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Carrier phase shifted SPWM based on current sourced multi-modular converter for active power filter 被引量:5
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作者 王立乔 李建林 张仲超 《Journal of Zhejiang University Science》 EI CSCD 2004年第7期861-866,共6页
A novel current-source active power filter (APF) based on multi-modular converter with carrier phase-shifted SPWM (CPS-SPWM) technique is proposed. With this technique, the effect of equivalent high switching frequenc... A novel current-source active power filter (APF) based on multi-modular converter with carrier phase-shifted SPWM (CPS-SPWM) technique is proposed. With this technique, the effect of equivalent high switching frequency con-verter is obtained with low switching frequency converter. It is very promising in current-source APF that adopt super-conducting magnetic energy storage component. 展开更多
关键词 Current sourced multi-modular converter Carrier phase shifted SPWM Active power filter
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Technical Analysis of Freshwater Use as Part of a Responsibly Sourced Gas ESG Strategy
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作者 Finlay Carlson Huishu Li +2 位作者 Asma Hanif Josh Zier Kenneth Carlson 《Journal of Water Resource and Protection》 2022年第3期292-303,共12页
The Unconventional Oil and Gas industry has seen growth over the last ten years that has drastically transformed the domestic energy outlook while bringing up increased concerns over climate and environmental issues. ... The Unconventional Oil and Gas industry has seen growth over the last ten years that has drastically transformed the domestic energy outlook while bringing up increased concerns over climate and environmental issues. The rise of ESG and RSG can be seen as direct answers to these growing issues as communities and operators have both begun to demand better practices to limit the overall effects of UOG production. Few quantifiable metrics exist that holistically try to determine the overall effect UOG production has on local water resources. The FR2 metric/framework developed in this paper attempts to use commonly kept data such as water withdrawn and flowback volumes in conjunction with a new water stress index to quantify the effects operators are having on local water supplies. Testing this framework on a handful of operators from the Marcellus basin using open-source data revealed the value added by these methods as well as their use in a general RSG program. 展开更多
关键词 Responsible sourced Gas UOG Water Stewardship Water Stress Water Sustainability
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Updating Traditional 1/50,000 Topographic Maps Using Crowd-Sourced Geodata and Free Sources Satellite Images
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作者 Atef Belhaj Ali Mohamed Hafedh Hamza 《Journal of Geographic Information System》 2021年第2期274-286,共13页
This paper addresses how open geodata and crowd-sourced geodata, and the open geoportals might be integrated with the mainstream surveying and mapping practices to update traditional topomaps quickly and inexpensively... This paper addresses how open geodata and crowd-sourced geodata, and the open geoportals might be integrated with the mainstream surveying and mapping practices to update traditional topomaps quickly and inexpensively, that might be otherwise impossible to do it due to economic and logistic situations. The abundant geographic data on the internet could be used to update topographic maps while avoiding the time-consuming nature of the traditional method. To be able to use them, it is necessary to measure and quantify the quality of these data, as well as to verify their credibility, in order to incorporate them into official topographic maps. The proposed approach takes advantage of neocartography, and it’s not about further developing a new approaches, but looking differently at how data is collected, assembled controlled and been used for updating topomaps. At the beginning, the methodology used about how open geodata and crowd-sourced geodata involved in collecting, simplifying, generalizing, controlling and generating useful cartographic information that complement traditional and conventional counterparts is presented. This methodology was applied on a 1/50,000 topomap located in the north of Jeddah city (western region of Saudi Arabia), and we have demonstrated that by using this type of data, it is possible to update topographic maps quickly and at a lower cost while maintaining cartographic precision and accuracy standards. 展开更多
