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Spatio-temporal variability of surface chlorophyll a in the Yellow Sea and the East China Sea based on reconstructions of satellite data of 2001-2020

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Journal of Oceanology and Limnology 2024年第2期42卷 390-407页

作者： Weichen XIE Tao WANG Wensheng JIANG key laboratory of Marine Environment and Ecology Ocean University of ChinaQingdao 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China

Chlorophyll-a(Chl-a)concentration is a primary indicator for marine environmental *** spatio-temporal variations of sea surface Chl-a concentration in the Yellow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS Level 3 products with the data interpolation empirical orthogonal function(DINEOF)*** reconstructed results by interpolating the combined MODIS daily+8-day datasets were found better than those merely by interpolating daily or 8-day ***-a concentration in the YS and the ECS reached its maximum in spring,with blooms occurring,decreased in summer and autumn,and increased in late autumn and early *** performing empirical orthogonal function(EOF)decomposition of the reconstructed data fields and correlation analysis with several potential environmental factors,we found that the sea surface temperature(SST)plays a significant role in the seasonal variation of Chl a,especially during spring and *** increase of SST in spring and the upper-layer nutrients mixed up during the last winter might favor the occurrence of spring *** high sea surface temperature(SST)throughout the summer would strengthen the vertical stratification and prevent nutrients supply from deep water,resulting in low surface Chl-a *** sea surface Chl-a concentration in the YS was found decreased significantly from 2012 to 2020,which was possibly related to the Pacific Decadal Oscillation(PDO).

关键词： chlorophyll a(Chl a) data interpolation empirical orthogonal function(DINEOF) empirical orthogonal function(EOF)analysis Yellow Sea East China Sea

维普期刊数据库

Impact factors and pathways of halonitromethanes formation from aspartic acid during LED-UV_(265)/chlorine disinfection

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 129-144页

作者： Liangwen Zhu Tao Wang Qian Tang Qing Wang Lin Deng Jun Hu Chaoqun Tan Rajendra Prasad Singh key laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education School of Civil EngineeringSoutheast UniversityNanjing 211189China College of Environment Zhejiang University of TechnologyHangzhou 310014China

Light emitting diode (LED-UV)/chlorine disinfection can replace UV/chlorine disinfection in wastewater treatment plants and water supply plants. Halonitromethanes (HNMs) are a class of novel nitrogenous disinfection by-products, which are characterized by higher cytotoxicity and genotoxicity than regulated disinfection by-products. Herein, the impact factors and pathways of HNMs formation from aspartic acid (ASP) were investigated during LED-UV_(265)/chlorine disinfection. The results showed that three types of chlorinated-HNMs (Cl-HNMs) were found during LED-UV265/chlorine disinfection, and their concentrations increased first and then declined as the reaction progressed. Cl-HNMs yields increased with increasing LED-UV_(265) intensity, free chlorine dosage, and ASP concentration, which declined with increasing pH (6.0–8.0). Meantime, the important impact of the coexisting ions contained in water matrices on HNMs formation from ASP was observed during LED-UV_(265)/chlorine disinfection. It was found that copper ions (Cu^(2+)) promoted Cl-HNMs formation. Furthermore, when bromide (Br–) appeared during LED-UV265/chlorine disinfection, nine types of HNMs were detected simultaneously. Moreover, Br– not only converted Cl-HNMs toward brominated (chlorinated)-HNMs and brominated-HNMs but also showed a marked effect on HNMs concentrations and species. Subsequently, the possible pathways of HNMs formation from ASP were proposed during LED-UV_(265)/chlorine disinfection. At last, it was proved that the formation trends of HNMs obtained in the real waters were similar to those in simulated waters. This work elaborated on the influence factors and pathways of HNMs formation, which is conducive to controlling the HNMs produced during LED-UV_(265)/chlorine disinfection.

关键词： LED-UV265 chlorine HNMs Aspartic acid Bromide Copper ions

High nitrogen fertilizer input enhanced the microbial network complexity in the paddy soil

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Soil Ecology Letters 2024年第2期6卷 97-109页

作者： Yanan Chen Yan Li Tianyi Qiu Haoran He Ji Liu Chengjiao Duan Yongxing Cui Min Huang Chunyan Wu Linchuan Fang The Research Center of Soil and water Conservation and Ecological Environment Chinese Academy of Sciences and Ministry of EducationYangling712100China State key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation CAS and MWRYangling712100China University of Chinese Academy of Sciences Beijing100049China Institute of Environment Resource and Soil Fertilizer Zhejiang Academy of Agricultural SciencesHangzhou310021China College of Natural Resources and Environment Northwest A&F UniversityYangling712100China Hubei Province key laboratory for Geographical Process Analysis and Simulation Central China Normal UniversityWuhan430079China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland FisheriesBerlin12587Germany Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing100871China College of Resources and Environmental Engineering Wuhan University of TechnologyWuhan430070China CAS Center for Excellence in Quaternary Science and Global Change Xi’an710061China

