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Remarks on the Global Existence for Incompressible Navier-Stokes Equations

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Chinese Annals of Mathematics,Series B 2024年第4期45卷 529-536页

作者： Sheng WANG Zexian ZHANG Yi zhou Shanghai Center for Mathematical Sciences Fudan UniversityShanghai 200433China School of Mathematics Science Fudan UniversityShanghai 200433China

In this article,the authors use the special structure of helicity for the threedimensional incompressible Navier-Stokes equations to construct a family of finite energy smooth solutions to the Navier-Stokes equations ... 详细信息

关键词： Navier-Stokes euqations Helicity Global existence Critical norm

Online interactive identification method based on ESO disturbance estimation for motion model of double propeller propulsion unmanned surface vehicle

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Control Theory and Technology 2024年第2期22卷 292-314页

作者： Yong Xiong Xianfei Wang Siwen zhou School of Navigation Wuhan University of TechnologyWuhan430063HubeiChina National Engineering Research Center for Water Transport Safety Wuhan430063HubeiChina Hubei Inland Technology Key Laboratory Wuhan430063HubeiChina

In this paper, the online parameter identification problem of the mathematical model of an unmanned surface vehicle (USV) considering the characteristics of the actuator is studied. A data-driven mathematical model of motion is very meaningful to realize trajectory prediction and adaptive motion control of the USV. An interactive identification algorithm (ESO–MILS, extended state observer–multi-innovation least squares) based on ESO is proposed. The robustness of online identification is improved by expanding the state observer to estimate the current disturbance without making artificial assumptions. Specifically, the three-degree-of-freedom dynamic equation of the double propeller propulsion USV is constructed. A linear model for online identification is derived by parameterization. Based on the least square criterion function, it is proved that the interactive identification method with disturbance estimation can improve the identification accuracy from the perspective of mathematical expectation. The extended state observer is designed to estimate the unknown disturbance in the model. The online interactive update improves the disturbance immunity of the identification algorithm. Finally, the effectiveness of the interactive identification algorithm is verified by simulation experiment and real ship experiment.

关键词： Identification of parameters Ship motion model Extended state observer Multinomial innovation least squares Interactive identification

An adaptive energy regulation in a memristive map linearized from a circuit with two memristive channels

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Communications in Theoretical Physics 2024年第3期76卷 42-50页

作者： Feifei Yang Ping zhou Jun Ma School of Science Chongqing University of Posts and TelecommunicationsChongqing 430065China College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Physics Lanzhou University of TechnologyLanzhou 730050China

Nonlinear circuits can show multistability when a magnetic flux-dependent memristor(MFDM) or a charge-sensitive memristor(CSM) is incorporated into a one branch circuit,which helps estimate magnetic or electric field *** this paper,two different kinds of memristors are incorporated into two branch circuits composed of a capacitor and a nonlinear resistor,thus a memristive circuit with double memristive channels is *** circuit equations are presented,and the dynamics in this oscillator with two memristive terms are ***,the memristive oscillator is converted into a memristive map by applying linear transformation on the sampled time series for the memristive *** Hamilton energy function for the memristive oscillator is obtained by using the Helmholtz theorem,and it can be mapped from the field energy of the memristive *** energy function for the dual memristive map is suggested by imposing suitable weights on the discrete energy *** dynamical behaviors of the new memristive map are investigated,and an adaptive law is proposed to regulate the firing mode in the memristive *** work will provide a theoretical basis and experimental guidance for oscillator-to-map transformation and discrete map energy calculation.

