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Spatial and temporal variations of water quality in Cao-E River of eastern China

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Journal of Environmental Sciences 2006年第4期18卷 680-688页

作者： chen ding-jiang LU Jun YUAN Shao-feng JIN Shu-quan SHEN Ye-na Ministry of Education Key Lab of Environment Remediation and Ecological Health. Zhejiang University Hangzhou 310029 China Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 China

Evaluation and analysis of water quality variations were performed with integrated consideration of water quality parameters, hydrological-meteorologic and anthropogenic factors in Cao-E River, Zhejiang Province of China. Cao-E River system has been polluted and the water quality of some reaches are inferior to Grade V according to National Surface Water Quality Standard of China （GB2002）. However, mainly polluted indices of each tributary and mainstream are different. Total nitrogen （TN） and total phosphorus （TP） in the water are the main polluted indices for mainstream that varies from 1.52 to 45.85 mg/L and 0.02 to 4.02 mg/L, respectively. TN is the main polluted indices for Sub-watershed Ⅰ, Ⅱ, Ⅳ and Ⅴ（0.76 to 18.27 mg/L）. BOD5 （0.36 to 289.5 mg/L）, CODMn （0.47 to 78.86 mg/L）, TN （0.74 to 31.09 mg/L） and TP （0 to 3.75 mg/L） are the main polluted indices for Sub-watershed Ⅲ. There are tow pollution types along the river including nonpoint source pollution and point source pollution types. Remarkably temporal variations with a few spatial variations occur in nonpoint pollution type reaches （including mainstream, Sub-watershed Ⅰ and Ⅱ） that mainly drained by arable field and/or dispersive rural dwelling district, and the maximum pollutant concentration appears in flooding seasons. It implied that the runoff increases the pollutant concentration of the water in the nonpoint pollution type reaches. On the other hand, remarkably spatial variations occur in the point pollution type reaches （include Sub-watershed Ⅲ, Ⅳ and Ⅴ） and the maximum pollutant concentration appears in urban reaches. The runoff always decreases the pollutant concentration of the river water in the seriously polluted reaches that drained by industrial point sewage. But for the point pollution reaches resulted from centralized town domestic sewage pipeline and from frequent shipping and digging sands, rainfall always increased the concentration of pollutant （TN） in the river water too. Pollution cont

关键词： spatial and temporal variations water quality point pollution nonpoint pollution Cao-E River

Titanium-Promoted Rh-Mn-Li/SiO_(2) for C_(2)-Oxygenates Synthesis from Syngas: Effect of Low Titanium Loading

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Journal of Natural Gas Chemistry 2005年第4期14卷 199-206页

作者： Weimiao chen Yunjie ding Dahao jiang Zhendong Pan Hongyuan Luo Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

Addition of small amounts of Ti oxide to Rh-Mn-Li/SiO2 catalysts unexpectedly results in an increase in their activity for C2-oxygenates production from syngas. Continuously increasing Ti loading depresses catalyst activity. The effect of Ti at low level on the catalytic properties in the CO/H2 reaction has been studied by various techniques. The characterization results indicate that the existence of Ti species has no effect on the ability of Rh to dissociate CO molecules and on the Rh dispersion. On the other hand, it is shown that trace amount of Ti strengthens the adsorption of CO and increases the amount of strongly adsorbed CO that can be hydrogenated and therefore improves the activity. The RhMn interaction intensity, which can be regulated by Ti doping, seems to be the main reason to achieve higher yield of the desired reaction products.

关键词： rhodium titanium CO hydrogenation C2-oxygenates syngas conversion

Response of Stream Pollution Characteristics to Catchment Land Cover in Cao-E River Basin, China

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Pedosphere 2011年第1期21卷 115-123页

作者： SHEN Ye-Na LUE Jun chen ding-jiang SHI Yi-Ming Department of Natural Resources College of Environmental Science and Natural Resources Zhejiang University Hangzhou 310029 (China) China Ministry of Education Key Lab of Environmental Remediation and Ecological Health Zhejiang University Hangzhou 310029 (China) Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

