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On Leray's problem in an infinitely long pipe with the Navier-slip boundary condition

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science China Mathematics 2024年第4期67卷 819-854页

作者： Zijin Li Xinghong Pan jiaqi yang school of Mathematics and statistics Nanjing University of Information Science and TechnologyNanjing 210044China school of Mathematics and Key Laboratory of Ministry of Industry and Information Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China school of Mathematics and statistics Northwestern Polytechnical UniversityXi'an 710129China

The original Leray’s problem concerns the well-posedness of weak solutions to the steady incompressible Navier-stokes equations in a distorted pipe,which approach the Poiseuille flow subject to the no-slip boundary condition at spatial *** this paper,the same problem with the Navier-slip boundary condition instead of the no-slip boundary condition,is *** to the complexity of the boundary condition,some new ideas,presented as follows,are introduced to handle the extra difficulties caused by boundary ***,the Poiseuille flow in the semi-infinite straight pipe with the Navier-slip boundary condition will be introduced,which will serve as the asymptotic profile of the solution to the generalized Leray’s problem at spatial ***,a solenoidal vector function defined in the whole pipe,satisfying the Navierslip boundary condition,having the designated flux and equalling the Poiseuille flow at a large distance,will be carefully *** plays an important role in reformulating our ***,the energy estimates depend on a combined L2-estimate of the gradient and the stress tensor of the velocity.

关键词： stationary Navier-stokes system Navier-slip boundary condition Leray's problem

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Pathological BBB Crossing Melanin-Like Nanoparticles as Metal-Ion Chelators and Neuroinflammation Regulators against Alzheimer’s Disease

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Research 2024年第1期6卷 687-706页

作者： Qianqian Huang Chaoqing jiang Xue Xia Yufan Wang Chenxing Yan Xiaorong Wang Ting Lei Xiaotong yang Wenqin yang Guo Cheng Huile Gao Key Laboratory of Drug-Targeting and Drug Delivery system of the Education Ministry West China School of PharmacySichuan UniversityChengdu 610041P.R.China Laboratory of Molecular Translational Medicine Center for Translational MedicineKey Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University)Ministry of EducationDepartment of PediatricsWest China Second University HospitalSichuan UniversityChengdu 610041P.R.China

Inflammatory responses,manifested in excessive oxidative stress and microglia overactivation,together with metal ion-triggered amyloid-beta(Aβ)deposition,are critical hallmarks of Alzheimer’s disease(AD).The intricate pathogenesis causes severe impairment of neurons,which,in turn,exacerbates Aβaggregation and facilitates AD ***,multifunctional melanin-like metal ion chelators and neuroinflammation regulators(named PDA@K)were constructed for targeted treatment of *** this platform,intrinsically bioactive material polydopamine nanoparticles(PDA)with potent metal ion chelating and ROs scavenging effects were decorated with the KLVFF peptide,endowing the system with the capacity of enhanced pathological blood–brain barrier(BBB)crossing and lesion site accumulation via Aβ*** vitro and in vivo experiment revealed that PDA@K had high affinity toward Aβand were able to hitch a ride on Aβto achieve increased pathological BBB *** engineered PDA@K effectively mitigated Aβaggregate and alleviated neuroinflammation.

关键词： oxidative aggregation chelating

Unique polysulfide reaction on VO_(2) for restraining shuttle effect in soft-packaged Li-s pouch cells

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Rare Metals 2024年第6期43卷 2842-2850页

作者： Ruo-Xuan yang Qing-Chun Zhang jing-sheng Cai Xuan Cao Qin yang Ying-Ze song Wei Zhang state Key Laboratory of Environment-Friendly Energy Materials Tianfu Institute of Research and InnovationSchool of Materials and ChemistrySouthwest University of Science and TechnologyMianyang 621010China school of Materials Engineering Changshu Institute of TechnologyChangshu 215500China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China

