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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying Huang jia-ming Wang Zhen-he feng xu Sun MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical Engineering Northwestern Polytechnical University Shanghai Institute of Space Power-Sources Ningbo Institute of Northwestern Polytechnical University

Silicon-based（Si-based） materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO2carbon fibers（TiO2CFs） via electrospinning, after which they were encapsulated with MXene and Co-MoS2（CMS） nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO2CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO2CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Co-MoS2 nanosheets Hierarchical structure Lithium-ion batteries MXene Si particles

Innovative mesenchymal stem cell treatments for fatty liver disease

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World Journal of Stem Cells 2024年第9期16卷 846-853页

作者： Fei-Qiong Gao jia-Qi Zhu xu-Dong feng Department of Endocrinology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhou 310003Zhejiang ProvinceChina Laboratory Medicine Center Department of Clinical LaboratoryZhejiang Provincial People’s HospitalPeople’s Hospital of Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Department of Clinical Laboratory Ningbo Medical Center Lihuili HospitalAffiliated Lihuili Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina

The incidence of non-alcoholic fatty liver disease(NAFLD)and alcohol-associated liver disease(ALD)is increasing year by year due to changes in the contemporary environment and dietary structure,and is an important public health problem *** is an urgent need to continuously improve the understanding of their disease mechanisms and develop novel therapeutic *** stem cells(MSCs)have shown promise as a potential therapeutic strategy in therapeutic studies of NAFLD and *** and ALD have different triggers and their specific mechanisms of disease progression are different,but both involve disease processes such as hepatocellular steatosis and potential fibrosis,cirrhosis,and even hepatocellular *** have metabolic regulatory,anti-apoptotic,antioxidant,and immunomodulatory effects that together promote liver injury repair and functional recovery,and have demonstrated positive results in preclinical *** editorial is a continuum of jiang et al’s review focusing on the advantages and limitations of MSCs and their derivatives as therapeutics for NAFLD and *** detail how MSCs attenuate the progression of NAFLD by modulating molecular pathways involved in glucolipid metabolism,inflammation,oxidative stress,endoplasmic reticulum stress,and *** on recent advances,we discuss MSCs and their derivatives as therapeutic strategies for NAFLD and ALD,providing useful information for their clinical application.

关键词： Alcohol-associated liver disease Non-alcoholic fatty liver disease Mesenchymal stem cells Cell therapy Inflammation

Variability of urban fractional vegetation cover and its driving factors in 328 cities in China

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Science China Earth Sciences 2024年第2期67卷 466-482页

作者： Fei feng Xin YANG Baoquan jia Xiaoting LI Xianwen LI Chengyang xu Kaicun WANG Research Centre of Urban Forestry Key Laboratory for Silviculture and Forest Ecosystem of State Forestry and Grassland AdministrationBeijing Forestry UniversityBeijing100083China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Research Institute of Forestry Chinese Academy of ForestryBeijing100091China School of Architecture Tsinghua UniversityBeijing100084China College of Urban and Environmental Sciences Sino-French Institute for Earth System ScienceInstitute of Carbon NeutralityPeking UniversityBeijing100871China

Urban green space promotes the health of urban residents,enhances urban ecosystem biodiversity,mitigates environmental pollution,and attenuates urban heat island ***,urban vegetation cover is highly heterogeneous and difficult to *** this study,the variation of urban fractional vegetation cover(FVC)in 328 cities in China from 1990 to2022 was quantified based on Landsat satellite data at a 30-m *** was found that from 1990 to 2005,due to increases in building density and impervious surfaces in cities,the national mean urban vegetation cover decreased from 0.38 to ***2005,urban vegetation cover began to reverse,reaching 0.45 in *** increasing trend was most pronounced in newly built urban *** decrease in average urban vegetation cover before 2005 was mainly due to the expansion of low vegetation cover areas,while the increase in urban vegetation cover after 2005 manifested as the expansion of high vegetation cover *** reversal in the trend of urban vegetation cover change after 2004 is related to the gradual implementation of national policies requiring increased urban green space *** urban gross domestic product(GDP)showed the highest correlation with changes in urban vegetation *** large and medium-sized cities,the top three factors influencing vegetation cover were GDP,urban population,and ***,for cities in arid/semi-arid regions,changes in vegetation cover were more sensitive to climatic factors(such as precipitation).Although the urban vegetation cover in China has substantially increased in recent years,the urban green space in small-sized cities and in the old urban districts of large-sized cities still have room to improve.