N fertilizer altered bacterial community compositions by changing soil nutrients.•Bacterial ammonia oxidation became predominated with the increasing N rate.•Excessive N input caused the information of a more complex microbial network.•Intensified microbial competition by excessive N was due to negative link ***(N)fertilization drives the structure and function of soil microbial communities,which are crucial for regulating soil biogeochemical cycling and maintaining ecosystem *** the N fertilizer effects on soil microbial composition and diversity have been widely investigated,it is generally overlooked that ecosystem processes are carried out via complex associations among microbiome ***,we examined the effects of five N fertilization levels(0,135,180,225,and 360 kg N ha−1)on microbial co-occurrence networks and key functional taxa such as ammonia-oxidizers in paddy *** results showed that N addition altered microbial community composition,which were positively related to soil total N and available phosphorus(P)*** abundance of ammonia-oxidizing archaea(AOA)significantly decreased after N addition,whereas ammonia-oxidizing bacteria(AOB)increased in N360 *** with low-N group(N0 and N135),the high-N group(N225 and N360)shaped more complex microbial webs and thus improved the stability of the microbial *** least squares path modeling further revealed that N fertilizer had a higher effect on microbial network complexity in the high-N group(0.83)than the low-N group(0.49).Although there were more positive links across all microbial networks,the proportion of negative links significantly increased in the high-N network,suggesting that excess N addition aggravated the competition among microbial *** these interactions between microbial communities and N fertilization advances our understanding of biogeochemical processes in paddy soils and their effects on nutrient supply to

关键词： nitrogen fertilizer paddy soil co-occurrence network microbial interaction

A Novel Defender-Attacker-Defender Model for Resilient Distributed Generator Planning with Network Reconfiguration and Demand Response

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Energy Engineering 2024年第5期121卷 1223-1243页

作者： Wenlu Ji Teng Tu Nan Ma Nanjing Power supply Company State Grid Jiangsu Electric Power Co.Ltd.Nanjing210019China

To improve the resilience of a distribution system against extreme weather,a fuel-based distributed generator(DG)allocation model is proposed in this *** this model,the DGs are placed at the planning *** an extreme event occurs,the controllable generators form temporary microgrids(MGs)to restore the load ***,a demand response program(DRP)mitigates the imbalance between the power supply and demand during extreme *** cope with the fault uncertainty,a robust optimization(RO)method is applied to reduce the long-term investment and short-term operation *** optimization is formulated as a tri-level defenderattacker-defender(DAD)*** the first level,decision-makers work out the DG allocation scheme;at the second level,the attacker finds the optimal attack strategy with maximum damage;and at the third level,restoration measures,namely distribution network reconfiguration(DNR)and demand response are *** problem is solved by the nested column and constraint generation(NC&CG)method and the model is validated using an IEEE 33-node *** studies validate the effectiveness and superiority of the proposed model according to the enhanced resilience and reduced cost.

关键词： Distribution system resilience defender-attacker-defender distributed generator demand response microgrids formation

Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2024年

作者： Yumin AI Massimo CHIARADIA Chao WU Huayong CHEN key laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial key laboratory of Mineral Physics and Materials

Porphyry copper deposits (PCDs) supply the majority of the world’s copper (Cu) as well as significant amounts of molybdenum (Mo) and gold (Au). The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium (V) to scandium (Sc) and its correlation with the oxygen fugacity (f O) of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number(Mg#) at the onset of magnetite fractionation is strongly positively correlated with f O of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts (<20 km), which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On th

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A Disturbance Localization Method for Power System Based on Group Sparse Representation and Entropy Weight Method

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Energy Engineering 2024年第8期121卷 2275-2291页

作者： Zeyi Wang Mingxi Jiao Daliang Wang Minxu Liu Minglei Jiang He Wang Shiqiang Li Changchun Power supply Company State Grid Jilin Electric Power Co.Ltd.Changchun130021China Economic and Technical Research Institute State Grid Jilin Electric Power Co.Ltd.Changchun130022China key laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Northeast Electric Power UniversityJilin132012China

This paper addresses the problem of complex and challenging disturbance localization in the current power system operation environment by proposing a disturbance localization method for power systems based on group sparse representation and entropy weight *** different electrical quantities are selected as observations in the compressed sensing *** entropy weighting method is employed to calculate the weights of different observations based on their relative disturbance ***,by leveraging the topological information of the power system and pre-designing an overcomplete dictionary of disturbances based on the corresponding system parameter variations caused by disturbances,an improved Joint Generalized Orthogonal Matching Pursuit(J-GOMP)algorithm is utilized for *** reconstructed sparse vectors are divided into three *** at least two parts have consistent node identifiers,the node is identified as the disturbance *** the node identifiers in all three parts are inconsistent,further analysis is conducted considering the weights to determine the disturbance *** results based on the IEEE 39-bus system model demonstrate that the proposed method,utilizing electrical quantity information from only 8 measurement points,effectively locates disturbance positions and is applicable to various disturbance types with strong noise resistance.

