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Detailed analysis of the relativistic configuration of Bardeen anisotropic spheres in modified f(G)gravity

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Communications in Theoretical Physics 2024年第6期76卷 45-56页

作者： Adnan Malik Ayesha Almas Tayyaba Naz Rubab Manzoor M z Bhatti School of Mathematical Sciences Zhejiang Normal UniversityJinhuaZhejiangChina Department of Mathematics University of Management and TechnologySialkot CampusLahorePakistan National University of Computer and Emerging Sciences Lahore CampusPakistan Department of Mathematics University of Management and TechnologyJohar Town CampusLahore 54782Pakistan Department of Mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The aim of this work is to investigate anisotropic compact objects within the framework of f(G)modified theory of *** our present work,we utilize Krori-Barua metrics,i.e.,λ(r)=Xr^(2)+Y andβ(r)=zr^(2).We use some matching conditions of spherically symmetric spacetime with Bardeen's model as an exterior ***,we establish some expressions of energy density and pressure components to analyze the stellar configuration of Bardeen compact stars by assuming viable f(G)*** examine the energy conditions for different stellar structures to verify the viability of our considered ***,we also investigate some other physical features,such as equilibrium condition,equation of state parameters,adiabatic index,stability analysis,mass function,surface redshift,and compactness factor,*** is worthwhile to mention here for the current study that our stellar structure in the background of Bardeen's model is more viable and stable.

关键词： Bardeen compact stars f(G)modified gravity Krori-Barua potential

First wetland mapping at 10-m spatial resolution in South America using multi-source and multi-feature remote sensing data

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Science China Earth Sciences 2024年第10期67卷 3252-3269页

作者： Weiwei SUN Gang YANG Yuling HUANG Dehua MAO ke HUANG Lin zHU Xiangchao MENG Tian FENG Chao CHEN Yong GE Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China State key Laboratory of resources and Environmental Information System Institute of Geographic Sciences&Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Natural resources and Planning Bureau Shanghai Pudong New DistrictShanghai 200100China key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211China School of Geography Science and Geomatics Engineering Suzhou University of Science and TechnologySuzhou 215009China

Wetland degradation has been accelerating in recent years globally. Accurate information on the geographic distribution and categories of wetlands is essential for their conservation and management. Despite being the world′s fourth largest continent, South America has limited research on wetland mapping, and there is currently no available map that provides comprehensive information on wetland distribution and categories in the region. To address this issue, we used Sentinel-1, Sentinel-2 and SRTM data, developed a sample collection method and a wetland mapping method with a collection of multi-source features such as optical features, polarization features and shape features for South American wetlands. We produced a 10-m resolution wetland map based on the Google Earth Engine(GEE) platform. Our Level-1 wetland cover map accurately captured six wetland sub-categories with an overall accuracy of 96.24% and a kappa coefficient of 0.8649, while our Level-2 water cover map included five sub-categories with an overall accuracy of 97.23% and a kappa coefficient of0.9368. The results show that the total area of existing wetlands in South America is approximately 1,737,000 km~2, which is6.8% of the total land area. Among the ten wetland categories, shallow sea had the largest area(960,527.4 km~2), while aquaculture ponds had the smallest area 1513.6 km~2. Swamp had the second largest area(306,240.1 km~2). Brazil, Argentina,Venezuela, Bolivia, and Colombia were found to have the largest wetland areas, with Brazil and Colombia having the most diverse wetland categories. This product can serve as baseline data for subsequent monitoring, management, and conservation of South American wetlands.

关键词： Wetland mapping Google Earth Engine Sentinel imagery South America

Flat Band and η-Pairing States in a One-Dimensional MoiréHubbard Model

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Chinese Physics Letters 2024年第4期41卷 69-76页

作者：王冉宋智 College of Physics and Materials Science Tianjin Normal UniversityTianjin 300387China School of Physics Nankai UniversityTianjin 300071China

A Moirésystem is formed when two periodic structures have a slightly mismatched period,resulting in unusual strongly correlated states in the presence of particle-particle *** periodic structures can arise from the intrinsic crystalline order and periodic external *** investigate a one-dimensional Hubbard model with periodic on-site potential of period n_(0),which is commensurate to the lattice *** large n_(0),the exact solution demonstrates that there is a midgap flat band with zero energy in the absence of Hubbard *** Moiréunit cell contributes two zero energy levels to the flat *** the presence of Hubbard interaction,the midgap physics is demonstrated to be well described by a uniform Hubbard chain in which the effective hopping and on-site interaction strength can be controlled by the amplitude and period of the external *** simulations are performed to demonstrate the correlated behaviors in the finite-sized Moiré Hubbard system,including the existence of an η-pairing state and bound pair *** finding provides a method to enhance the correlated effect by a spatially periodic external field.

