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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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Redundant source-wavelet amplitude influence in wave-equation migration/demigration flow and its removal
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作者 QianCheng Liu JiaLe Kang Jie Li 《Earth and Planetary Physics》 2026年第1期75-81,共7页
In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly... In wave-equation migration and demigration,the cross-correlation imaging/forwarding step implicitly injects an additional copy of the source wavelet,so that the amplitude spectrum of the wavelet is applied redundantly(effectively imposing a wavelet-spectrum weighting,often akin to an amplitude-squared bias).This redundancy degrades structural fidelity and amplitude balance yet is frequently overlooked.We(i)formalize the mechanism by which cross-correlation duplicates the source-wavelet amplitude effect in both migration and demigration,and(ii)introduce a source-equalized operator that removes the redundancy by deconvolving(or dividing by)the wavelet amplitude spectrum in the imaging condition and its demigration counterpart,while leaving phase/kinematics intact.Using a band-limited Ricker wavelet on a two-layer model and on Marmousi,we show that,if unmanaged,the redundant wavelet spectrum broadens main lobes,introduces ringing,and suppresses vertical resolution in migrated images,and inflates spectrum mismatches between demigrated and observed data even when peak times agree.With our correction,images recover observed-data-consistent bandwidth and sharpened interfaces,and demigrated data also exhibit improved spectrum conformity and reduced amplitude misfit.The results clarify when source amplitudes matter,why cross-correlation makes them redundantly matter,and how a lightweight spectral correction restores physically meaningful amplitude behavior in wave-equation migration/demigration. 展开更多
关键词 wave-equation migration DEMIGRATION cross-correlation imaging condition source wavelet amplitude spectrum spectral deconvolution
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Preparation and measurement of an^(37)Ar source for liquid xenon detector calibration
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作者 Xu‑Nan Guo Chang Cai +8 位作者 Fei Gao Yang Lei Kai‑Hang Li Chun‑Lei Su Ze‑Peng Wu Xiang Xiao Ling‑Feng Xie Yi‑Fei Zhao Xiao‑Peng Zhou 《Nuclear Science and Techniques》 2026年第1期202-211,共10页
We present the preparation and measurement of the radioactive isotope^(37)Ar,which was produced using thermal neutrons from a reactor,as a calibration source for liquid xenon time projection chambers.^(37)Ar is a low-... We present the preparation and measurement of the radioactive isotope^(37)Ar,which was produced using thermal neutrons from a reactor,as a calibration source for liquid xenon time projection chambers.^(37)Ar is a low-energy calibration source with a half-life of 35.01 days,making it suitable for calibration in the low-energy region of liquid xenon dark-matter experiments.Radioactive isotope^(37)Ar was produced by irradiating ^(36)Ar with thermal neutrons.It was subsequently measured in a gaseous xenon time projection chamber(GXe TPC)to validate its radioactivity.Our results demonstrate that^(37)Ar is an effective and viable calibration source that offers precise calibration capabilities in the low-energy domain of xenon-based detectors. 展开更多
关键词 ^(37)Ar Gaseous xenon detector LOW-ENERGY Calibration source
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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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A Cross-Band Quantum Light Source Based on Spontaneous Four-Wave Mixing in a Shallow-Ridge Silicon Waveguide
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作者 Yijia Wang Qirui Ren +2 位作者 Zhanping Jin Yidong Huang Wei Zhang 《Chinese Physics Letters》 2026年第1期64-70,共7页