关键词 Topomaps Map Update Open Geodata Crowed sourced Geodata Open Street Map (OSM) Geodata Quality Hausdorff Distance
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R&D and application of voltage sourced converter based high voltage direct current engineering technology in China 被引量:58
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作者 Guangfu TANG Zhiyuan HE Hui PANG 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2014年第1期1-15,共15页
As a new generation of direct current(DC)transmission technology,voltage sourced converter(VSC)based high voltage direct current(HVDC)has been widely developed and applied all over the world.China has also carried out... As a new generation of direct current(DC)transmission technology,voltage sourced converter(VSC)based high voltage direct current(HVDC)has been widely developed and applied all over the world.China has also carried out a deep technical research and engineering application in this area,and at present,it has been stepped into a fast growing period.This paper gives a general review over China’s VSC based HVDC in terms of engineering technology,application and future development.It comprehensively analyzes the technical difficulties and future development orientation on the aspects of the main configurations of VSC based HVDC system,topological structures of converters,control and protection technologies,flexible DC cables,converter valve tests,etc.It introduces the applicable fields and current status of China’s VSC based HVDC projects,and analyzes the application trends of VSC based HVDC projects both in China and all over the world according to the development characteristics and demands of future power grids. 展开更多
关键词 Voltage sourced converter based high voltage direct current(VSC based HVDC) Two-level converter Modular multi-level converter(MMC) Direct current grid(DC grid)
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Characteristics of Submicron Aerosols (PM_(1)) in a Yangtze River Delta Megacity:Composition,Sources,and Light Absorption
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作者 Shiyue YANG Haifeng MENG +8 位作者 Ning ZHANG Shijie CUI Yuanjie SHAN Yu HUANG Yunlong XU Chongchong ZHANG Xinlei GE Mindong CHEN Junfeng WANG 《Advances in Atmospheric Sciences》 2026年第1期247-258,共12页
We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),org... We conducted a field campaign to investigate the chemical composition,sources,and light absorption of submicron aerosols(PM_(1))from early 2022 in Nanjing,China.The average concentration of PM_(1) was 31μg m^(−3),organics(33%)constituted the largest fraction,followed by nitrate(30%),sulfate(18%),ammonium(15%),chloride(3%),and rBC(2%).Four organic aerosol(OA)subcomponents were identified,including two primary OA(POA)and two secondary OA(SOA).The less-oxidized SOA(LO-OOA)contributes the most to the total OA mass(59%).LO-OOA is tightly correlated with the tracer ion C_(2)H_(4)O_(2)^(+)from levoglucosan,and another aged biomass-burning derived species,K_(3)SO_(4)^(+),suggesting it was likely influenced by aged biomass-burning OA.Our study also revealed that fireworks during the Spring Festival have a detrimental impact on air quality,contributing to secondary formation and accumulation under static winter meteorological conditions,prolonging the pollution duration.Also,LO-OOA was found to have the strongest light-absorbing ability.Our results highlight that the light absorption of LO-OOA can mainly be attributed to the C_(x)H_(y)N^(+) family,increased with the double-bond equivalent value.The more-oxidized SOA(MO-OOA)exhibited a negligible light absorption and was strongly correlated with daytime photochemical processes,implying a light-bleaching effect.This study enhances our understanding of the regional contribution of biomass combustion and fireworks to PM_(1) pollution in Nanjing,a typical megacity in the Yangtze River Delta region,during winter,aiding in the development of strategies for long-term air quality improvement in the region. 展开更多
关键词 PM_(1) source apportionment Yangtze River Delta Region brown carbon
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Source process of the 2021 M_(W)6.6 outer rise earthquake off the west coast of northern Sumatra