关键词： oscillation interaction field

Electrospun PCL/gelatin/arbutin nanofiber membranes as potent reactive oxygen species scavengers to accelerate cutaneous wound healing

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regenerative Biomaterials 2024年第3期3卷 43-55页

作者： Mindong Du Shuhan Liu Nihan Lan Ruiming Liang Shengde Liang Maoqiang Lan Disen Feng Li zheng Qingjun Wei ke Ma Department of Orthopaedics Trauma and Hand Surgery The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530521China Guangxi Engineering Center in Biomedical Materials for Tissue and Organ regeneration The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medicar UniversityNanning530021China Guangxi Collaborative Innovation Center for Biomedicine The First Affliated Hospital of Guangxi Medical UniversityGuangxi Medical UniversityNanning 530021China Department of Plastic&Cosmetic Surgery.The First Affliated Hospital of Guangxi Medical University Guangxi Medical UniversityNanning 530021China Pharmaceutical College Guangxi Medical UniversityNanning530021China

The presence of excessive reactive oxygen species(Ros)at a skin wound site is an important factor affecting wound *** scavenging,which regulates the ROS microenvironment,is essential for wound *** this study,we used novel electrospun PCL/gelatin/arbutin(PCL/G/A)nanofibrous membranes as wound dressings,with PCL/gelatin(PCL/G)as the backbone,and plantderived arbutin(hydroquinone-β-D-glucopyranoside,ARB)as an effective antioxidant that scavenges ROos and inhibits bacterial infection in *** loading of ARB increased the mechanical strength of the nanofibres,with a water vapour transmission rate of more than 2500g/(m^(2)×24h),and the water contact angle decreased,indicating that hydrophilicity and air permeability were significantly *** release and degradation experiments showed that the nanofibre membrane controlled the drug release and exhibited favourable *** experiments showed that the PCL/G/A nanofibre membranes were biocompatible,and DPPH and ABTS+radical scavenging experiments indicated that PCL/G/A could effectively scavenge ROS to reflect the antioxidant *** addition,haemostasis experiments showed that PCL/G/A had good haemostatic effects in vitro and in *** vivo animal wound closure and histological staining experiments demonstrated that PCL/G/A increased collagen deposition and remodelled epithelial tissue regeneration while showing good in vivo biocompatibility and *** conclusion,we successfully prepared a multifunctional wound dressing,PCL/G/A,for skin wound healing and investigated its potential role in wound healing,which is beneficial for the clinical translational application of phytomedicines.

关键词： arbutin nanofiber membranes wound dressing reactive oxygen species

Asymmetrical Fault Current Calculation Method and Influencing Factors Analysis of Droop-Controlled Inverters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 562-573页

作者： Huimin zhao zhikang Shuai Jun Ge An Luo Weimin Wu z.John Shen College of Electrical and Information Engineering Hunan UniversityChangsha 410006China Electrical Engineering Department Shanghai Maritime UniversityShanghai 201306China Department of Electrical and Computer Engineering Ilinois Institute of TechnologyChicagoIL 60616 USA

Since the fault dynamic of droop-controlled inverter is different from synchronous generators (SGs), protection devices may become invalid, and the fault overcurrent may damage power electronic devices and threaten the safety of the microgrid. Therefore, it is imperative to conduct a comprehensive fault analysis of the inverter to guide the design of protection schemes. However, due to the complexity of droop control strategy, existing literatures have simplified asymmetric fault analysis of droop-controlled inverters to varying degrees. Therefore, accurate fault analysis of a droop-controlled inverter is needed. In this paper, by analyzing the control system, an accurate fault model is established. Based on this, a calculation method for instantaneous asymmetrical fault current is proposed. In addition, the current components and current characteristics are analyzed. It was determined that fault currents are affected by control loops, fault types, fault distance and nonlinear limiters. In particular, the influences of limiters on the fault model, fault current calculation and fault current characteristics were analyzed. Through detailed analysis, it was found that dynamics of the control loop cannot be ignored, the fault type and fault distance determine fault current level, and part of the limiters will totally change the fault current trend. Finally, calculation and experimental results verify the correctness of the proposed method.

关键词： Asymmetrical fault analysis droop control fault current calculation method limiter transient fault characteristics

Atomic Manganese Manipulating Polysulfide Speciation Pathway for Room-Temperature Na-S Batteries

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CCS Chemistry 2024年第9期6卷 2289-2304页

作者： Hong zhang Mingli Wang Xiang-Long Huang Songtao Lu ke Lu Xiaohong Wu School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001 Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601 Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054

Sluggish polysulfide redox kinetics,especially the high energy barrier of rate-determining short-chain polysulfide conversion and the high activation barrier of Na_(2)S decomposition during sulfur recovery,compromise the full potential of rechargeable Na-S *** we construct the hierarchical sandwich-structured carbon matrix with atomically dispersed Mn-N4 Lewis acidic sites,taking advantage of their bidirectional electrocatalytic behavior toward interface-mediated reversible sulfur *** and theoretical results reveal that the spatial confinement and catalytic effects facilitated via strong Lewis acid-base electron interactions synergistically manipulate the low kinetically direct Na_(2)S_(4) to Na_(2)S conversion,and the formation of Mn-S bond minimizes the energy barrier of Na_(2)S electrochemical activation during battery recharging,thereby rendering a reversible and tunable polysulfide speciation ***,the degradation of the Na-S cell is due to the depletion of metal anode rather than the loss of active sulfur species and/or aggregation of inactive dead *** expected,the S@Mn/NC cathode delivers outstanding rate capability and ultrahigh cycling ***,a proof-of-concept pouch cell was also demonstrated capable of delivering an energy density up to 840 Wh kgcathode−*** tunable sulfur redox electrochemistry invoked by the bidirectional monodispersed Mn catalytic hot spots facilitates the efficient polysulfide speciation for practical Na-S cells.