关键词： Disturbance location compressed sensing group sparse representation entropy power method GOMP algorithm

Butler matrix enabled multi-beam optical phased array for two-dimensional beam-steering and ranging

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Photonics Research 2024年第5期12卷 912-920页

作者： ZUOYU ZHOU WEIHAN XU CHUXIN LIU RUIYANG XU CHEN ZHU XINHANG LI LIANGJUN LU JIANPING CHEN LINJIE ZHOU State key laboratory of Advanced Optical Communication Systems and Networks Shanghai Key Laboratory of Navigation and Location ServicesShanghai Institute for Advanced Communication and Data ScienceDepartment of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China SJTU-Pinghu Institute of Intelligent Optoelectronics Pinghu 314200China State Grid Sichuan Electric Power Company Chengdu Xinjin Power supply Branch Xinjin 611430China

Based on the wavelength transparency of the Butler matrix(BM)beamforming network,we demonstrate a multibeam optical phased array(MOPA)with an emitting aperture composed of grating couplers at a 1.55μm pitch for wavelength-assisted two-dimensional *** device is capable of simultaneous multi-beam operation in a field of view(FOV)of 60°×8°in the phased-array scanning axis and the wavelength-tuning scanning axis,*** typical beam divergence is about 4°on both *** multiple linearly chirped lasers,multibeam frequency-modulated continuous wave(FMCW)ranging is realized with an average ranging error of 4 cm.A C-shaped target is imaged for proof-of-concept 2D scanning and ranging.

关键词： optical tuning beam

维普期刊数据库

CRBFT:A Byzantine Fault-Tolerant Consensus Protocol Based on Collaborative Filtering Recommendation for Blockchains

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Computers, Materials & Continua 2024年第7期80卷 1491-1519页

作者： Xiangyu Wu Xuehui Du Qiantao Yang Aodi Liu Na Wang Wenjuan Wang He’nan Province key laboratory of Information Security Information Engineering UniversityZhengzhou450000China School of Cyber Science Engineering Zhengzhou UniversityZhengzhou450000China

Blockchain has been widely used in finance,the Internet of Things(IoT),supply chains,and other scenarios as a revolutionary *** protocol plays a vital role in blockchain,which helps all participants to maintain the storage state ***,with the improvement of network environment complexity and system scale,blockchain development is limited by the performance,security,and scalability of the consensus *** address this problem,this paper introduces the collaborative filtering mechanism commonly used in the recommendation system into the Practical Byzantine Fault Tolerance(PBFT)and proposes a Byzantine fault-tolerant(BFT)consensus protocol based on collaborative filtering recommendation(CRBFT).Specifically,an improved collaborative filtering recommendation method is designed to use the similarity between a node’s recommendation opinions and those of the recommender as a basis for determining whether to adopt the recommendation *** can amplify the recommendation voice of good nodes,weaken the impact of cunningmalicious nodes on the trust value calculation,andmake the calculated resultsmore *** addition,the nodes are given voting power according to their trust value,and a weight randomelection algorithm is designed and implemented to reduce the risk of *** experimental results show that CRBFT can effectively eliminate various malicious nodes and improve the performance of blockchain systems in complex network environments,and the feasibility of CRBFT is also proven by theoretical analysis.

关键词： Blockchain consensus byzantine fault-tolerant collaborative filtering trust

Evaluation of Multi-Temporal-Spatial Scale Adjustment Capability and Cluster Optimization Operation Method for Distribution Networks with Distributed Photovoltaics

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Energy Engineering 2024年第9期121卷 2655-2680页

作者： Jiaxin Qiao Yuchen Hao Yingqi Liao Fang Liang Jing Bian Northeast Electric Power University Key Laboratory of Modern Power System Simulation and Control&Renewable Energy TechnologyMinistry of EducationJilin132011China State Grid Jiangsu Electric Power Co. Ltd.Power Dispatch Control CenterNanjing210017China State Grid Jiangsu Electric Power Co. Ltd.Nanjing Power Supply BranchPower Dispatch Control CenterNanjing210019China

Themassive integration of high-proportioned distributed photovoltaics into distribution networks poses significant challenges to the flexible regulation capabilities of distribution *** accurately assess the flexible regulation capabilities of distribution stations,amulti-temporal and spatial scale regulation capability assessment technique is proposed for distribution station areas with distributed photovoltaics,considering different geographical locations,coverage areas,and response ***,the multi-temporal scale regulation characteristics and response capabilities of different regulation resources in distribution station areas are analyzed,and a resource regulation capability model is established to quantify the adjustable range of different regulation *** this basis,considering the limitations of line transmission capacity,a regulation capability assessment index for distribution stations is proposed to evaluate their regulation ***,considering different geographical locations and coverage areas,a comprehensive performance index based on electrical distance modularity and active power balance is established,and a cluster division method based on genetic algorithms is proposed to fully leverage the coordination and complementarity among nodes and improve the active power matching degree within ***,an economic optimization model with the objective of minimizing the economic cost of the distribution station is established,comprehensively considering the safety constraints of the distribution network and the regulation constraints of *** model can provide scientific guidance for the economic dispatch of the distribution station ***,case studies demonstrate that the proposed assessment and optimization methods effectively evaluate the regulation capabilities of distribution stations,facilitate the consumption of distributed photovoltaics,and enhance the economic efficiency of th

关键词： Distributed photovoltaic distribution station area assessment of adjustment capacity line transmission capacity economic optimization