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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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Facilitating ultra-fast lithium ion diffusion in face-centered cubic oxides via over-stoichiometric face-sharing configurations
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作者 Xiaohan Zhang Bo Xiao 《Chinese Journal of Structural Chemistry》 2025年第2期3-4,共2页
As an important sustainable energy source,Li-ion batteries have been widely used in mobile phones,electric vehicles,large-scale energy storage and aerospace.However,due to the inevitable safety risks of traditional li... As an important sustainable energy source,Li-ion batteries have been widely used in mobile phones,electric vehicles,large-scale energy storage and aerospace.However,due to the inevitable safety risks of traditional liquid Li-ion batteries,the use of all-solid-state batteries to replace organic liquid electrolytes has become one of the most effective ways to solve safety problem.Solid-state electrolyte(SSE)is the core part of allsolid-state Li-ion battery,and ideal SSE has the characteristics of high ionic conductivity,wide enough electrochemical stability window,suitable mechanical strength and excellent chemical stability,the first among which is particularly an essential prerequisite.While,so far only a few SSEs exhibit the Li ionic conductivities higher than 10^(-4) S/cm at room temperature. 展开更多
关键词 ultra fast lithium ion diffusion safety risks safety problemsolid state stoichiometric face sharing configurations all solid state batteries organic liquid electrolytes sustainable energy sourceli ion face centered cubic oxides
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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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Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain 被引量:2
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作者 Xiao Zhang Junfeng Wang +8 位作者 Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue Zhang Miaomiao Zhang Shuangying Ni Eleonora Aruffo 《Journal of Environmental Sciences》 2025年第3期465-475,共11页
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe... VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels. 展开更多
关键词 Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment
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Restoration of hydrocarbon generation potential of the highly mature Lower Cambrian Yuertusi Formation source rocks in the Tarim Basin 被引量:2
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作者 Yao Hu Cheng-Zao Jia +6 位作者 Jun-Qing Chen Xiong-Qi Pang Lin Jiang Chen-Xi Wang Hui-Yi Xiao Cai-Jun Li Yu-Jie Jin 《Petroleum Science》 2025年第2期588-606,共19页
The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Pa... The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Paleozoic.However,its hydrocarbon generation and evolution characteristics and resource potential have long been constrained by deeply buried strata and previous research.In this paper,based on the newly obtained ultra-deep well drilling data,the hydrocarbon generation and expulsion model ofЄ_(1)y shale was established by using data-driven Monte Carlo simulation,upon which the hydrocarbon generation,expulsion,and retention amounts were calculated by using the diagenetic method.The research indicates that theЄ_(1)y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×10^(10)t,the cumulative hydrocarbon expulsion is 35.59×10^(10)t,and the cumulative residual hydrocarbon is 33.29×10^(10)t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ_(1)y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ_(1)y is the most significant source rock contributing to the marine oil and gas resources in the Tarim Basin,filling the gap in hydrocarbon expulsion calculation in the study area,and providing an important basis for the formation and distribution of Paleozoic hydrocarbon reservoirs.The prospect of deep ultra-deep oil and gas exploration in the Tarim Basin is promising.Especially,the large area of dolomite reservoirs under the Cambrian salt and source rock interiors are the key breakthrough targets for the next exploration in the Tarim Basin. 展开更多
关键词 Evaluation of resource potential Highly mature hydrocarbon source rocks Yuertusi formation Tarim Basin
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Enhanced VOC emission with increased temperature contributes to the shift of O_(3)-precursors relationship and optimal control strategy 被引量:2
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作者 Fangqi Qu Yuanjie Huang +11 位作者 Yemin Shen Genqiang Zhong Yan Xu Lingling Jin Hongtao Qian Chun Xiong Fei Zhang Jiasi Shen Bingye Xu Xudong Tian Zhengning Xu Zhibin Wang 《Journal of Environmental Sciences》 2025年第4期218-229,共12页
Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution control.Continuousmeasurement of O_(3)and the major precurs... Assessing the impact of anthropogenic volatile organic compounds(VOCs)on ozone(O_(3))formation is vital for themanagement of emission reduction and pollution control.Continuousmeasurement of O_(3)and the major precursorswas conducted in a typical light industrial city in the YRD region from 1 May to 25 July in 2021.Alkanes were the most abundant VOC group,contributing to 55.0%of TVOCs concentration(56.43±21.10 ppb).OVOCs,aromatics,halides,alkenes,and alkynes contributed 18.7%,9.6%,9.3%,5.2%and 1.9%,respectively.The observational site shifted from a typical VOC control regime to a mixed regime from May to July,which can be explained by the significant increase of RO_(x)production,resulting in the transition of environment from NOx saturation to radical saturation with respect to O_(3)production.The optimal O_(3)control strategy should be dynamically changed depending on the transition of control regime.Under NOx saturation condition,minimizing the proportion of NOx in reduction could lead to better achievement of O_(3)alleviation.Under mixed control regime,the cut percentage gets the top priority for the effectiveness of O_(3)control.Five VOCs sources were identified:temperature dependent source(28.1%),vehicular exhausts(19.9%),petrochemical industries(7.2%),solvent&gasoline usage(32.3%)and manufacturing industries(12.6%).The increase of temperature and radiation would enhance the evaporation related VOC emissions,resulting in the increase of VOC concentration and the change of RO_(x)circulation.Our results highlight determination of the optimal control strategies for O_(3)pollution in a typical YRD industrial city. 展开更多
关键词 O_(3)pollution Volatile organic compounds Photochemical box model Source apportionment Optimal O_(3)control strategies
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Development of a coupled model to simulate and assess arsenic contamination and impact factors in the Jinsha River Basin,China 被引量:1
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作者 Yidian Sun Xu Zhang +5 位作者 Hong Peng Wenting Zhou Anna Jiang Feng Zhou Hao Wang Wanshun Zhang 《Journal of Environmental Sciences》 2025年第1期50-61,共12页
With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the pr... With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control strategies.Taking the industrialintensive Jinsha River Basin as typical area,a two-dimensional hydrodynamic water quality model coupled with Soil andWater Assessment Tool(SWAT)model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal resolution.The effects of hydro-climate change,hydropower station construction and non-point source emissions on Aswere quantified based on the coupled model.The result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to downstream.Due to the enhanced rainfall,the As concentration was significantly higher during the rainy season than the dry season.Hydro-climate change and the construction of hydropower station not only affected the dissolved As concentration,but also affected the adsorption and desorption of As in sediment.Furthermore,As concentration increased with the input of non-point source pollution,with the maximum increase about 30%,resulting that non-point sources contributed important pollutant impacts to waterways.The coupled model used in pollutant behavior analysis is generalwith high potential application to predict and mitigate water pollution. 展开更多
关键词 Watershed system ARSENIC Modeling DISTRIBUTION Hydro-climate change Non-point source pollution
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