This study addressed the relationship of river water pollution characteristics to land covers and human activities in the catchments in a complete river system named Cao-E River in eastern *** on the hydrogeochemical data collected monthly over a period of 3 years,cluster analysis(CA) and principal component analysis(PCA) were adopted to categorize the river reaches and reveal their pollution *** to the differences of water quality in the river reaches and land use patterns and average population densities in their catchments,the whole river system could be categorized into three groups of river reaches,i.e.,non-point sources pollution reaches(NPSPR),urban reaches(UR) and mixed sources pollution reaches(MSPR).In UR and MSPR,the water quality was mainly impacted by nutrient and organic pollution,while in NPSPR nutrient pollution was the main *** nitrate was the main nitrogen form in NPSPR and particulate phosphorus was the main phosphorus form in *** were no apparent trends for the variations of pollutant concentrations with increasing river flows in NPSPR and MSPR,while in UR the pollutant concentrations decreased with increasing river *** dry season was the critical period for water pollution control in ***,catchment land covers and human activities had significant impact on river reach water pollution type,nutrient forms and water quality responses to hydrological conditions,which might be crucial for developing strategies to combat water pollution in watershed scale.

关键词： cluster analysis hydrological conditions pollution factors principle component analysis water quality

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

Miyaoka-type inequalities for terminal threefolds with nef anti-canonical divisors

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Science China Mathematics 2025年第1期68卷 1-18页

作者： Masataka Iwai chen jiang Haidong Liu Department of Mathematics Graduate School of ScienceOsaka University Shanghai Center for Mathematical Sciences & School of Mathematical Sciences Fudan University Department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X） · c2（X）≠0,then c1（X） · c2（X） ≥ 1/252;if further X is not rationally connected,then c1（X） · c2（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dim X-2· c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness

Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method

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Energy Engineering 2025年第1期122卷 63-84页

作者： SuliangMa ZeqingMeng Mingxuan chen Yuan jiang School of Electrical and Control Engineering North China University of TechnologyBeijing100144China ChinaThree Gorges Technology Co. Ltd.Beijing100032China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China

In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is ***,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical *** deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s *** optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization *** proposed method better balances all optimization objective functions and reduces the impact of their *** the cost of BESS decreases by approximately 30%,its participation deepens by about 1 ***,if the price of the electrolyzer is less than 15￥/kWh or if the cost of the fuel cell drops below 4￥/kWh,their participation will increase *** study aims to provide a more reasonable approach to solving multi-objective optimization problems.

关键词： Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system

Lightweight Underwater Target Detection Using YOLOv8 with Multi-Scale Cross-Channel Attention

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Computers, Materials & Continua 2025年第1期82卷 713-727页

作者： Xueyan ding Xiyu chen Jiaxin Wang Jianxin Zhang School of Computer Science and Engineering Dalian Minzu UniversityDalian116600China Research Center of Multimodal Information Perception and Intelligent Processing Dalian Minzu UniversityDalian116600China

Underwater target detection is extensively applied in domains such as underwater search and rescue,environmental monitoring,and marine resource *** is crucial in enabling autonomous underwater robot operations and promoting ocean ***,low imaging quality,harsh underwater environments,and obscured objects considerably increase the difficulty of detecting underwater targets,making it difficult for current detection methods to achieve optimal *** order to enhance underwater object perception and improve target detection precision,we propose a lightweight underwater target detection method using You Only Look Once(YOLO)v8 with multi-scale cross-channel attention(MSCCA),named *** the proposed multiscale cross-channel attention module,multi-scale attention(MSA)augments the variety of attentional perception by extracting information from innately diverse sensory *** cross-channel strategy utilizes RepVGGbased channel shuffling(RCS)and one-shot aggregation(OSA)to rearrange feature map channels according to specific *** aggregates all features only once in the final feature mapping,resulting in the extraction of more comprehensive and valuable feature *** experimental results show that the proposed YOLOv8-UOD achieves a mAP50 of 95.67%and FLOPs of 23.8 G on the Underwater Robot Picking Contest 2017(URPC2017)dataset,outperforming other methods in terms of detection precision and computational cost-efficiency.