The shuttle phenomenon and retarded conversion kinetics of lithium poly sulfides(LiPss)are relatively severe in lithium-sulfur(Li-s)pouch *** to their redox potential in the sulfur working window,VO_(2)nanobelts show ... 详细信息

关键词： mechanism sulfide lithium

Pollution characteristics and source apportionment of heavy metal(loid)s in soil and groundwater of a retired industrial park

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journal of Environmental sciences 2024年第9期143卷 23-34页

作者： Zijing Xiang shijin Wu Lizhong Zhu Kun yang Daohui Lin Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Department of Environmental SciencesZhejiang UniversityHangzhou 310058China Zhejiang Ecological Civilization Academy Anji 313300China

Heavy metal(loid)s(HMs)pollution has become a common and complex problem in industrial parks due to rapid industrialization and ***,soil and groundwater were sampled from a retired industrial park to investigate the pollution characteristics of *** show that Ni,Pb,Cr,Zn,Cd,and Cu were the typical HMs in the *** analysis with the positive matrix factorization model indicates that HMs in the topsoil stemmed from industrial activities,traffic emission,and natural source,and the groundwater HMs originated from industrial activities,groundwater-soil interaction,groundwater-rock interaction,and atmosphere *** sequential extraction of soil HMs reveals that As and Hg were mainly distributed in the residue fraction,while Ni,Pb,Cr,Zn,Cd,and Cu mainly existed in the mobile *** HMs either in the total concentration or in the bioavailable fraction preferred to retain in soil as indicated by their high soil-water partitioning coefficients(K_(d)),and the K_(d) values were correlated with soil pH,groundwater redox potential,and dissolved *** relative stable soil-groundwater circumstance and the low active fraction contents limited the vertical migration of soil HMs and their release to *** findings increase our knowledge about HMs pollution characteristics of traditional industrial parks and provide a protocol for HMs pollution scrutinizing in large zones.

关键词： Heavy metal(loid)s Industrial park source apportionment Chemical fraction soil-groundwater partitioning

Hierarchical V_(3)s_(4)/C nanofibers with fast kinetics for superior alkali metal batteries

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Rare Metals 2024年第4期43卷 1836-1844页

作者： Li Chen Zhi-Xin Rao Zhi Chen Zhao-Hui Wu shuai yang Zhi-jun Feng Hui-Yong yang Fan-Yan Zeng Xi-Bao Li jin-yang Hu jun-Tong Huang school of Materials science and Engineering Nanchang Hangkong UniversityNanchang330063China school of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang330063China

Owing to the numerous benefits,including low cost and great theoretical capacity,V3s4 has been a research hotspot for Li^(+)/Na^(+)/K^(+) ***,the V_(3)s_(4) electrode with long cycling stability and high specific capacities continues to pose significant *** this work,vacuum vulcanization is combined with electrospinning to synthesize V_(3)s_(4)/C composite nanofibers(V_(3)s_(4)@CNF).

关键词： composite fibers kinetics

A two-step multi-frequency receiver function inversion method for shallow crustal s-wave velocity structure and its application across the basin-mountain range belts in Northeast China

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science China Earth sciences 2024年第3期67卷 687-703页

作者： Ruihao yang Xu WANG Ling CHEN Mingye FENG Qifu CHEN state Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

