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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin Hu Jun Cheng Zheng-Guang wu Huaicheng yan IEEE Zhejiang University of Technology Guangxi Normal University Zhejiang University the East China University of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

Comparison of Rotating Stall Warning by Different Methods for Variable Speed Configurations in a Contra-Rotating Compressor

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Journal of Thermal Science 2024年第4期33卷 1379-1393页

作者： XUE Fei WANG yan'gang LIU Qian wu Tong LIU Hanru School of Power and Energy Northwestern Polytechnical UniversityXi’an710072China

Stall in compressors can cause performance degradation and even lead to *** unacceptable consequences can be avoided by timely monitoring stall inception and taking effective *** paper focused on the rotating stall warning in a low-speed axial contra-rotating ***,the stall disturbance characteristics under different speed configurations were *** results showed that as the speed ratio(RR)increased,the stall disturbance propagation speed based on the rear rotor speed gradually ***,the standard deviation(SD)method,the cross-correlation(CC)method,and the discrete wavelet transform(DWT)method were employed to obtain the stall initiation moments of three different speed *** was found that the SD and CC methods did not achieve significant stall warning results in all three speed ***,the stall initiation moment obtained by the DWT method at RR=1.125 was one period after the stall had fully developed,which was ***,a stall warning method was developed in the present work based on the long short-term memory(LSTM)regression *** applying the LSTM model,the predicted stall initiation moments of three speed configurations were at the 557th,518th,and 333rd revolution,which were44,2,and 74 revolutions ahead of stall onset moments,***,in scenarios where a minor disturbance preceded the stall,the stall warning effect of the LSTM was greatly improved in comparison with the aforementioned three *** contrast,when the pressure fluctuation before the stall was relatively small,the differences between the stall initiation moments predicted by these four methods were not significant.

关键词： contra-rotating compressor stall disturbance stall initiation moment long short-term memory(LSTM) stall warning

Dynamic emission characteristics and control strategies of air pollutants from motor vehicles in downtown Beijing,China

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Journal of Environmental Sciences 2024年第2期136卷 637-646页

作者： yan Shen Tongran wu Aiping Lian Jie Gao Fei Peng Guohua Song Xuefang wu yangyang Cui Xinyu Liu Yunfei Wan Jing yan Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Municipal Ecology and Environment Bureau Beijing 100048China Beijing Jiaotong University Beijing 100091China

This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution *** results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle *** data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National V"or higher emission ***,to achieve higher air quality goals,further reducing vehicle emissions is *** on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(VOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle *** a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.

关键词： Motor vehicle Air pollutant Emission characteristics Control strategy Beijing

Attributes of Specialized Households'Resilience and Its Impact on Rural Industrial Advancement:A Case Study of National Musical Instrument Production Specialized Households in Lankao County,Henan,China

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Chinese Geographical Science 2024年第3期34卷 383-400页

作者： wu Nalin WEI Yike FAN Sizhe LI Li SUN Yufan ZHANG yan SHU yan Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of Educa-tion/The College of Geography and Environmental ScienceHenan UniversityKaifeng 475001China College of Urban and Envir-onmental Science Central China Normal UniversityWuhan 430079China Key Laboratory of Ecosystem Network Observation and Modelling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Specialized households serve as the primary units within specialized villages in China,and their capacity to withstand risks and external influences significantly shapes the future trajectory of specialized villages and the overall vitality of the rural *** this study,we established a measurement indicator system based on the definition of specialized households’resilience,elucidating the logical connection between specialized households’resilience and rural industrial development in *** musical instrument industry in Lankao County,Henan Province of China,was employed as a case;survey data,the entropy method,and an obstacle diagnosis model were used to examine how instrument production specialized households responded to the challenges posed by Corona Virus Disease 2019(COVID-19)and the tightening of national environmental protection policies,yielding the following key findings:1)there exists substantial variation in the comprehensive resilience levels among different specialized households;2)the ability to learn and adapt is the most significant contributor to the overall resilience level of specialized households;3)technological proficiency and access to skilled talent emerge as pivotal factors influencing specialized households’resilience;4)the positioning of specialized households within the industrial supply chain and the stability of their income have a direct bearing on their resilience *** influence of specialized households’resilience on industrial development primarily manifests in the following ways:stronger resilience correlates with increased stability in production and sales,fostering a more proactive approach to future ***,heightened exposure to the external macroeconomic environment can lead to a higher rate of export *** enhance the development resilience of entities like specialized households and family farms,and to invigorate rural economic development,escalating investments in rural science and technology

关键词： resilience specialized households rural industry Lankao County,China

Configuring single-layer MXene nanosheet onto natural wood fiber via C-Ti-C covalent bonds for high-stability Li-S batteries