关键词： single-atom manganese catalysts polysulfide manipulation reaction kinetics bidirectional catalysts sodium-sulfur batteries

Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts

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Journal of Environmental & Earth Sciences 2024年第1期6卷 11-18页

作者： H.Bâkiİz Independent Scholar Boca Raton Florida33496USA

Monitoring temporal changes in sea level is important in assessing coastal *** level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random *** them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level *** study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control *** approach is demonstrated using key West,Florida tide gauge *** mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the *** oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future.

关键词： Climate change Sea level variance X-bar S control charts

Advance on Chinese Medicine for Hypertensive renal Damage:Focus on the Complex Molecular Mechanisms

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Chinese Journal of Integrative Medicine 2024年第10期30卷 938-948页

作者： LU Yan XIE Xue-na XIN Qi-qi YUAN Rong MIAO Yu CONG Wei-hong CHEN ke-ji Laboratory of Cardiovascular Diseases Xiyuan Hospital of China Academy of Chinese Medical Sciences School of Pharmacy Macau University of Science and Technology National Clinical research Center for Chinese Medicine Cardiology

Hypertensive renal damage(HRD) is a major cause of end-stage renal disease. Among the causes of end-stage renal disease, HRD accounts for nearly 34% of the total number of cases. Antihypertensive treatment is primarily drug-based, but therapeutic efficacy is less effective and can have serious side effects. Chinese medicine(CM) has significant advantages in the treatment of HRD. CM is rich in various active ingredients and has the property of targeting multiple targets and channels. Therefore, the regulatory network of CM on disease is complex. A large number of CM have been employed to treat HRD, either as single applications or as part of compound formulations. The key possible mechanisms of CM for HRD include regulation of the renin-angiotensin-aldosterone system, antioxidation, anti-inflammation, rescue of endothelial function, regulation of vasoactive substance secretion and obesity-related factors, etc. This review summarized and discussed the recent advance in the basic research mechanisms of CM interventions for HRD and pointed out the challenges and future prospects.

关键词： Chinese medicine hypertensive renal damage molecular mechanisms research progress

Exploring formation mechanism and source attribution of ozone during the 2019 Wuhan Military World Games:Implications for ozone control strategies

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Journal of Environmental Sciences 2024年第2期136卷 400-411页

作者： Lei zhang Lili Wang Runyu Wang Nan Chen Yuan Yang ke Li Jie Sun Dan Yao Yuesi Wang Minghui Tao Yang Sun Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China Hubei Ecological Environment Monitoring Center Station Wuhan 430072China Guizhou research and Designing Institute of Environmental Sciences Guizhou Academy of Environmental Science and DesignGuiyang 550081China Jiangsu key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science and TechnologyNanjing 210044China School of Environment Key Laboratory for Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China key Laboratory of regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

A series of emission reduction measures were conducted in Wuhan,Central China,to ensure good air quality during the 7th Military World Games(MWG)in October *** better understand the implications for ozone(O_(3))pollution control strategies,we applied integrated analysis approaches based on the de-weathered statistical model,parameterization methods,chemical box model,and positive matrix factorization *** the MWG,concentrations of O_(3),NO_x,and volatile organic compound(VOCs),OFP(O_(3)formation potential),L_(OH)(OH radical loss rate)were 83μg/m^(3),43μg/m^(3),26 ppbv,188μg/m^(3),and 3.9 s^(-1),respectively,which were 26%,18%,3%,15%,and 13%lower than pre-MWG values and 6%,39%,30%,33%,and 50%lower than post-MWG values,*** removing meteorological influence,O_(3)and its precursors during the MWG decreased largely compared with post-MWG values,and only O_(3),NO_(2),and oxygenated VOCs(OVOCs)declined compared with pre-MWG values,which revealed the emission reduction measures during the MWG played an important role for O_(3)*** six VOCs sources,the mass contributions of biomass burning and solvents usage during the MWG decreased largely compared with pre-MWG values.O_(3)production was sensitive to VOCs and the key species were aromatics,OVOCs,and alkenes,which originated mainly from solvents usage,biomass burning,industrial-related combustion,and vehicle *** O_(3)concentration during the strict control was mainly caused by OVOCs reduction due to biomass burning ***,the O_(3)abatement strategies of Wuhan should be focused on the mitigation of high-reactivity VOCs.

关键词： VOCs Ozone Wuhan Military World Games Source apportionment relative incremental reactivity Random forest