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作者 Bagus Adi Wibowo Hongru Li +5 位作者 Anisa Nurbaeti Rahayu Ling Bai Supriyanto Rohadi Putu Hendra Widyadharma Abraham Arimuko Suko Prayitno Adi 《地球与行星物理论评(中英文)》 2026年第1期51-61,共11页
The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer r... The complexity of the seismicity pattern for the subduction zone along the oceanic plate triggered the outer rise events and revealed cyclic tectonic deformation conditions along the plate subduction zones.The outer rise earthquakes have been observed along the Sunda arc,following the estimated rupture area of the 2005 M_(W)8.6 Nias earthquakes.Here,we used kinematic waveform inversion(KIWI)to obtain the source parameters of the 14 May 2021 M_(W)6.6 event off the west coast of northern Sumatra and to define the fault plane that triggered this outer rise event.The KIWI algorithm allows two types of seismic source to be configured:the moment tensor model to describe the type of shear with six moment tensor components and the Eikonal model for the rupture of pure double-couple sources.This method was chosen for its flexibility to be applied for different sources of seismicity and also for the automated full-moment tensor solution with real-time monitoring.We used full waveform traces from 8 broadband seismic stations within 1000 km epicentral distances sourced from the Incorporated Research Institutions for Seismology(IRIS-IDA)and Geofon GFZ seismic record databases.The initial origin time and hypocenter values are obtained from the IRIS-IDA.The synthetic seismograms used in the inversion process are based on the existing regional green function database model and were accessed from the KIWI Tools Green's Function Database.The obtained scalar seismic moment value is 1.18×10^(19)N·m,equivalent to a moment magnitude M_(W)6.6.The source parameters are 140°,44°,and−99°for the strike,dip,and rake values at a centroid depth of 10.2 km,indicating that this event is a normal fault earthquake that occurred in the outer rise area.The outer rise events with normal faults typically occur at the shallow part of the plate,with nodal-plane dips predominantly in the range of 30°-60°on the weak oceanic lithosphere due to hydrothermal alteration.The stress regime around the plate subduction zone varies both temporally and spatially due to the cyclic influences of megathrust earthquakes.Tensional outer rise earthquakes tend to occur after the megathrust events.The relative timing of these events is not known due to the viscous relaxation of the down going slab and poroelastic response in the trench slope region.The occurrence of the 14 May 2021 earthquake shows the seismicity in the outer rise region in the strongly coupled Sunda arc subduction zone due to elastic bending stress within the duration of the seismic cycle. 展开更多
关键词 outer rise earthquake kinematic waveform inversion source process
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Advancing Asian Monsoon Climate Prediction under Global Change:Progress,Challenges,and Outlook
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作者 Bin WANG Fei LIU +9 位作者 Renguang WU Qinghua DING Shaobo QIAO Juan LI Zhiwei WU Keerthi SASIKUMAR Jianping LI Qing BAO Haishan CHEN Yuhang XIANG 《Advances in Atmospheric Sciences》 2026年第1期1-29,共29页
Predicting monsoon climate is one of the major endeavors in climate science and is becoming increasingly challenging due to global warming. The accuracy of monsoon seasonal predictions significantly impacts the lives ... Predicting monsoon climate is one of the major endeavors in climate science and is becoming increasingly challenging due to global warming. The accuracy of monsoon seasonal predictions significantly impacts the lives of billions who depend on or are affected by monsoons, as it is essential for the water cycle, food security, ecology, disaster prevention, and the economy of monsoon regions. Given the extensive literature on Asian monsoon climate prediction, we limit our focus to reviewing the seasonal prediction and predictability of the Asian Summer Monsoon (ASM). However, much of this review is also relevant to monsoon predictions in other seasons and regions. Over the past two decades, considerable progress has been made in the seasonal forecasting of the ASM, driven by an enhanced understanding of the sources of predictability and the dynamics of seasonal variability, along with advanced development in sophisticated