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Journal of Energy Chemistry 2024年第8期95卷 701-711,I0016页

作者： yangyang Chen Yu Liao Ying wu Lei Li Zhen Zhang Sha Luo Yiqiang wu yan Qing College of Materials Science and Technology Central South University of Forestry and TechnologyChangsha 410004HunanChina

Lithium-sulfur batteries(LSBs)are considered promising candidates for next-generation battery technologies owing to their outstanding theoretical energy density and ***,the low conductivity and polysulfide shuttling effect of S cathodes severely hamper the practical performance of ***,in situ-generated single layer MXene nanosheet/hierarchical porous carbonized wood fiber(MX/PCWF)composites are prepared via a nonhazardous eutectic activation strategy coupled with pyrolysis-induced gas *** unique architecture,wherein single layer MXene nanosheets are constructed on carbonized wood fiber walls,ensures rapid polysulfide conversion and continuous electron transfer for redox *** C-Ti-C bonds formed between MXene and PCWF can considerably expedite the conversion of polysulfides,effectively suppressing the shuttle *** impressive capacity of 1301.1 m A h g^(-1)at 0.5 C accompanied by remarkable stability is attained with the MX/PCWF host,as evidenced by the capacity maintenance of 722.6 m A h g^(-1)after 500 ***,the MX/PCWF/S cathode can still deliver a high capacity of 886.8 m A h g^(-1)at a high S loading of 5.6 mg cm^(-2).The construction of two-dimensional MXenes on natural wood fiber walls offers a competitive edge over S-based cathode materials and demonstrates a novel strategy for developing high-performance batteries.

关键词： Lithium-sulfur batteries S cathodes MXene nanosheets Wood fiber C-Ti-C bonds

Lamellar quasi-solid electrolyte with nanoconfined deep eutectic solvent for high-performance lithium battery

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Nano Research 2024年第7期17卷 6176-6183页

作者： Shiwei Liu Jing Wang Keqi wu Zhirong yang yan Dai Junmei Zhang Wenjia wu Jingtao Wang School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China

Electrolytes with high-efficiency lithium-ion transfer and reliable safety are of great importance for lithium *** having superior ionic conductivity(10^(−3)–10^(−2) S·cm^(−1)),traditional liquid-state electrolytes always suffer from low lithium-ion transference number(tLi+sent liquid/quasi-solid *** addition,Vr-DES QSE shows significantly improved interfacial stability with Li anode as compared with *** assembled Li symmetric cell can operate stably for 1000 h at 0.1 mA·cm^(−2).The lithium iron phosphate(LFP)|Vr-DES QSE|Li cell exhibits high capacity of 142.1 mAh·g^(−1)after 200 cycles at 25℃ and 0.5 C,with a capacity retention of 94.5%.The strategy of open solvation shell through nanoconfinement effect of lamellar framework may shed light on the development of advanced electrolytes.

关键词： quasi-solid electrolyte deep eutectic solvent lamellar structure lithium-ion transference number solvation shell

Transition-Metal-Free Allylic Defluorination Cross-Electrophile Coupling Employing Rongalite

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Chinese Journal of Chemistry 2024年第12期42卷 1360-1366页

作者： Xiang-Long Chen Chun-yan wu Dong-Sheng yang Bo-Cheng Tang Huai-Yu Wang Zhi-Cheng Yu Anling Li yan-Dong wu An-Xin wu National Key Laboratory of Green Pesticide International Joint Research Center for Intelligent Biosensor Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhanHubei 430079China state Key Laboratory of Chemical Biology and Drug Discovery Department of Applied Biology and Chemical Technology The HongKong Polytechnic UniversityKowloonHong Kong SARChina Department of Clinical Laboratory Center for Gene Diagnosisand Program of Clinical Laboratory MedicineZhongnan Hospital of Wuhan UniversityWuhanHubei 430062China

Comprehensive Summary The conversion of CF3-alkenes to gem-difluoroalkenes using reductive cross-coupling strategy has received much attention in recent years,however,the use of green and readily available reducing salt to mediate these reactions remains to be *** this work,a concise construction of gem-difluoroalkenes,which requires neither a catalyst nor a metal reducing agent,was ***,a safe and inexpensive industrial product,was employed as both a radical initiator and *** procedure was compatible with both linear and cyclic diaryliodonium salts,enabling a wide variety of substrates(>70 examples).The utility of this approach was demonstrated through gram-scale synthesis and efficient late-stage functionalizations of anti-inflammatory drugs.