A shallow crustal velocity structure(above 10 km depth) is essential for understanding the crustal structures and deformation and assessing the exploration prospect of natural resources, and also provides priori information for imaging deeper crustal and mantle structure. Passive-source seismic methods are cost-effective and advantageous for regional-scale imaging of shallow crustal structures compared to active-source methods. Among these passive methods, techniques utilizing receiver function waveforms and/or body-wave amplitude ratios have recently gained prominence due to their relatively high spatial resolution. However, in basin regions, reverberations caused by near-surface unconsolidated sedimentary layers often introduce strong non-uniqueness and uncertainty, limiting the applicability of such methods. To address these challenges, we propose a two-step inversion method that uses multi-frequency P-RF waveforms and P-RF horizontal-to-vertical amplitude ratios. synthetic tests indicate that our two-step inversion method can mitigate the non-uniqueness of the inversion and enhance the stability of the results. Applying this method to teleseismic data from a linear seismic array across the sedimentary basins in Northeast China, we obtain a high-resolution image of the shallow crustal s-wave velocity structure along the array. Our results reveal significant differences between the basins and mountains. The identification of low-velocity anomalies(s^(-1)) at depths less than 1.0 km beneath the Erlian Basin and less than 2.5 km beneath the songliao Basin suggests the existence of sedimentary layers. Moreover, the high-velocity anomalies(~3.4–3.8 km s^(-1)) occurring at depths greater than 7 km in the songliao Basin may reflect mafic intrusions emplaced during the Early Cretaceous. Velocity anomaly distribution in our imaging result is consistent with the location of the major faults, uplifts, and sedimentary depressions, as well as active-source seismic res

关键词： Receiver function Frequency dependence Two-step inversion shallow crustal velocity structures Unconsolidated sedimentary basins

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Ambarzumyan's Theorem for the Dirac Operator on Equilateral Tree Graphs

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Acta Mathematicae Applicatae sinica 2024年第2期40卷 568-576页

作者： Dong-jie WU Xin-jian XU Chuan-Fu yang Department of Mathematics School of Mathematics and StatisticsNanjing University of Science and TechnologyNanjing 210094China

The classical Ambarzumyan’s theorem states that if the Neumann eigenvalues of the sturm-Liouville operator-d^(2)/dx^(2)+q with an integrable real-valued potential q on[0,π] are {n^(2):n≥0},then q=0 for almost all x∈[0,π].In this work,the classical Ambarzumyan’s theorem is extended to the Dirac operator on equilateral tree *** prove that if the spectrum of the Dirac operator on graphs coincides with the unperturbed case,then the potential is identically zero.

关键词： dirac operator quantum graph Ambarzumyan’s theorem inverse spectral problem

Does City shape Affect China's Economic Development?

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China & World Economy 2024年第1期32卷 21-56页

作者： Wei Zou Fei yang Economics and Management school Wuhan UniversityChina

This paper constructs a general equilibrium spatial urban model and measures city geometric compactness using the patch-shape index based on evidence from satellite imagery and basic vector maps of *** adopts the ordinary least squares and instrumental variable approaches to examine the effect of city shape on the urban development of 279 Chinese cities at or above the prefecture *** empirical results show that there was a significant negative correlation between city shape and economic ***,every 1 percentage point increase in the patch-shape index led to a decrease in city-scale GDP by 0.009 percent,housing prices by 0.044 percent,and wages by 0.024 *** compact urban layouts attracted an inflow of households and firms,stimulated city economic growth,and were associated with increased housing prices and wage *** paper considers the cities'initial conditions,trends in population changes(expanding,shrinking,and stagnant cities),and geographic factors,and finds that the results are *** array of policy implications can be drawn from the research.

关键词： city footprint compactness economic development urban spatial shape

ZnGa_(2)s_(4):an infrared nonlinear optical material with large second-harmonic generation response and wide band gap

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Rare Metals 2024年第1期43卷 395-401页

作者： Chen-yang Zhang Xiao-Nan Niu Yan-Feng Wei shu-Xing Zhou Da-Qing yang Ying Wang jian Wang Bing-Bing Zhang College of Chemistry and Materials science Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationState Key Laboratory of New Pharmaceutical Preparations and ExcipientsHebei UniversityBaoding 071002China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Hubei Longzhong Laboratory Xiangyang 441000China Department of Chemistry and Biochemistry Wichita State UniversityKansas 67260USA

High-performance nonlinear optical(NLO)crystals are crucial devices to convert wavelength of solid-state *** play an indispensable role in the research of infrared NLO *** this work,ternary chalcogenide ZnGa_(2)s_(4) ... 详细信息

关键词： optical nonlinear harmonic