关键词： Urban vegetation Urban vegetation cover Urbanization Remote sensing

Multifunctional Film Assembled from N‑Doped Carbon Nanofiber with Co–N_(4)–O Single Atoms for Highly Efficient Electromagnetic Energy Attenuation

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Nano-Micro Letters 2024年第11期16卷 359-376页

作者： jia xu Bei Li Zheng Ma Xiao Zhang Chunling Zhu feng Yan Piaoping Yang Yujin Chen College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001People’s Republic of China Key Laboratory of In‑Fiber Integrated Optics College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China

Single-atom materials have demonstrated attractive physicochemical ***,understanding the relationships between the coordination environment of single atoms and their properties at the atomic level remains a considerable ***,a facile waterassisted carbonization approach is developed to fabricate well-defined asymmetrically coordinated Co–N_(4)–O sites on biomass-derived carbon nanofiber(Co–N_(4)–O/NCF)for electromagnetic wave(EMW)*** such nanofiber,one atomically dispersed Co site is coordinated with four N atoms in the graphene basal plane and one oxygen atom in the axial ***-depth experimental and theoretical studies reveal that the axial Co–O coordination breaks the charge distribution symmetry in the planar porphyrin-like Co–N_(4) structure,leading to significantly enhanced dielectric polarization loss relevant to the planar Co–N_(4) ***,the film based on Co–N_(4)–O/NCF exhibits light weight,flexibility,excellent mechanical properties,great thermal insulating feature,and excellent EMW absorption with a reflection loss of−45.82 dB along with an effective absorption bandwidth of 4.8 *** findings of this work offer insight into the relationships between the single-atom coordination environment and the dielectric performance,and the proposed strategy can be extended toward the engineering of asymmetrically coordinated single atoms for various applications.

关键词： Co single atoms Asymmetric coordination structure Axial oxygen coordination Electromagnetic wave absorption Multifunctional film

An origami shield with supporting frame structures optimized by a feature-driven topology optimization method

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Defence Technology（防务技术） 2024年第1期31卷 447-456页

作者： Dongsheng jia Pengcheng feng Liangdi Wang Longcan Chen Jun Wang Jihong Zhu Yingjie xu Weihong Zhang State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an710072China

In this paper,the design,manufacture and testing of an origami protective shield with a supporting frame structure are *** consists of an origami shield surface and a deployable supporting frame structure that needs to be portable and sufficiently ***,for the design of the shield surface,a threestage origami crease pattern is developed to reduce the shield size in the folded *** shield surface consists of several stiff modular panels and layered with flexible *** modular panels are made of a multi-layer composite where a ceramic layer is made of small pieces to improve durability as those small pieces enable restriction of crack ***,the supporting frame structure is designed as a chain-of-bars structure in order to fold into a highly compact state as a bundle of bars and deploy in ***,a feature-driven topology structural optimization method preserving component sequence is developed where the inter-dependence of sub-structures is taken into account.A bar with semi-circular ends is used as a basic design *** positions of the bar’s end points are treated as design variables and the width of the bars is kept ***,a constraint on the total length of the chain of bars is ***,the modular panels made of multi-layer composite and the full-scale prototype of the origami shield are fabricated and tested to verify the bullet-proof performance.