关键词： Defluoroarylation Transition metal free gem-Difluoroalkenes Rongalite Single electron transfer C-C coupling Redox reactions Cross-coupling

Microstructure and water-swelling mechanism of red-bed mudstone in the Xining region,Northeastern Tibetan Plateau

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2537-2551页

作者： Huan Guan Yong Ren Sixiang Ling Xiyong wu Tao Yu Xian Li sen Wang Chunwei Sun School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu611756China Moe Key Laboratory of High-speed Railway Engineering Southwest Jiaotong UniversityChengdu610031China Guangzhou Metro Design and Research Institute Co Ltd. Guangzhou510010China Chengdu City Construction Investment Group Co Ltd. Chengdu610036China

This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plateau.A series of laboratory tests,including swelling experiments,X-ray diffraction(XRD),and scanning electron microscope(SEM),was carried out for mechanical and microstructural *** coupled influence of the EC and microstructural parameters on the expansion ratio and pressure was investigated,and the weight coefficients were discussed by the entropy weight *** results revealed an increasing exponential trend in EC,and the maximum swelling speed occurred at an EC of approximately 10 μS/*** addition,a method for predicting the expansion potential is proposed based on the microstructure,and its reliability is verified by comparing with swelling experimental *** addition,according to the image analysis results,the ranges of the change in the clay minerals content(CMC),the fractal dimension(FD),the average diameter(AD)of pores,and the plane porosity(PP)are 23.75%-53%,1.08-1.17,7.53-22.45 mm,and 0.62%-1.25%,***,mudstone swelling is negatively correlated with the plane porosity,fractal dimension and average diameter and is linearly correlated with the clay mineral ***,the weight values prove that the microstructural characteristics,including FD,AD,and PP,are the main factors influencing the expansion properties of red-bed mudstones in the Xining *** on the combination of macro and micro-analyses,a quantitative analysis of the swelling process of mudstones can provide a better reference for understanding the mechanism of expansion behavior.

关键词： Mudstones Microstructure Swelling characteristics Electrical conductivity(EC) Scanning electron microscope Water-swelling

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang Liu Hong-wu Tang Sai-yu Yuan Jing yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

Dynamic gut microbiome-metabolome in cationic bovine serum albumin induced experimental immune-complex glomerulonephritis and effect of losartan and mycophenolate mofetil on microbiota modulation

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Journal of Pharmaceutical Analysis 2024年第4期14卷 562-577页

作者： Wenying Shi Zhaojun Li Weida Wang Xikun Liu Haijie wu Xiaoguang Chen Xunrong Zhou sen Zhang State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing100050China State Key Laboratory of Functions and Applications of Medicinal Plants College of PharmacyGuizhou Provincial Engineering Technology Research Center for Chemical Drug R&DGuizhou Medical UniversityGuiyang550004China Department of Medicine Solna Center for Molecular MedicineKarolinska University Hospital and Karolinska InstituteStockholm17176Sweden Department of Pharmacy The Second Affiliated Hospital of Guizhou University of Traditional Chinese MedicineGuiyang550001China

Dynamic changes in gut dysbiosis and metabolomic dysregulation are associated with immune-complex glomerulonephritis(ICGN).However,an in-depth study on this topic is currently ***,we report an ICGN model to address this *** was induced via the intravenous injection of cationized bovine serum albumin(c-BSA)into Sprague-Dawley(SD)rats for two weeks,after which mycophenolate mofetil(MMF)and losartan were administered *** and six weeks after ICGN establishment,fecal samples were collected and 16S ribosomal DNA(rDNA)sequencing and untargeted metabolomic were *** microbiota transplantation(FMT)was conducted to determine whether gut normali-zation caused by MMF and losartan contributed to their renal protective effects.A gradual decline in microbial diversity and richness was accompanied by a loss of renal *** 18 genera were found to have significantly different relative abundances between the early and later stages,and Marvinbryantia and Allobaculum were markedly upregulated in both *** metabolomics indicated that the tryptophan metabolism was enhanced in ICGN,characterized by the overproduction of indole and kynurenic acid,while the serotonin pathway was *** of losartan and MMF ameliorated microbial dysbiosis and reduced the accumulation of indoxyl conjugates in *** using feces from animals administered MMF and losartan improved gut dysbiosis by decreasing the Firmicutes/Bacteroidetes(F/B)ratio but did not improve renal *** findings indicate that ICGN induces serous gut dysbiosis,wherein an altered tryptophan metabolism may contribute to its *** and losartan significantly reversed the gut microbial and metabolomic dysbiosis,which partially contributed to their renoprotective effects.

关键词： Immune-complex glomerulonephritis Gut microbiome Metabolomics Fecal microbiota transplant Tryptophan metabolism