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Journal of Materials Science & Technology 2024年第3期170卷 200-211页

作者： Yanyan Zhao Xu fan Hongxing Zheng enzhou Liu Jun fan Xuejun Wang College of Biology Pharmacy and Food engineering Shangluo UniversityShangluo 726000China QinLing-Bashan Mountains Bioresources Comprehensive Development C.i.C. Shaanxi University of TechnologyHanzhong 723001China School of Chemical engineering Northwest UniversityXi’an 710069China

Constructing of heterojunction was identified as a feasible way to improve photocatalytic activity of *** this work,a n-p type Bi_(2)WO_(6)/AginS_(2)S-scheme heterojunction was successfully prepared for organic pollutants *** Bi_(2)WO_(6)/AginS_(2)S-scheme heterojunction exhibited much higher pho-tocatalytic activity towards Rhodamine B(92.24%,expose to visible light for 60 min),norfloxacin(81.73%,expose to visible light for 90 min)and levofloxacin(87.46%,expose to visible light for 90 min)than pure Bi_(2)WO_(6)and pure AginS_(2).Toxicity analysis indicated the low environmental toxicity of Rhodamine B degradation intermediates for Rye seeds and Sudangrass seeds germination and *** study displayed that AginS_(2)and Bi_(2)WO_(6)work as the primary photocatalyst to form·O_(2)−and ·OH,*** improved photocatalytic activity of the Bi_(2)WO_(6)/AginS_(2)S-scheme heterojunction was due to the im-proved light response range and intensified carrier separation ***,a S-scheme charge transfer mechanism including multiple charge transfer channels was *** work could provide an effective strategy for organic pollutants degradation in wastewater.

关键词： Photocatalysis S-scheme heterojunction AginS_(2) Bi_(2)WO_(6) Toxicity experiments

Soliton resolution and asymptotic stability of N-solutions for the defocusing Kundu–eckhaus equation with nonzero boundary conditions

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Communications in Theoretical Physics 2024年第1期76卷 1-6页

作者： engui fan Yanxi Zhang School of Mathematical Sciences and Key Laboratory of Mathematics for Nonlinear Science Fudan UniversityShanghai200433China Tianjin Xinhua High School No.99 machang RoadTianjin300204China

in this paper,we address interesting soliton resolution,asymptotic stability of N-soliton solutions and the Painleve asymptotics for the Kundu-eckhaus(Ke)equation with nonzero boundary conditions iq_(t)+q_(xx)-2(l|q|^(2)-1)q+4β^(2)(lql^(4)-1)q+4iβ(lql^(2))_(x)q=0,q(x,0)=q_(0)(x)-±1,x→±∞.The key to proving these results is to establish the formulation of a Riemann-Hilbert(RH)problem associated with the above Cauchy problem and find its connection with the RH problem of the defocusing NLS *** the■-steepest descent method and the results of the defocusing NLS equation,we find complete leading order approximation formulas for the defocusing Ke equation on the whole(x,t)half-plane including soliton resolution and asymptotic stability of N-soliton solutions in a solitonic region,Zakharov-Shabat asymptotics in a solitonless region and the Painlevéasymptotics in two transition regions.

关键词： defocusing Kundu-eckhaus equation Riemann-Hilbert problems steepest descent method soliton resolution asymptotic stability Painleve transcendents

Simplified seismic scenario analysis of existing masonry buildings accounting for local site effects

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Frontiers of Structural and Civil engineering 2024年第2期18卷 309-318页

作者： Ayşe e.ÖZSOYÖZBAY işıl SANRi KARAPiNAR Zehra N.KUTLU ismail e.KiLiÇ Department of Civil engineering Maltepe UniversityIstanbul 34857Turkey School of engineering and Construction Oryx Universal CollegeDoha 12253Qatar

This study discusses the effects of local sites and hazard amplification on the seismic vulnerability assessment of existing masonry *** this context,a rapid seismic evaluation procedure was implemented on an old masonry building stock in the historical center Galata,located inistanbul,to determine the seismic risk priority of the built *** scenarios were generated for all soil classes,different moment magnitudes,and source-to-site distances to obtain more accurate results for the seismic vulnerability assessment of the studied building ***,damage distributions estimated under nine different scenarios with/without site effects were compared and illustrated in maps to discuss changes in vulnerability owing to amplification *** this study,by re-examining the rapid seismic evaluation procedure by including geo-hazard-based assessment,the importance of site effects on the vulnerability and risk assessment of built heritage was *** proposed framework integrating field data and local site effects is believed to advance the current applications for vulnerability assessment of masonry buildings and provide an improvement in the application of rapid seismic assessment procedures with more reliable results.