models and technologies. This review centers on advances in understanding the physical foundation for monsoon climate prediction (section 2), significant findings and insights into the primary and regional sources of predictability arising from feedback processes among various climate components (sections 3 and 4), the effects of global warming and external forcings on predictability (section 5), developments in seasonal prediction models and techniques (section 6), the challenges and limitations of monsoon climate prediction (section 7), and emerging research trends with suggestions for future directions (section 8). We hope this review will stimulate creative activities to enhance monsoon climate prediction. 展开更多
关键词 Asian summer monsoon monsoon climate prediction climate predictability predictability sources seasonal prediction models seasonal prediction techniques artificial intelligence
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Interleukin-17 family in health and immune diseases:From origin to clinical implications
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作者 Guozhen Deng Mengdi Guo +3 位作者 Jiahui Fan Weiyan Wang Mei-Ling Jiang Cun-Jin Zhang 《Neural Regeneration Research》 2026年第5期1809-1833,共25页
The interleukin-17 family is the key group of cytokines and displays a broad spectrum of biological functions,including regulating the inflammatory cascade in various autoimmune and inflammatory diseases,such as multi... The interleukin-17 family is the key group of cytokines and displays a broad spectrum of biological functions,including regulating the inflammatory cascade in various autoimmune and inflammatory diseases,such as multiple sclerosis,neuromyelitis optica spectrum disorder,myasthenia gravis,Guillain–Barre syndrome,acute disseminated encephalomyelitis,diabetes,inflammatory skin diseases,joint inflammation,and cancer.Although the function of the interleukin-17 family has attracted increasing research attention over many years,the expression,function,and regulation mechanisms of different interleukin-17 members are complicated and still only partially understood.Currently,the interleukin-17A pathway is considered a critical therapeutic target for numerous immune and chronic inflammatory diseases,with several monoclonal antibodies against interleukin-17A having been successfully used in clinical practice.Whether other interleukin-17 members have the potential to be targeted in other diseases is still debated.This review first summarizes the recent advancements in understanding the physicochemical properties,physiological functions,cellular origins,and downstream signaling pathways of different members and corresponding receptors of the interleukin-17 family.Subsequently,the function of interleukin-17 in various immune diseases is discussed,and the important role of interleukin-17 in the pathological process of immune diseases is demonstrated from multiple perspectives.Then,the current status of targeted interleukin-17 therapy is summarized,and the effectiveness and safety of targeted interleukin-17 therapy are analyzed.Finally,the clinical application prospects of targeting the interleukin-17 pathway are discussed. 展开更多
关键词 antibody therapy autoimmune disease cellular source clinical applications INTERLEUKIN-17 interleukin-17 receptor inflammatory diseases physiological responses signaling pathway therapeutic strategy
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Analytics of big geosocial media and crowdsourced data 被引量:1
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作者 Songnian Li Monica Wachowicz Hongchao Fan 《Big Earth Data》 EI 2021年第1期1-4,共4页
Numerous crowdsourcing and social media platforms such as CrowdSpring,Idea Bounty,DesignCrowd,Facebook,Twitter,Flickr,Weibo,WeChat,and Instagram are creating and sharing vast amounts of user-generated content that can... Numerous crowdsourcing and social media platforms such as CrowdSpring,Idea Bounty,DesignCrowd,Facebook,Twitter,Flickr,Weibo,WeChat,and Instagram are creating and sharing vast amounts of user-generated content that can reveal timely and useful infor-mation for detecting traffic patterns,mitigating security risks and other types of time-critical events,discovering social structures characteristics,predicting human movement,etc.Crowdsourcing,also known as volunteered geographic information(VGI),has added a new dimension to traditional geospatial data acquisition by providing