal-like to amorphous-like with decreasing ***,in the sample with larger lamella thickness,the occurrence of hierarchical slips in the body-centered cubic(BCC) phase due to the multiprincipal elements effect can better alleviate the stress concentration caused by the dislocation accumulation at the interface,so that the phase interface exhibits outstanding load-bearing *** the dislocation pattern in BCC phase shows a firm high-density cell,which makes the substrate exhibit a stable tribological response.

关键词： Multi-principal element alloy Nano-laminated structure Molecular dynamics simulation Nanoindentation and nanoscratch

Reshaping force for deformed casing repairing with hydraulic rolling reshaper and its influencing factors

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Petroleum Science 2024年第4期21卷 2745-2757页

作者： Hong-Fei Li Min Luo Ting-Ting Xu qiao-Zhen Li Cong-jian Huang School of Mechanical Science and Engineering Northeast Petroleum University

Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years. When it is used for well repair operation, the reshaping force provided by ground devices is generally determined by experience. However, too large reshaping force may destroy the deformed casing, and too small reshaping force may also prolong the construction period and affect the repairing effect. In this paper, based on Hertz contact theory and elastic-plastic theory, combined with the process parameters of shaping, and considering the structural characteristics of the deformed casing and reshaper, we propose a mathematical model for calculating the reshaping force required for repairing deformed casing by hydraulic rolling reshaper. Meanwhile, the finite element model and numerical method of hydraulic rolling reshaper repairing deformed casing are established by using the finite element method, and the reliability of the mathematical model is verified by several examples. On this basis, the control variable method is used to investigate the influence of each parameter on the reshaping force, and the influence degree of each parameter is explored by orthogonal simulation test and Pearson correlation analysis. The research results not only provide an important theoretical basis for the prediction of reshaping force in on-site construction, but also provide a reference for the subsequent improvement of the shaping process.

关键词： Hydraulic rolling reshaper Reshaping force Deformed casing Casing reshaping Hertz contact theory

Generalized Inverses and Units in a Unitary Ring

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1000-1014页

作者： Yu Kun ZHOU jian Long chen School of Mathematics Southeast UniversityNanjing 210096P.R.China

Let R be a unitary ring and a,b∈R with ab=*** find the 2/3 property of Drazin invertibility:if any two of a,b and a+b are Drazin invertible,then so is the third ***,we combine the 2/3 property of Drazin invertibility to characterize the existence of generalized inverses by means of *** applications,the need for two invertible morphisms used by You and chen to characterize the group invertibility of a sum of morphisms is reduced to that for one invertible morphism,and the existence and expression of the inverse along a product of two regular elements are obtained,which generalizes the main result of Mary and Patricio(2016)about the group inverse of a product.

关键词： Leftπ-regular element stronglyπ-regular element group inverse Drazin inverse inverse along an element