关键词： Hamilton energy dual memristive map adaptive energy regulation

Harnessing bacteria for tumor therapy:Current advances and challenges

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Chinese Chemical Letters 2024年第2期35卷 97-106页

作者： Lina Guo Jinsong Ding Wenhu zhou Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China Changsha Medical University Academician WorkstationChangsha 410219China Key Laboratory of Biological Nanotechnology of National Health Commission Changsha 410008China

After a century of standstill,bacteria-based tumor therapy has resurged recently benefiting from the revolution of tumor immunotherapy,which provides unique solutions to tackle the obstacles of traditional tumor *** and facultative anaerobes with active tropism can selectively colonize at tumor sites and suppress tumor growth via different mechanisms,serving as attractive tools for tumor treatment either as a monotherapy or combining with other therapies for synergistic anti-tumor *** this critical review,we introduce the recent advances of bacteria-based tumor therapy from the following ***,the general properties of bacteria are reviewed emphasizing on their structural components related to tumor immunotherapy,and the main bacteria that have been used in tumor therapy are ***,the benefits of bacteria for tumor therapy are illustrated,such as tumor targetability,deep penetration,and facile genetic engineering for attenuation,enhanced efficacy,as well as ***,anti-tumor mechanisms of bacteria are summarized,which refer to intrinsic tumoricidal activities,immune activation,bacteria metabolism,and their capability to regulate gut microbiota ***,bacteria could act as carriers to deliver various types of therapeutics to achieve combination therapy with improved *** addition,several challenges for anti-tumor applications of bacteria are discussed regarding the delivery,efficacy and safety issues,and potential solutions are also ***,the possible improvements and perspectives are discussed in the end,which provide a guideline for the design of advanced bacteria-based tumor therapeutics in the future.

关键词： Bacteria Tumor targeting Immunotherapy Combination therapy Genetic engineering Surface decoration

Efficient photocatalytic NADH regeneration with Rh-loaded Z-scheme mediator-free system

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Chinese Chemical Letters 2024年第2期35卷 496-500页

作者： Yi zhou Yiling He Ming Gao Ningkai Ding Juying Lei Yanbo zhou State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process East China University of Science and TechnologyShanghai 200237China National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery East China University of Science and TechnologyShanghai 200237China Shanghai Engineering Research Center for Multi-media Environmental Catalysis and Resource Utilization East China University of Science and TechnologyShanghai 200237China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Nicotinamide adenine dinucleotide(NADH)regeneration is necessary for the sustainable application of enzymatic *** Rh-based complex[Cp^(*)Rh(bpy)(H)]+has been widely used as an important mediator in NADH regeneration systems,but it is limited by complexity and high ***,a Z-scheme was constructed by loading Rh onto carbon nitride nanosheets/carbon nitride quantum dots(CN-CNQD).The resultant catalyst achieved a high yield of NADH in a mediator-free(M-free)system of 0.283 mmol L^(−1) g^(−1) min^(−1),which is 5.29 times that of pure *** enzyme introduction experiments confirmed that the enzyme active product 1,4-NADH could reach 34.21%selectivity in the M-free *** research revealed that the heterojunction between CNs and CNQDs improved the NADH regeneration activity in the traditional M-involved system,while Rh loading was proved to optimize the yield and selectivity of 1,4-NADH in M-free *** immobilized Rh shows more competitiveness than[Cp^(*)Rh(bpy)(H)]^(+).This study contributes to the construction of an M-free system for further application in greener,lower-cost enzymatic processes.

关键词： Photocatalysis NADH regeneration Mediator-free Carbon nitride Z-scheme

Geological modeling of coalbed methane reservoirs in the tectonically deformed coal seam group in the Dahebian block,western Guizhou,China

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Frontiers of Earth Science 2024年第1期18卷 44-67页

作者： Yong SHU Shuxun SANG Xiaozhi zhou Key Laboratory of Coalbed Methane Resources and Reservoir Formation Process(Ministry of Education) China University of Mining and TechnologyXuzhou 221116China Carbon Neutrality Institute China University of Mining and TechnologyXuzhou 221008China School of Resources and Geosciences China University of Mining and TechnologyXuzhou 221116China Jiangsu Key Laboratory of Coal-based Greenhouse Gas Control and Utilization China University of Mining and TechnologyXuzhou 221008China