fine-grained proxy data for human activity research in urban studies(Chen et al.,2016;Niu&Silva,2020).However,analyzing big geosocial media and crowdsourced data brings significant methodological and theoretical challenges due to the uncertain user representability when referring to human behavior in general,the inherent noisy data that requires high-performance cost of preprocessing,and the heterogeneity in quality and quantity of sources.In particular,geosocial media data and their derived metrics can provide valuable insights and policy strategies,but they require a deep understanding of what the metrics actually measure(Zook,2017).All of these underpin complex assessments,not mention-ing the ethnic and privacy issues.Therefore,new sets of methods and tools are required to analyze the big data from crowdsourcing and social media platforms. 展开更多
关键词 SOURCE MEDIA COVERING
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基于多种概念性模型的高寒流域径流模拟
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作者 高诺 尹冬勤 +3 位作者 李想 黄静 黄跃飞 魏加华 《应用基础与工程科学学报》 北大核心 2025年第5期1310-1322,共13页
开展流域水文模拟研究,揭示径流历史规律和预估未来趋势,对于合理开发和利用流域水资源具有重要指导意义.以青藏高原东北部的大通河流域为研究区,利用eWater Source平台搭载的6种概念性水文模型,以CMFD和ERA5-Land气象数据驱动开展两次... 开展流域水文模拟研究,揭示径流历史规律和预估未来趋势,对于合理开发和利用流域水资源具有重要指导意义.以青藏高原东北部的大通河流域为研究区,利用eWater Source平台搭载的6种概念性水文模型,以CMFD和ERA5-Land气象数据驱动开展两次日尺度径流模拟实验评估:(1)单一模型应用于全流域实验;(2)考虑冰雪因素的多模型组合实验.此外,在每次实验中考虑以子流域为单位率定参数集,对比分析了不同实验设置对结果的影响.单一模型实验结果表明:GR4J、AWBM、Sacramento、SIMHYD、IHACRES-CMD和GR4JSG模型在流域出口享堂站率定期纳什效率系数(NSE)分别为0.73、0.74、0.71、0.62、0.75和0.80.实验筛选出的IHACRES-CMD与GR4JSG组合模型率定期在享堂站NSE为0.83,青石嘴站NSE为0.75,相较于单一模型,组合模型的结果进一步优化,且与同区域其他分布式模型的研究结果基本相当,为研究推荐方法. 展开更多
关键词 径流模拟 eWater Source 概念性水文模型 大通河 高寒流域
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基于16S rRNA基因测序和Source Tracker模型分析生驼乳安全风险关键点
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作者 薛宇飞 冀承昊 +1 位作者 何静 吉日木图 《食品与发酵工业》 北大核心 2025年第23期235-243,共9页
驼乳是人类各类营养元素摄入的良好来源之一,富含的营养价值更易被吸收利用,对人体健康、疾病预防及治疗具有重要作用。但由于驼乳受到不卫生的环境条件、生产过程不规范或处理方法不当等影响,极易遭受微生物的污染,这不仅威胁到驼乳产... 驼乳是人类各类营养元素摄入的良好来源之一,富含的营养价值更易被吸收利用,对人体健康、疾病预防及治疗具有重要作用。但由于驼乳受到不卫生的环境条件、生产过程不规范或处理方法不当等影响,极易遭受微生物的污染,这不仅威胁到驼乳产品的品质与安全,也成为了制约驼乳产业持续健康发展的关键因素之一。因此,该研究通过16S rRNA扩增子测序技术对挤奶瓶、乳头夹、储奶罐、乳头、饮用水、饲料、粪便和驼舍空气样品中微生物多样性比较分析。采用Source Tracker分析模型对3个牧场中的微生物风险关键点分析。研究表明,A驼场生乳中乳球菌和金黄杆菌在属水平上的相对丰度较高,占比分别为52.37%和15.76%;而在B驼场生乳在属水平上主要优势菌属为罗思氏菌,相对丰度占比高达83.64%;C驼场生乳微生物属占比较高的为罗思氏菌和不动杆菌,分别为64.85%和17.58%。利用Source Tracker模型对A、B和C三个驼场的挤奶瓶、乳头夹、储奶罐、乳头、饮用水、饲料、粪便和驼舍空气样品8个风险关键点进行分析,确定造成原料乳微生物污染的风险关键点为乳头、乳头夹、挤奶瓶和储奶罐。该研究结果可为生驼乳安全性的提高提供参考依据。 展开更多
关键词 生驼乳 微生物风险分析 关键点控制 16S rRNA测序 Source Tracker模型
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Research progress on the environmental risk assessment and remediation technologies of heavy metal pollution in agricultural soil 被引量:9
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作者 Xurui Mai Jing Tang +6 位作者 Juexuan Tang Xinyue Zhu Zhenhao Yang Xi Liu Xiaojie Zhuang Guang Feng Lin Tang 《Journal of Environmental Sciences》 2025年第3期1-20,共20页
Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remedi... Controlling heavy metal pollution in agricultural soil has been a significant challenge.These heavy metals seriously threaten the surrounding ecological environment and human health.The effective assessment and remediation of heavy metals in agricultural soils are crucial.These two aspects support each other,forming a close and complete decisionmaking chain.Therefore,this review systematically summarizes the distribution characteristics of soil heavy metal pollution,the correlation between soil and crop heavy metal contents,the presence pattern and migration and transformation mode of heavy metals in the soil-crop system.The advantages and disadvantages of the risk evaluation tools and models of heavy metal pollution in farmland are further outlined,which provides important guidance for an in-depth understanding of the characteristics of heavymetal pollution in farmland soils and the assessment of the environmental risk.Soil remediation strategies involve multiple physical,chemical,biological and even combined technologies,and this paper compares the potential and effect of the above current remediation technologies in heavy metal polluted farmland soils.Finally,the main problems and possible research directions of future heavy metal risk assessment and remediation technologies in agricultural soils are prospected.This review provides new ideas for effective assessment and selection of remediation technologies based on the characterization of soil heavy metals. 展开更多
