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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 44-49页

作者：刘云才 ZHU chen School of Architecture and Materials Engineering Hubei Second Normal UniversityWuhan 430205China

Phosphate was removed from aqueous environment by corundum-hollow-spheres supported caclined hydrotalcite (cHT) thin films. Mg-Al-CO3 hydrotalcite (HT) thin films were deposited on corundumhollow-sphere substrates by hydrothermal homogeneous precipitation at 120℃for 30-240 min and cHT thin films were obtained by annealing of the HT thin films at 500℃for 180 min. Their crystal phase, morphology and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).The results show that homogeneous, well-crystallized and hierarchical flower-like thin films were deposited firmly on the surface of the corundum. The mechanism of nucleation and growth of the HT thin films was fitted well with the anion coordination polyhedron growth unit model. To determine the absorption of phosphate by this adsorbent, different bed depth (10-30 cm) and flow rate (1.0-3.0 m L/min) were examined by column experiments. The highest removal efficiency of phosphate amounted to 98.5%under optimum condition (pH=7.2). The adsorption capacity increased as the bed depth increased and decreased as the flow rate increased.

关键词： adsorption phosphate hydrotalcite corundum-hollow-sphere hydrothermal homogeneous precipitation thermal anneal

Dominant woody plant species recognition with a hierarchical model based on multimodal geospatial data for subtropical forests

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Journal of Forestry Research 2024年第3期35卷 111-130页

作者： Xin chen Yujun Sun State Forestry&Grassland Administration Key Laboratory of Forest Resources&Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China

Since the launch of the Google Earth Engine(GEE)cloud platform in 2010,it has been widely used,leading to a wealth of valuable ***,the potential of GEE for forest resource management has not been fully *** extract dominant woody plant species,GEE combined Sen-tinel-1(S1)and Sentinel-2(S2)data with the addition of the National Forest Resources Inventory(NFRI)and topographic data,resulting in a 10 m resolution multimodal geospatial dataset for subtropical forests in southeast *** and texture features,red-edge bands,and vegetation indices of S1 and S2 data were computed.A hierarchical model obtained information on forest distribution and area and the dominant woody plant *** results suggest that combining data sources from the S1 winter and S2 yearly ranges enhances accuracy in forest distribution and area extraction compared to using either data source ***,for dominant woody species recognition,using S1 winter and S2 data across all four seasons was *** terrain factors and removing spatial correlation from NFRI sample points further improved the recognition *** optimal forest extraction achieved an overall accuracy(OA)of 97.4%and a maplevel image classification efficacy(MICE)of 96.7%.OA and MICE were 83.6%and 80.7%for dominant species extraction,*** high accuracy and efficacy values indicate that the hierarchical recognition model based on multimodal remote sensing data performed extremely well for extracting information about dominant woody plant *** the results using the GEE application allows for an intuitive display of forest and species distribution,offering significant convenience for forest resource monitoring.

关键词： Google Earth Engine Sentinel Forest resource inventory data Dominant woody plant species Subtropics Model performance

A chaotic spiking backpropagation approach to brain learning

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National Science Review 2024年第6期11卷 83-84页

作者： Guanrong chen Department of Electrical Engineering City University of Hong Kong

Spiking neural networks (SNNs)[1] are known for their superior energy efficiency, achieved through spiking signal transmission that mirrors biological nervous systems, thus solving the unsustainable energy-consumption...

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数字劳动的社会主义解释可能——基于笕川村“电商一条街”的扩展个案研究

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开放时代 2024年第4期 160-183,M0008页

作者：赵月枝俞雅芸陈佳逸清华大学新闻与传播学院、马克思主义新闻学与新闻教育改革研究中心清华大学新闻与传播学院

数字劳动研究在成为学界热点议题后,陷入了概念使用混乱、分析框架重复、语境迁移不适用的三重困境。本文以跨文化传播政治经济研究为理论框架,对浙江省缙云县笕川村“电商一条街”进行扩展个案研究,发现的是不同于现有文献中所呈现的... 详细信息

数字劳动研究在成为学界热点议题后,陷入了概念使用混乱、分析框架重复、语境迁移不适用的三重困境。本文以跨文化传播政治经济研究为理论框架,对浙江省缙云县笕川村“电商一条街”进行扩展个案研究,发现的是不同于现有文献中所呈现的被动的、原子化的“数字劳动”,是对全球数字资本主义逻辑而言具有逆向性的、主动的、集体性的劳动。本文认为,数字劳动讨论应在马克思主义中国化理论与实践框架下构建另一种解释可能。首先,破除“资本/工人”二分法,关注囊括外部大资本、地方小资本、劳动者以及各级党政部门等四大主体;其次,在关注对抗性的同时,也应注意多元主体间的合作与依存面向;最后,打造数字劳动的中国自主知识体系不仅关乎劳动概念的马克思主义中国化、时代化理解,还关乎知识生产的社会主义立场自觉。

关键词：数字劳动农村电商跨文化传播政治经济学自主知识体系

Global optimization of double protograph LDPC codes for JSCC scheme

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Science China(Information Sciences) 2024年第6期67卷 455-456页

作者： Qiwang chen chen chen Yu-cheng HE Zhiping XU Xiamen Key Laboratory of Mobile Multimedia Communications College of Information Science and EngineeringHuaqiao University Key Laboratory of Underwater Acoustic Communication and Marine Information Technology (Xiamen University) Ministry of Education School of Ocean Information Engineering Jimei University

A double low-density parity-check (D-LDPC) coding system was proposed in[1]as a typical joint source-channel coding(JSCC) scheme[1–5].In this system,two LDPC coding matrices perform source and channel coding,*** important concept in a D-LDPC coding system is the introduction of a linking matrix between the check nodes (CNs)of the source coding matrix and the variable nodes (VNs) of the channel LDPC coding matrix.