关键词： Origami Deployable structure Structure design Shield Composite materials

An index system for evaluation of agriculture green development at county level in China

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 55-68页

作者： Xiao xu Yanxiang jia Yuan feng Haixing ZHANG Wen xu Qichao ZHU Beautiful Rural Construction Center Quzhou 324003China College of Resources and Environment China Agricultural UniversityBeijing 100193China National Academy of Agriculture Green Development China Agricultural UniversityBeijing 100193China

Agriculture green development(AGD)has become an unavoidable choice to address the unique national circumstances of *** study established a county-level AGD evaluation index system,comprised three dimensions,food production,ecological environment and socioeconomic development,using 20 *** assessment delved into historical trend and current situation,utilizing Spearman rank correlation analysis to analyze trade-off and synergy relationships,using Quzhou County,Hebei Province as a case *** main findings were in four ***,the index for AGD in Quzhou County increased by 58.9%from 1978 to *** major contribution were the social economy(65.8%)and food production(53.5%),whereas the ecological environment was found to have had a negative ***,in 2019,the AGD index was only 56.4,indicating substantial potential for improvement relative to the target value.A notable difference in scores existed between the three dimensions,with the order being ecological environment(66.3)>food production(61.7)>socioeconomic(41.3).Also,90%of the indicators did not reach the target ***,relationship analysis of the indicators revealed that the synergistic effect exceeded the trade-off ***,46.3%of the indicators had no significant relationship,35.3%had a synergistic relationship,and 18.4%had a trade-off ***,interdimensional indicator relationships exhibited a trade-off effect between the ecological environment and both food production and socioeconomic ***,a positive trend of synergy between production and ecology has emerged since *** conclusion,the quantitative evaluation index system exposed the unbalanced development and significant potential relative to the target value of AGD in Quzhou County,despite notable progress.

关键词： Agriculture green development index system quantitative evaluation Spearman correlation analysis

Bayesian inference of neutron-skin thickness and neutron-star observables based on effective nuclear interactions

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 97-105页

作者： jia Zhou Jun xu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China School of Physics Science and Engineering Tongji UniversityShanghai 200092China

We have obtained the constraints on the density dependence of the symmetry energy from neutron-skin thickness data by parityviolating electron scatterings and neutron-star observables using a Bayesian approach,based on the standard Skyrme-HartreeFock(SHF)model and its extension as well as the relativistic mean-field(RMF)*** the neutron-skin thickness data(neutron-star observables)mostly constrain the symmetry energy at subsaturation(suprasaturation)densities,they may more or less constrain the behavior of the symmetry energy at suprasaturation(subsaturation)densities,depending on the energy-density functional *** showing the final posterior density dependence of the symmetry energy,we also compare the slope parameters of the symmetry energy at 0.10 fm-3as well as the values of the symmetry energy at twice saturation density from three effective nuclear *** present work serves as a comparison study based on relativistic and non-relativistic energy-density functionals,for constraining the nuclear symmetry energy from low to high densities using a Bayesian approach.

关键词： symmetry energy neutron skin neutron star

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All‑Covalent Organic Framework Nanofilms Assembled Lithium‑Ion Capacitor to Solve the Imbalanced Charge Storage Kinetics

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Nano-Micro Letters 2024年第6期16卷 246-260页

作者： Xiaoyang xu jia Zhang Zihao Zhang Guandan Lu Wei Cao Ning Wang Yunmeng Xia Qingliang feng Shanlin Qiao College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018People’s Republic of China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China Hebei Engineering Research Center of Organic Solid Photoelectric Materials for Electronic Information Shijiazhuang 050018People’s Republic of China

Free-standing covalent organic framework(COFs)nanofilms exhibit a remarkable ability to rapidly intercalate/de-intercalate Li^(+) in lithium-ion batteries,while simultaneously exposing affluent active sites in *** development of these nanofilms offers a promising solution to address the persistent challenge of imbalanced charge storage kinetics between battery-type anode and capacitor-type cathode in lithium-ion capacitors(LICs).Herein,for the first time,custom-made COFBTMB-TP and COFTAPB-BPY nanofilms are synthesized as the anode and cathode,respectively,for an all-COF nanofilm-structured *** COFBTMB-TP nanofilm with strong electronegative–CF3 groups enables tuning the partial electron cloud density for Li^(+) migration to ensure the rapid anode kinetic *** thickness-regulated cathodic COFTAPB-BPY nanofilm can fit the anodic COF nanofilm in the *** to the aligned 1D channel,2D aromatic skeleton and accessible active sites of COF nanofilms,the whole COFTAPB-BPY//COFBTMB-TP LIC demonstrates a high energy density of 318 mWh cm^(−3) at a high-power density of 6 W cm^(−3),excellent rate capability,good cycle stability with the capacity retention rate of 77%after *** COFTAPB-BPY//COFBTMB-TP LIC represents a new benchmark for currently reported film-type LICs and even film-type *** being comprehensively explored via ex situ XPS,7Li solid-state NMR analyses,and DFT calculation,it is found that the COFBTMB-TP nanofilm facilitates the reversible conversion of semi-ionic to ionic C–F bonds during lithium ***-TP exhibits a strong interaction with Li^(+) due to the C–F,C=O,and C–N bonds,facilitating Li^(+) desolation and absorption from the *** work addresses the challenge of imbalanced charge storage kinetics and capacity between the anode and cathode and also pave the way for future miniaturized and wearable LIC devices.