关键词 Source Migration transformation Risk assessment REMEDIATION Heavy metals Agricultural soils
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Rainfall impacts on nonpoint nitrogen and phosphorus dynamics in an agricultural river in subtropical montane reservoir region of southeast China 被引量:4
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作者 Yuanyi Wang Hai Xu +9 位作者 Xingchen Zhao Lijuan Kang Yu Qiu Hans Paerl Guangwei Zhu Huiyun Li Mengyuan Zhu Boqiang Qin Yunlin Zhang Mingliang Liu 《Journal of Environmental Sciences》 2025年第3期551-563,共13页
The increased frequency and intensity of heavy rainfall events due to climate change could potentially influence the movement of nutrients from land-based regions into recipient rivers.However,little information is av... The increased frequency and intensity of heavy rainfall events due to climate change could potentially influence the movement of nutrients from land-based regions into recipient rivers.However,little information is available on how the rainfall affect nutrient dynamics in subtropicalmontane rivers with complex land use.This study conducted high-frequency monitoring to study the effects of rainfall on nutrients dynamics in an agricultural river draining to Lake Qiandaohu,a montane reservoir of southeast China.The results showed that riverine total nitrogen(TN)and total phosphorus(TP)concentrations increased continuously with increasing rainfall intensity,while TN:TP decreased.The heavy rainfall and rainstorm drove more than 30%of the annual N and P loading in only 5.20%of the total rainfall period,indicating that increased storm runoff is likely to exacerbate eutrophication in montane reservoirs.NO_(3)^(−)-N is the primary nitrogen form lost,while particulate phosphorus(PP)dominated phosphorus loss.Themain source of N is cropland,and themain source of P is residential area.Spatially,forestedwatersheds have better drainage quality,while it is still a potential source of nonpoint pollution during rainfall events.TN and TP concentrations were significantly higher at sites dominated by cropland and residential area,indicating their substantial contributions to deteriorating river water quality.Temporally,TN and TP concentrations reached high values in May-August when rainfall was most intense,while they were lower in autumn and winter than that in spring and summer under the same rainfall intensities.The results emphasize the influence of rainfall-runoff and land use on dynamics of riverine N and P loads,providing guidance for nutrient load reduction planning for Lake Qiandaohu. 展开更多
关键词 Non-point source pollution Rainfall events Land use type Mountain area Deepwater reservoir
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Separate Source Channel Coding Is Still What You Need:An LLM-Based Rethinking 被引量:3
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作者 REN Tianqi LI Rongpeng +5 位作者 ZHAO Mingmin CHEN Xianfu LIU Guangyi YANG Yang ZHAO Zhifeng ZHANG Honggang 《ZTE Communications》 2025年第1期30-44,共15页
Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information ... Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information semantics.Nevertheless,this paper challenges the conventional JSCC paradigm and advocates for adopting separate source channel coding(SSCC)to enjoy a more underlying degree of freedom for optimization.We demonstrate that SSCC,after leveraging the strengths of the Large Language Model(LLM)for source coding and Error Correction Code Transformer(ECCT)complemented for channel coding,offers superior performance over JSCC.Our proposed framework also effectively highlights the compatibility challenges between Sem Com approaches and digital communication systems,particularly concerning the resource costs associated with the transmission of high-precision floating point numbers.Through comprehensive evaluations,we establish that assisted by LLM-based compression and ECCT-enhanced error correction,SSCC remains a viable and effective solution for modern communication systems.In other words,separate source channel coding is still what we need. 展开更多
关键词 separate source channel coding(SSCC) joint source channel coding(JSCC) end-to-end communication system Large Language Model(LLM) lossless text compression Error Correction Code Transformer(ECCT)