关键词： Deep learning underwater target detection attention mechanism

1980～2010年浙江某典型河流硝态氮通量对净人类活动氮输入的动态响应

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环境科学 2014年第8期35卷 2911-2919页

作者：张柏发陈丁江浙江大学环境与资源学院杭州310058 浙江大学污染环境修复与生态健康教育部重点实验室杭州310058

以浙江某典型流域为研究对象,基于1980～2010年的水质水量和氮源数据及LOADEST模型,估算了逐年河流NO-3-N通量和净人类活动氮输入(NANI),分析了河流NO-3-N通量和NANI的年际演化特征及其动态响应关系,探讨了每年NANI、滞留氮库、自然背... 详细信息

以浙江某典型流域为研究对象,基于1980～2010年的水质水量和氮源数据及LOADEST模型,估算了逐年河流NO-3-N通量和净人类活动氮输入(NANI),分析了河流NO-3-N通量和NANI的年际演化特征及其动态响应关系,探讨了每年NANI、滞留氮库、自然背景源对河流NO-3-N通量的贡献.结果表明,1980～2010年,河流NO-3-N通量和NANI总体上都呈现出先增后减的抛物线型变化趋势,均在1998年左右分别达到峰值5.74 kg·(hm2·a)-1和77.5 kg·(hm2·a)-1;过去31 a,河流NO-3-N通量和NANI分别净增加了～42%和～77%.化肥氮和大气氮沉降是NANI的主要来源,分别占了NANI的～48%和～40%.河流NO-3-N通量的年际变化不仅与NAIN(R2=0.27**)和化肥氮输入量(R2=0.32**)显著相关,而且与河流年均流量(R2=0.79**)或降雨量(R2=0.63**)具有更强的相关性,意味着河流NO-3-N的来源除了当年的NAIN,还受滞留氮库的影响.所建立的以NANI和流量为自变量的回归模型能很好地模拟河流NO-3-N通量变化(R2=0.94**).该模型预测结果显示,在NANI和流量分别降低30%的情况下,河流年均NO-3-N通量将分别减少～21%和～30%;每年的NANI、滞留氮库、自然背景源对河流当年NO-3-N通量的贡献率分别为～53%、～24%、～23%.河流NO-3-N通量长期的年际变化是NANI和水文要素共同作用的结果;但是,由于滞留氮库的影响,与源控制方式相比,增加"汇"景观应该能更加快速地削减河流NO-3-N通量.

关键词：硝态氮净人类活动氮输入滞留氮库动态响应河流

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中国乘用车塑料的动态物质流分析

中国环境科学 2020年第9期40卷 4106-4114页

作者：蒋晓斌江健陈定江周文戟朱兵清华大学化学工程系生态工业研究中心北京100084 清华大学循环经济研究院北京100084 挪威科技大学制造与土木工程系挪威约维克2815

结合行业信息并基于动态物质流模型,本文对1950~2050年间中国乘用车塑料流量与存量进行了历史测算与情景分析.历史测算表明:1950~2018年国内乘用车行业累计消耗了以聚丙烯(PP)、聚氨酯(PU)等为主的塑料3278万t,产生了337万t塑料废弃物;... 详细信息

结合行业信息并基于动态物质流模型,本文对1950~2050年间中国乘用车塑料流量与存量进行了历史测算与情景分析.历史测算表明:1950~2018年国内乘用车行业累计消耗了以聚丙烯(PP)、聚氨酯(PU)等为主的塑料3278万t,产生了337万t塑料废弃物;报废汽车拆解后的车用废塑料仅28%得到回收利用.针对未来情况,本文设计了乘用车保有量、单车塑料使用量两大关键因素下的不同情景组合.结果显示车用塑料存量及废塑料产生量将大幅增长,到2050年存量将达到0.7~2.7亿t,废塑料产生量将达到500~1600万t,汽车拆解和塑料再生等相关行业对此应充分关注.到2050年车用废塑料回收率若能提升至80%,将减少376万t/a的车用废塑料填埋或焚烧,显著减少环境风险.

关键词：动态物质流报废汽车塑料存量