To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.T... To fully utilize the resources provided by optical fiber networks,a cross-band quantum light source generating photon pairs,where one photon in a pair is at C band and the other is at O band,is proposed in this work.This source is based on spontaneous four-wave mixing(SFWM)in a piece of shallow-ridge silicon waveguide.Theoretical analysis shows that the waveguide dispersion could be tailored by adjusting the ridge width,enabling broadband photon pair generation by SFWM across C band and O band.The spontaneous Raman scattering(SpRS)in silicon waveguides is also investigated experimentally.It shows that there are two regions in the spectrum of generated photons from SpRS,which could be used to achieve cross-band photon pair generation.A chip of shallow-ridge silicon waveguide samples with different ridge widths has been fabricated,through which cross-band photon pair generation is demonstrated experimentally.The experimental results show that the source can be achieved using dispersion-optimized shallow-ridge silicon waveguides.This cross-band quantum light source provides a way to develop new fiber-based quantum communication functions utilizing both C band and O band and extends applications of quantum networks. 展开更多
关键词 photon pair generation shallow ridge silicon waveguide spontaneous four wave mixing optical fiber networks adjusting ridge widthenabling cross band quantum light source broadband photon pair generation waveguide dispersion
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基于NCS体系的畲族服饰色彩在现代家具设计中的应用 被引量:3
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作者 胡燕 卢思宇 《林产工业》 北大核心 2025年第6期75-81,共7页
畲族文化源远流长,其服饰色彩体系承载着独特的民族精神与审美意蕴,但在现代设计中的应用面临传承与创新的双重挑战。以NCS色彩体系为理论框架,综合田野调查、实物样本采集与数字化分析等方法,系统提取畲族传统服饰的核心色相与典型色... 畲族文化源远流长,其服饰色彩体系承载着独特的民族精神与审美意蕴,但在现代设计中的应用面临传承与创新的双重挑战。以NCS色彩体系为理论框架,综合田野调查、实物样本采集与数字化分析等方法,系统提取畲族传统服饰的核心色相与典型色彩组合,并通过与NCS色彩体系的科学比对,构建适配现代家具设计的畲族色彩应用框架。研究发现:畲族服饰以青、蓝为主色调,辅以红、黄等高纯度对比色,呈现出高明度、低纯度的整体特征与冷暖对比的和谐美感。基于此,提出“文化内涵融合、科学色彩转化”的应用路径,并开发了家具设计案例。研究成果不仅为现代家具设计注入民族文化基因,拓宽了民族色彩传承的实践维度,也为跨学科的色彩研究提供了方法论参考。 展开更多
关键词 畲族服饰色彩 ncs色彩体系 现代家具设计 应用 色彩设计
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基于NCS体系下的广州深井村建筑色彩研究 被引量:1
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作者 刘栖源 薛颖 孟祥雨 《家具与室内装饰》 北大核心 2025年第5期1-7,共7页
研究以广州市深井村为例,探讨其建筑色彩从广府传统民居到现代城中村住宅的演变特征,分析文化地域性格在色彩演变过程中的重要作用。基于NCS色彩体系,采用动态化视角,对深井古村传统、近代及现代三个时期的建筑立面进行色彩提取识别,建... 研究以广州市深井村为例,探讨其建筑色彩从广府传统民居到现代城中村住宅的演变特征,分析文化地域性格在色彩演变过程中的重要作用。基于NCS色彩体系,采用动态化视角,对深井古村传统、近代及现代三个时期的建筑立面进行色彩提取识别,建立色彩数据库,通过对比各时期建筑立面色彩的黑度、彩度、色相的相关数据,归纳建筑色彩的演变规律。同时,从地域技术特征、社会时代精神和人文艺术品格三个维度,解析色彩演变表征的内在动因。研究发现,深井村的建筑色彩风貌呈现出传统与现代的交织,但在古今建筑色彩风貌差异下,其本征仍反映着广府地区独特的文化地域特征,揭示了文化地域性格对城中村色彩风貌的深远影响。 展开更多
关键词 城中村 建筑色彩 ncs 深井村 文化地域性格
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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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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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Water-soluble organic nitrogen in PM_(2.5) around the Danjiangkou Reservoir:Concentration, sources, and transport pathways 被引量:1
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作者 Chunyan Xiao Pengbo Li +4 位作者 Xiaoshu Chen Tongqian Zhao Xiaoming Guo Yuxiao He Guizhen Wang 《Journal of Environmental Sciences》 2025年第10期757-770,共14页
Water-soluble organic nitrogen(WSON)affects the formation,hygroscopicity,acidity of organic aerosols,and nitrogen biogeochemical cycles.However,qualitative and quantitative characterizations of WSON remain limited due... Water-soluble organic nitrogen(WSON)affects the formation,hygroscopicity,acidity of organic aerosols,and nitrogen biogeochemical cycles.However,qualitative and quantitative characterizations of WSON remain limited due to its chemical complexity.In the study,1-year field samples of particulate matter 2.5(PM_(2.5))were collected fromJune 2022 to May 2023 to analyze the WSON concentration in PM_(2.5),and correlation analysis,positive matrix factor(PMF),and potential source contribution function(PSCF)modelswere employed to elucidate WSON source apportionment and transport pathways.The results revealed that the mean WSON concentrations reached 1.98±2.64μg/m^(3) with a mean WSON to water-soluble total nitrogen(WSTN)ratio of 21%.Further,WSON concentration exhibited a seasonal variation trend,with higher values in winter and lower in summer.Five sources were identified as contributors to WSON in PM_(2.5) within the reservoir area through a comprehensive analysis including correlation analysis,PSCF and concentration weighted trajectory(CWT),and PMF analyses.These sources were agricultural,dust,combustion,traffic,and industrial sources,of which agricultural source emerged as the primary contributor(76.69%).The atmosphere in the reservoir area were primarily influenced by the transport of northeastern air masses,local agricultural activities,industrial cities along the trajectory,and coastal regions,exerting significant influences on the concentration of WSON in the reservoir area.The findings of this study addressed the research gap concerning organic nitrogen in PM_(2.5) within the reservoir area,thereby offering a theoretical foundation and data support in controlling nitrogen pollution in the Danjiangkou Reservoir area. 展开更多