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Source Characteristics and Induced Hazards of the 2025 M6.8 Dingri Earthquake,Xizang,China,Revealed by Imaging Geodesy 被引量:2
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作者 Chen Yu Zhenhong Li +11 位作者 Xiaoning Hu Chuang Song Suju Li Haihui Liu Jie Li Bingquan Han Zhenjiang Liu Ming Liu Shuang Zhu Xiaoye Hao Zhiyuan Li Jianbing Peng 《Journal of Earth Science》 2025年第2期847-851,共5页
0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,... 0 INTRODUCTION.According to the China Earthquake Networks Center,an M6.8 earthquake struck Dingri County,Xizang Autonomous Region,China,on 7 January 2025 at 9:05 a.m.local time.The epicenter is located at 28.5°N,87.45°E,with a depth of~10 km. 展开更多
关键词 source characteristics M earthquake Xizang imaging geodesy induced hazards Dingri China
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Occurrence of phthalate esters in the yellow and Yangtze rivers of china:Risk assessment and source apportionment 被引量:2
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作者 Qinkui Miao Wenxiang Ji +1 位作者 Huiyu Dong Ying Zhang 《Journal of Environmental Sciences》 2025年第3期628-637,共10页
Phthalate esters(PAEs),recognized as endocrine disruptors,are released into the environment during usage,thereby exerting adverse ecological effects.This study investigates the occurrence,sources,and risk assessment o... Phthalate esters(PAEs),recognized as endocrine disruptors,are released into the environment during usage,thereby exerting adverse ecological effects.This study investigates the occurrence,sources,and risk assessment of PAEs in surface water obtained from 36 sampling points within the Yellow River and Yangtze River basins.The total concentration of PAEs in the Yellow River spans from124.5 to 836.5 ng/L,with Dimethyl phthalate(DMP)(75.4±102.7 ng/L)and Diisobutyl phthalate(DiBP)(263.4±103.1 ng/L)emerging as the predominant types.Concentrations exhibit a pattern of upstream(512.9±202.1 ng/L)>midstream(344.5±135.3 ng/L)>downstream(177.8±46.7 ng/L).In the Yangtze River,the total concentration ranges from 81.9 to 441.6 ng/L,with DMP(46.1±23.4 ng/L),Diethyl phthalate(DEP)(93.3±45.2 ng/L),and DiBP(174.2±67.6 ng/L)as the primary components.Concentration levels follow a midstream(324.8±107.3 ng/L)>upstream(200.8±51.8 ng/L)>downstream(165.8±71.6 ng/L)pattern.Attention should be directed towards the moderate ecological risks of DiBP in the upstream of HH,and both the upstream and midstream of CJ need consideration for the moderate ecological risks associated with Di-n-octyl phthalate(DNOP).Conversely,in other regions,the associated risk with PAEs is either low or negligible.The main source of PAEs in Yellow River is attributed to the release of construction land,while in the Yangtze River Basin,it stems from the accumulation of pollutants in lakes and forests discharged into the river.These findings are instrumental for pinpointing sources of PAEs pollution and formulating control strategies in the Yellow and Yangtze Rivers,providing valuable insights for global PAEs research in other major rivers. 展开更多
关键词 PHTHALATES Spatial variation Potential sources Risk assessment
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Sources and types of collagens used in the cosmetic industry 被引量:2
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作者 Mingjie Tong Xiaona Zhang +2 位作者 Jiongni Zhong Qiuling Xie Sheng Xiong 《Journal of Dermatologic Science and Cosmetic Technology》 2025年第1期64-72,共9页
Collagen is a class of mammalian extracellular matrix of the main structural proteins,widely present in the skin,bone,muscle and other tissues and it plays a role in supporting,repairing,and protecting tissue cells.Na... Collagen is a class of mammalian extracellular matrix of the main structural proteins,widely present in the skin,bone,muscle and other tissues and it plays a role in supporting,repairing,and protecting tissue cells.Natural source extraction and artificial synthesis provide a rich source of collagen.As a macromolecular material,collagen has good application potential in cosmetics,pharmaceutical,medical and food industries.Collagen has generated a great deal of interest in the cosmetic industry due to its abundance,strength,and direct correlation with skin aging.Collagen is widely used in cosmetics due to its unique structure,good biocompatibility and low antigenicity,as well as rich biological functions.To enhance the youthfulness and health of the user,the cosmetic industry adds collagen to products such as eye creams,face creams,and nutritional supplements,and uses it in medical aesthetic techniques such as tissue fillers,skin replacement,and soft skin enhancement.This paper mainly reviews the sources and types of collagen used in cosmetics industry,then introduces the effects of collagen in cosmetics and prospects the development prospects of collagen in dermatologic and cosmetic fields. 展开更多