The widely spread Carboniferous-Permian coal seam group in southern China has great potential for coalbed methane resources,but the extensively developed tectonically deformed coal seriously restricts its *** the Dahebian block in western Guizhou as the study area,the geological model of coalbed methane reservoirs in the tectonically deformed coal seam group was established,and the spatial distribution pattern of model parameters was clarified by clustering algorithms and factor *** facies model suggests that the main coal body structures in Nos.1,4,and 7 coal seams are cataclastic coal and granulated coal,whereas the No.11 coal seam is dominated by granulated coal,which has larger thicknesses and spreads more *** in situ permeability of primary undeformed coal,cataclastic coal,granulated coal,and mylonitized coal reservoirs are 0.333 mD,0.931 mD,0.146 mD,and 0.099 mD,respectively,according to the production performance analysis *** property model constructed by facies-controlled modeling reveals that Nos.1,4,and 7 coal seams have a wider high-permeability area,but the gas content is lower;the high-permeability area in the No.11 coal seam is more limited,but the gas content is *** results of the self-organizing map neural network and K-means clustering indicate that the geological model can be divided into 6 clusters,the model parameter characteristics of the 6 clusters are summarized by data analysis in combination with 6 factors extracted by factor analysis,and the application of data analysis results in multi-layer coalbed methane co-development is *** study provides ideas for the geological modeling in the tectonically deformed coal seam group and its data analysis.

关键词： geological modeling tectonically deformed coal coal seam group clustering algorithm Dahebian block,western Guizhou

Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo Gang zhou Xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

Nanoscopic tribological characteristics of a cryogenically cycled Zr-based metallic glass

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 113-126页

作者： Qian Jia Qiaosheng Xia Qing zhou Yucheng Wang Yue Ren Yu Meng Haifeng Wang Feng zhou State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Surface Engineering and Remanufacturing Xi’an UniversityXi’an 710065China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Optimized macroscopic tribological behavior can be anticipated in metallic glasses(MGs)by cryogenic cycling treatment(CCT),which is attributed to enhanced ***,the intrinsic friction mechanisms of MGs induced by cryogenic rejuvenation are still poorly *** the present study,nanoscopic wear tests were conducted on the Zr-based MGs surface with different CCT cycles using atomic force microscopy(AFM).After CCT treatment with 100 cycles,the MG displays the highest adhesion and ploughing frictions,but significantly improved anti-wear *** tests and molecular dynamics simulations disclose that the increased adhesion is attributed to the dominance of liquid-like regions in the CCT-treated MGs,and the impact of reduced hardness and weak elastic recovery results in the deteriorated ploughing *** enhanced plasticity effectively dissipates the strain from the AFM tip through multiple shear bands and weakens the adhesion during deformation,giving rise to excellent wear *** study elucidates the promoting effect of CCT on the outstanding antiwear performance of MGs,and is helpful for the development of novel alloys.

关键词： metallic glasses cryogenic cycling treatment nanoscope wear friction mechanism

Deep learning-based intelligent precise aeration strategy for factory recirculating aquaculture systems

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Artificial Intelligence in Agriculture 2024年第2期12卷 57-71页

作者： Junchao Yang Yuting zhou Zhiwei Guo Yueming zhou Yu Shen School of Artificial Intelligence Chongqing Technology and Business UniversityChongqing 400067China National Research Base of Intelligent Manufacturing Services Chongqing Technology and Business UniversityChongqing 400067China

Factory recirculating aquaculture system(RAS)is facing in a stage of continuous research and technological *** aquaculture is an important direction for the future development of ***,the RAS nowdays still has poor self-learning and optimal decision-making capabilities,which leads to high aqua-culture cost and low running *** this paper,a precise aeration strategy based on deep learning is de-signed for improving the healthy growth of breeding ***,the situation perception driven by computer vision is used to detect the hypoxia *** combined with the biological energy model,it is constructed to calculate the breeding objects oxygen ***,the optimal adaptive aeration strategy is generated according to hypoxia behavior judgement and biological energy *** results show that the energy consumption of proposed precise aeration strategy decreased by 26.3%compared with the man-ual control and 12.8%compared with the threshold ***,stable water quality conditions acceler-ated breeding objects growth,and the breeding cycle with the average weight of 400 g was shortened from 5 to 6 months to 3–4 months.

关键词： Recirculating aquaculture system Precise aeration Deep learning Intelligent control