关键词： masonry buildings seismic vulnerability assessment cultural heritage local site effect

Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains

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Plant Diversity 2024年第3期46卷 321-332页

作者： Jieshi Tang Xiaoyan fan Richard i.Milne Heng Yang Wenjing Tao Xinran Zhang Mengyun Guo Jialiang Li Kangshan Mao Key Laboratory of Bio-Resource and eco-environment of Ministry of education College of Life SciencesState Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610065PR China institute of Molecular Plant Sciences University of EdinburghEdinburgh EH93JHUK School of ecology and environment Tibet UniversityLhasa 850000PR China

Biogeographical barriers to gene flow are central to plant *** east Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across *** we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern *** and migration hypotheses were tested using coalescent-based *** historical gene flow was observed between the western and eastern groups of ***,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central ***-borne pollen and seeds may have facilitated the dispersal of *** following prevalent northwest winds in the *** also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of *** niche modeling suggested that *** has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 *** phylogeographic pattern of *** reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate *** study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

关键词： Chloroplast DNA Microsatellite Phylogeographic break Populus rotundifolia Quaternary history Wind direction

Prediction of subsurface settlement induced by shield tunnelling in sandy cobble stratum

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Journal of Rock Mechanics and Geotechnical engineering 2024年第1期16卷 192-212页

作者： fan Wang Xiuli Du Pengfei Li Key Laboratory of Urban Security and Disaster engineering Ministry of EducationBeijing University of TechnologyBeijing100124China

This study focuses on the analytical prediction of subsurface settlement induced by shield tunnelling in sandy cobble stratum considering the volumetric deformation modes of the soil above the tunnel crown.A series of numerical analyses is performed to examine the effects of cover depth ratio(C/D),tunnel volume loss rate(h t)and volumetric block proportion(VBP)on the characteristics of subsurface settle-ment trough and soil volume *** the ground loss variation with depth,three modes are deduced from the volumetric deformation responses of the soil above the tunnel ***,analytical solutions to predict subsurface settlement for each mode are presented using stochastic medium *** influences of C/D,h t and VBP on the key parameters(i.e.B and N)in the analytical expressions are discussed to determine the fitting formulae of B and ***,the proposed analytical solutions are validated by the comparisons with the results of model test and numerical *** show that the fitting formulae provide a convenient and reliable way to evaluate the key ***,the analytical solutions are reasonable and available in predicting the subsurface settlement induced by shield tunnelling in sandy cobble stratum.

关键词： Shield tunnelling Sandy cobble stratum Subsurface settlement Volumetric deformation mode Stochastic medium theory

estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy

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international Journal of Mining Science and Technology 2024年第2期34卷 137-148页

作者： Chuangbing Zhou Zuyang Ye Chi Yao Xincheng fan Feng Xiong School of infrastructure engineering Nanchang UniversityNanchang 330031China b School of Resource and environmental engineering Wuhan University of Science and TechnologyWuhan 430081China School of engineering China University of GeosciencesWuhan 430074China

With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different *** with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture *** to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip *** a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors.

关键词： 3D fracture network Geological entropy Directional entropic scale Anisotropy Hydraulic conductivity

Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros i.Theocharis Nikolaos C.Koukouzas ioannis e.Zevgolis Chemical Process&energy Resources institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** creation and sustainability of these lakes are significantly affected by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and efficiently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually decreases until the reservoir reaches a critical level of 10%e40%of the total height;it then increases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts Critical level

Machine Learning Analysis of impact of Western US Fires on Central US Hailstorms

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Advances in Atmospheric Sciences 2024年第7期41卷 1450-1462页

作者： Xinming LiN Jiwen fan Yuwei ZHANG ZJason HOU Pacific Northwest National Laboratory RichlandWA 99354USA Argonne National Laboratory LemontIL 60439USA

Fires,including wildfires,harm air quality and essential public services like transportation,communication,and *** fires can also influence atmospheric conditions,including temperature and aerosols,potentially affecting severe convective ***,we investigate the remote impacts of fires in the western United States(WUS)on the occurrence of large hail(size:≥2.54 cm)in the central US(CUS)over the 20-year period of 2001–20 using the machine learning(ML),Random Forest(RF),and extreme Gradient Boosting(XGB)*** developed RF and XGB models demonstrate high accuracy(>90%)and F1 scores of up to 0.78 in predicting large hail occurrences when WUS fires and CUS hailstorms coincide,particularly in four states(Wyoming,South Dakota,Nebraska,and Kansas).The key contributing variables identified from both ML models include the meteorological variables in the fire region(temperature and moisture),the westerly wind over the plume transport path,and the fire features(i.e.,the maximum fire power and burned area).The results confirm a linkage between WUS fires and severe weather in the CUS,corroborating the findings of our previous modeling study conducted on case simulations with a detailed physics model.