关键词 Collagen Sources and types Cosmetic industry COSMETICS
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Tip-enhanced Raman scattering of glucose molecules 被引量:3
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作者 Zhonglin Xie Chao Meng +3 位作者 Donghua Yue Lei Xu Ting Mei Wending Zhang 《Opto-Electronic Science》 2025年第5期2-9,共8页
Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtain... Glucose molecules are of great significance being one of the most important molecules in metabolic chain.However,due to the small Raman scattering cross-section and weak/non-adsorption on bare metals,accurately obtaining their"fingerprint information"remains a huge obstacle.Herein,we developed a tip-enhanced Raman scattering(TERS)technique to address this challenge.Adopting an optical fiber radial vector mode internally illuminates the plasmonic fiber tip to effectively suppress the background noise while generating a strong electric-field enhanced tip hotspot.Furthermore,the tip hotspot approaching the glucose molecules was manipulated via the shear-force feedback to provide more freedom for selecting substrates.Consequently,our TERS technique achieves the visualization of all Raman modes of glucose molecules within spectral window of 400-3200 cm^(-1),which is not achievable through the far-field/surface-enhanced Raman,or the existing TERS techniques.Our TERS technique offers a powerful tool for accurately identifying Raman scattering of molecules,paving the way for biomolecular analysis. 展开更多
关键词 tip-enhanced Raman scattering scanning near-field optical microscope fiber vector light field tip nanofocusing light source
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Occurrence and potential risks of organophosphate esters in agricultural soils:A case study of Fuzhou City,Southeast China 被引量:2
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作者 Tao Wang Hong Zhang +6 位作者 Chong Huang Yujie Ben Hanlin Zhou Hangting Guo Yonghe Han Yong Zhang Ping Tong 《Journal of Environmental Sciences》 2025年第4期571-581,共11页
Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(... Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(ΣOPEs)in soil ranged from 1.33 to 96.5 ng/g dry weight(dw),with an average value of 17.1 ng/g dw.Especially,halogenated-OPEs were the predominant group with amean level of 9.75 ng/g dw,and tris(1-chloro-2-propyl)phosphate(TCIPP)was the most abundant OPEs,accounting for 51.1%ofΣOPEs.The concentrations of TCIPP andΣOPEs were found to be significantly higher(P<0.05)in soils of urban areas than those in suburban areas.In addition,the use of agricultural plastic films and total organic carbon had a positive effect on the occurrence of OPE in this study.The positive matrix factorization model suggested complex sources of OPEs in agricultural soils from Fuzhou.The ecological risk assessment demonstrated that tricresyl phosphate presented a medium risk to land-based organisms(0.1≤risk quotient<1.0).Nevertheless,the carcinogenic and noncarcinogenic risks for human exposure to OPEs through soil ingestion and dermal absorption were negligible.These findings would facilitate further investigations into the pollution management and risk control of OPEs. 展开更多
关键词 Organophosphate esters(OPEs) Agricultural soils Spatial distribution Source identification Risk assessment
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Characterization and source apportionment of volatile organic compounds in Hong Kong:A 5-year study for three different archetypical sites 被引量:2
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作者 Yuchen Mai Vincent Cheung +5 位作者 Peter K.K.Louie Kenneth Leung Jimmy C.H.Fung Alexis K.H.Lau Donald R.B.lake Dasa Gu 《Journal of Environmental Sciences》 2025年第5期424-440,共17页
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ... Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas. 展开更多
关键词 Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation
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