关键词： JOINT SOURCE DESIGN

Regulating Anderson localization with structural defect disorder

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Chinese Physics B 2024年第10期33卷 102-107页

作者： Mouyang cheng Haoxiang chen Ji chen School of Physics Peking UniversityBeijing 100871China Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials Peking UniversityBeijing 100871China Frontiers Science Center for Nano-Optoelectronics Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

Localization due to disorder has been one of the most intriguing theoretical concepts that evolved in condensed matter ***,we expand the theory of localization by considering two types of disorders at the same time,namely,the original Anderson’s disorder and the structural defect disorder,which has been suggested to be a key component in recently discovered two-dimensional amorphous *** increasing the degree of both disorders could induce localization of wavefunction in real space,we find that a small degree of structural defect disorder can significantly enhance the *** the degree of structural defect disorder increases,localized states quickly appear within the extended phase to enter a broad crossover region with mixed *** establish two-dimensional diagrams for the wavefunction localization and conductivity to highlight the interplay between the two types of *** theoretical model provides a comprehensive understanding of localization in two-dimensional amorphous materials and highlights the promising tunability of their transport properties.

关键词： Anderson localization structural defect disorder electronic transport properties

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng chen Jie chen Xunchang John ZHANG Peiyi PENG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China USDA-ARS Oklahoma and Central Plains Agricultural Research Center El Reno OK 73036USA Southwest Research Institute for Hydraulic and Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016China

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***,accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in *** this study,a data fusion method based on Convolutional Neural Networks(CNN)is used to fuse the hydrogen isotopic composition(δ^(2)H_(p))of observations and isotope-equipped general circulation model(iGCM)simulations.A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50-60 km is established for East China for the 1969-2017 *** to building the isoscape,the performance of three data fusion methods(DFMs)and two bias correction methods(BCMs)is *** results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a *** fusion methods based on back propagation and long short-term memory neural network perform similarly,while slightly outperforming the bias correction ***,the CNN method is used to generate the hydrogen isoscape,and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this *** generated isoscape shows similar spatial and temporal distribution characteristics to *** general,the distribution pattern of δ^(2)H_(p) is consistent with the temperature effect in northern China,and consistent with the precipitation amount effect in southern *** trend of the δ^(2)H_(p) time series is consistent with that of observed precipitation and ***,the generated isoscape effectively reproduces the observations,and has the characteristics of time continuity and relative spatial regularity,which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

Double Moving Extremes Ranked Set Sampling Design

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 75-90页

作者： Meng chen Wang-xue chen Rui Yang Department of Mathematics and Statistics Jishou UniversityJishou416000China

The traditional simple random sampling(SRS)design method is inefficient in many *** proposed some new designs to increase *** this paper,as a variation of moving extremes ranked set sampling(MERSS),double MERSS(DMERSS)is proposed and its properties for estimating the population mean are *** turns out that,when the underlying distribution is symmetric,DMERSS gives unbiased estimators of the population ***,it is found that DMERSS is more efficient than the SRS and MERSS methods for usual symmetric distributions(normal and uniform).For asymmetric distributions considered in this study,the DMERSS has a small bias and it is more efficient than SRS for usual asymmetric distribution(exponential)for small sample sizes.

关键词： double moving extremes ranked set sampling symmetric distribution efficiency

Revealing Tissue Heterogeneity and Spatial Dark Genes from Spatially Resolved Transcriptomics by Multiview Graph Networks

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Research 2024年第2期6卷 629-645页

作者： Ying Li Yuejing Lu chen Kang Peiluan Li Luonan chen School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China Longmen Laboratory LuoyangHenan471003China Key Laboratory of Systems Biology Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai201100China Key Laboratory of Systems Health Science of Zhejang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China School of Life Science and Technology ShanghaiTech UniversityShanghai201100.China

Spatially resolved transcriptomics(SRT)is capable of comprehensively characterizing gene expression patterns and providing an unbiased image of spatial *** fully understand the organizational complexity and tumor immune escape mechanism,we propose stMGATF,a multiview graph attention fusion model that integrates gene expression,histological images,spatial location,and gene *** better extract information,stMGATF exploits SimCLRv2 for visual feature exaction and employs edge feature enhanced graph attention networks for the learning potential embedding of each view.A global attention mechanism is used to adaptively integrate 3 views to obtain low-dimensional *** to diverse SRT datasets,stMGATF is robust and outperforms other methods in detecting spatial domains and denoising data even with different resolutions and *** particular,stMGATF contributes to the elucidation of tissue heterogeneity and extraction of 3-dimensional expression ***,considering the associations between genes in tumors,stMGATF can identify the spatial dark genes ignored by traditional methods,which can be used to predict tumor-driving transcription factors and reveal tumor immune escape mechanisms,providing theoretical evidence for the development of new immunotherapeutic strategies.

关键词： Spatial integrate driving

Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China

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Journal of Environmental Sciences 2024年第4期138卷 561-571页

作者： Ziyi Lin Xiaolong Fan Gaojie chen Youwei Hong Mengren Li Lingling Xu Baoye Hu chen Yang Yanting chen Zhiqian Shao Jinsheng chen Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy ofSciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Minnan Normal University Zhangzhou 363000China

To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,*** concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and *** on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping *** to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace *** the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain *** risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future.

关键词： PM_(2.5)-bound trace elements Seasonal variations Source appointment Health risks Traffic-related source