关键词 PM_(2.5) Water-soluble organic nitrogen source apportionment Potential source location Danjiangkou 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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Source apportionment of PM_(2.5) using dispersion normalized positive matrix factorization(DN-PMF)in Beijing and Baoding,China 被引量:1
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作者 Ilhan Ryoo Taeyeon Kim +6 位作者 Jiwon Ryu Yeonseung Cheong Kwang-joo Moon Kwon-ho Jeon Philip K.Hopke Seung-Muk Yi Jieun Park 《Journal of Environmental Sciences》 2025年第9期395-408,共14页
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque... Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities. 展开更多
关键词 source apportionment Dispersion normalized positive matrix factorization Adjacent cities Inter-city impact source location Heating season Air quality management
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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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Denitrification enhanced by composite carbon sources in AAO-biofilter:Efficiency and metagenomics research 被引量:1
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作者 Fan Guo Guokai Yan +8 位作者 Haiyan Wang Lingling Shi Yanjie Zhang Yu Ling Youfang Wei Huan Wang Weiyang Dong Yang Chang Ziyang Tian 《Journal of Environmental Sciences》 2025年第4期25-35,共11页
Nitrogen removal from domestic sewage is usually limited by insufficient carbon source and electron donor.An economical solid carbon source was developed by composition of polyvinyl alcohol,sodium alginate,and corncob... Nitrogen removal from domestic sewage is usually limited by insufficient carbon source and electron donor.An economical solid carbon source was developed by composition of polyvinyl alcohol,sodium alginate,and corncob,which was utilized as external carbon source in the anaerobic anoxic oxic(AAO)-biofilter for the treatment of low carbon-to-nitrogen ratio domestic sewage,and the nitrogen removal was remarkably improved from 63.2%to 96.5%.Furthermore,the effluent chemical oxygen demand maintained at 35 mg/L or even lower,and the total nitrogenwas reduced to less than 2mg/L.Metagenomic analysis demonstrated that the microbial communities responsible for potential denitrification and organic matter degradation in both AAO and the biofilter reactors were mainly composed of Proteobacteria and Bacteroides,respectively.The solid carbon source addition resulted in relatively high abundance of functional enzymes responsible for NO_(3)^(−)-N to NO_(2)^(−)-N con-version in both AAO and the biofilter reactors,thus enabled stable reaction.The carbon source addition during glycolysis primarily led to the increase of genes associated with the metabolic conversion of fructose 1.6P2 to glycerol-3P The reactor maintained high abun-dance of genes related to the tricarboxylic acid cycle,and then guaranteed efficient carbon metabolism.The results indicate that the composite carbon source is feasible for denitri-fication enhancement of AAO-biofilter,which contribute to the theoretical foundation for practical nitrogen removal application. 展开更多
关键词 AAO BIOFILTER Composite carbon source Nitrogen removal METAGENOMICS
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Exploring the diversity of dissolved organic matter(DOM)properties and sources in different functional areas of a typical macrophyte-derived lake combined with optical spectroscopy and FT-ICR MS analysis 被引量:1
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作者 Kun Wang Haoyu Ren +2 位作者 Shengwu Yuan Xia Jiang Pengfei Wang 《Journal of Environmental Sciences》 2025年第1期462-473,共12页
Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and ... Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems.In this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional areas.Our findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA.Ultrahigh-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of DOM.DOM properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel test.The connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and TA.Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management. 展开更多
关键词 Dissolved organic matter Fluorescence property Molecular composition source