关键词： Covalent organic frameworks Lithium-ion capacitor Charge storage kinetic

Even-odd layer-dependent multiferroic in freestanding rare-earth orthorhombic perovskite

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 151-157页

作者： Shaowen xu Fanhao jia Ning Dai School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Physics College of ScienceHangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

Freestanding oxide perovskites possess strong interlayer coupling between adjacent atomic layers,thus exerting a determinative effect on the magnetism and ferroelectricity of these atomic-scale ***,we propose an effective strategy to manipulate magnetism and ferroelectricity in freestanding rare-earth orthorhombic perovskite via modulation of layer *** performing first-principles calculations,an even-odd oscillation is demonstrated in few-layer GdAlO_(3)perovskite(GAP).Specifically,odd-layer systems with charged atomic layers are ferromagnetic polar metals,while even-layer systems are antiferromagnetic ferroelectric *** thickness-dependent magnetic phase transition originates from carrier doping,as rationalized by the Stoner ***,we demonstrate the promotion of in-plane ferroelectricity via the concurrent application of two distinct antiferrodistortive displacements,each driven by formation and breaking of *** multiferroic phases may emerge in other transition metal oxide perovskites supporting multiple valence states,e.g.,few-layer Gd MO_(3)(M=V,Cr,Mn,and Ni).This work puts forward a strategy for layer thickness engineering of magnetism and ferroelectricity in 2D oxide perovskite multiferroic materials.

关键词： few-layer rare-earth perovskite multiferroicity size effect first principles calculations

Contribution of high-latitude permafrost regions in the Northern Hemisphere to global wildfire carbon emissions

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Science China Earth Sciences 2024年第10期67卷 3239-3251页

作者： Xingru ZHU Xiyan xu Gensuo jia Key Laboratory of Regional Climate-Environment for East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Wildfires are major disturbances in permafrost ecosystems, with increasing frequency and intensity in recent years. In permafrost regions, wildfires not only burn surface and subsurface organic matter but also accelerate permafrost thawing,releasing significant amounts of greenhouse gases such as carbon dioxide and methane into the atmosphere. However, the contribution of high-latitude permafrost regions in the Northern Hemisphere to global wildfire carbon emissions remains poorly understood. This study integrates remote sensing data and ground observations to analyze the contributions of aboveground and belowground fuel combustion in high-latitude permafrost regions to global wildfire carbon emissions from 2002 to 2020, as well as the spatiotemporal variations in these contributions. Our findings indicate that permafrost regions contribute approximately11.96% of global wildfire carbon emissions, with aboveground emissions accounting for approximately 3.94% of global aboveground emissions and belowground emissions contributing approximately 63.57% of global belowground emissions. The contribution of high-latitude permafrost regions to global emissions peaked in July and August, whereas the continuous permafrost zones(areas with more than 90% permafrost coverage) showed the most significant increase in June and July. The contributions of both aboveground and belowground emissions from high-latitude permafrost regions to global wildfire emissions have been increasing, primarily due to the reduction in global wildfire emissions, in contrast with the rising emissions from wildfires in high-latitude permafrost regions. This study highlights the significant role of wildfires, particularly the combustion of belowground biomass in high-latitude permafrost regions, in global carbon emissions. The decomposition and combustion of organic carbon in permafrost regions due to wildfires release more greenhouse gases into the atmosphere, potentially amplifying the positive feedback

关键词： Wildfire Permafrost Carbon emissions Climate change Belowground fuel consumption

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