关键词： wildfire severe convective storm hailstorm machine learning

Huoxue Jiedu Huayu recipe(活血解毒化瘀方) inhibits macrophage-secreted vascular endothelial growth factor-a on angiogenesis and alleviates renal fibrosis in the contralateral kidneys of unilateral ureteral obstruction rats

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Journal of Traditional Chinese Medicine 2024年第3期44卷 458-467页

作者： GAO Xiaomeng QiANG Panpan CHANG Jingyue.fan Lili YANG fan XU Qingyou Graduate School Hebei University of Chinese Medicine Hebei Key Laboratory of integrative Medicine on Liver-Kidney Patterns Hebei University of Chinese Medicine institute of integrative Medicine Hebei University of Chinese Medicine

OBJeCTiVe: To elucidate the mechanism by which Huoxue Jiedu Huayu recipe( 活血解毒化瘀方, HJHR) regulates angiogenesis in the contralateral kidney of unilateral ureteral obstruction(UUO) rats and the mechanism by which it reduces of renal fibrosis. MeTHODS: Male Wistar rats were randomly divided into 4 groups: the sham group, UUO group(180 d of left ureter ligation), UUO plus eplerenone(ePL) group, and UUO plus HJHR group. After 180 d of oral drug administration, blood and contralateral kidneys were collected for analysis. Angiogenesis-and fibrosis-related indexes were detected. ReSULTS: HJHR and ePL improved structural damage and renal interstitial fibrosis in the contralateral kidney and reduced the protein expression levels of α-smooth muscle actin(α-SMA), vimentin and collagen i. Moreover, these treatments could reduce the expression of vascular endothelial growth factor-A(VeGFA) by inhibiting the infiltration of macrophages. Furthermore, HJHR and ePL significantly reduced the expression of CD34 and CD105 by downregulating VeGFA production, which inhibited angiogenesis. Finally, the coexpressions of CD34, CD105 and α-SMA were decreased in the HJHR and ePL groups, indicating that endothelial-to-mesenchymal transition was inhibited. CONCLUSiONS: These findings confirm that HJHR alleviates contralateral renal fibrosis by inhibiting VeGFAinduced angiogenesis, encourage the use of HJHR against renal interstitial fibrosis and provide a theoretical basis for the clinical management of patients with CKD.

关键词： Huoxue Jiedu Huayu recipe aldosterone epithelial-mesenchymal transition eplerenone receptors, mineralocorticoid unilateral ureteral obstruction

A Survey of edge Caching:Key issues and Challenges

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Tsinghua Science and Technology 2024年第3期29卷 818-842页

作者： Hanwen Li Mingtao Sun fan Xia Xiaolong Xu Muhammad Bilal School of Computer Science Nanjing University of Information Science and TechnologyNanjing 210044China Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyWeifang 262700China Reading Academy Nanjing University of Information Science and TechnologyNanjing 210044China School of Software Nanjing University of Information Science and TechnologyNanjing 210044China Department of Computer engineering Hankuk University of Foreign StudiesYongin-si 17035Republic of Korea

With the rapid development of mobile communication technology and intelligent applications,the quantity of mobile devices and data traffic in networks have been growing exponentially,which poses a great burden to networks and brings huge challenge to servicing user *** caching,which utilizes the storage and computation resources of the edge to bring resources closer to end users,is a promising way to relieve network burden and enhance user *** this paper,we aim to survey the edge caching techniques from a comprehensive and systematic *** first present an overview of edge caching,summarizing the three key issues regarding edge caching,i.e.,where,what,and how to cache,and then introducing several significant caching *** then carry out a detailed and in-depth elaboration on these three issues,which correspond to caching locations,caching objects,and caching strategies,*** particular,we innovate on the issue“what to cache”,interpreting it as the classification of the“caching objects”,which can be further classified into content cache,data cache,and service ***,we discuss several open issues and challenges of edge caching to inspire future investigations in this research area.

关键词： edge caching edge computing caching location caching object caching strategy 5G networkarchitecture internet of Things(ioT)