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Changes in source contributions to the oxidative potential of PM_(2.5)in urban Xiamen,China 被引量:1
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作者 Jia-Min Li Si-Min Zhao +3 位作者 Qi-Yu Miao Shui-Ping Wu Jie Zhang James J.Schwab 《Journal of Environmental Sciences》 2025年第3期342-357,共16页
The toxicity of PM_(2.5)does not necessarily change synchronously with its mass concentration.In this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothr... The toxicity of PM_(2.5)does not necessarily change synchronously with its mass concentration.In this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothreitol assay,DTT)of PM_(2.5)were investigated in 2017/2018 and 2022 in Xiamen,China.The decrease rate of volume-normalized DTT(DTTv)(38%)was lower than that of PM_(2.5)(55%)between the two sampling periods.However,the mass-normalized DTT(DTTm)increased by 44%.Clear seasonal patterns with higher levels in winter were found for PM_(2.5),most chemical constituents and DTTv but not for DTTm.The large decrease in DTT activity(84%−92%)after the addition of EDTA suggested that watersoluble metals were the main contributors to DTT in Xiamen.The increased gap between the reconstructed and measured DTTv and the stronger correlations between the reconstructed/measured DTT ratio and carbonaceous species in 2022were observed.The decrease rates of the hazard index(32.5%)and lifetime cancer risk(9.1%)differed from those of PM_(2.5)and DTTv due to their different main contributors.The PMF-MLR model showed that the contributions(nmol/(min·m^(3)))of vehicle emission,coal+biomass burning,ship emission and secondary aerosol to DTTv in 2022 decreased by 63.0%,65.2%,66.5%,and 22.2%,respectively,compared to those in 2017/2018,which was consistent with the emission reduction of vehicle exhaust and coal consumption,the adoption of low-sulfur fuel oil used on board ships and the reduced production of WSOC.However,the contributions of dust+sea salt and industrial emission increased. 展开更多
关键词 Chemical composition Oxidative potential Interannual change PMF-MLR source apportionment
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Anthropogenic sources and air mass transport affect spatial and seasonal variations of ambient halocarbons in southeastern China 被引量:1
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作者 Zhaoyang Wu Zhiwei Cao +4 位作者 Xinyi Huang Yonglong Lu Pei Wang Zian Liang Xupeng An 《Journal of Environmental Sciences》 2025年第6期340-352,共13页
Halocarbons play a vital role in ozone depletion and global warming,and are regulated by the Montreal Protocol(MP)and its amendments.China has been identified as an important contributor to the halocarbon emissions,bu... Halocarbons play a vital role in ozone depletion and global warming,and are regulated by the Montreal Protocol(MP)and its amendments.China has been identified as an important contributor to the halocarbon emissions,but the regional sources of halocarbons in China are not yet well comprehended.To investigate the characteristics,emissions,and source profiles,this study conducted a field campaign in Xiamen,a coastal city in southeastern China.Higher enhancements were found in the unregulated halocarbons(CH_(3)Cl,CH_(2)Cl_(2),CHCl_(3))than in the MP eliminated species(CCl_(4),CH_(3)Br)and theMP controlled species(HCFCs,HFCs).Many of the measured halocarbons varied seasonally and regionally,depending on the anthropogenic sources and atmospheric transport.Backward trajectory analysis showed that the air masses from inland were polluted over Shandong,Hebei,and northern Fujian in the cold season,while the air masses fromthe sea in the warm season were clean.Different air masses in two seasons were associated with the halocarbon patterns in the study area.Industrial activities,especially solvent usage,were the primary sources of halocarbons.The emission hot spots in Fujian Province were concentrated in Sanming,Fuzhou,and Xiamen,and the unregulated halocarbons made the largest contribution.This study provides an insight for a deep understanding of the characteristics and potential sources of halocarbons,and for strengthened management of halocarbons in China. 展开更多
关键词 HALOCARBONS source apportionment Southeastern China Seasonal variations Montreal Protocol
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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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