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Spectrum-Flexible Green Light Source Based on SC-PPLN and Superfluorescent Fiber Source 认领 引用
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作者 Junhong HE Jun YE +9 位作者 Yanzhao KE Yidong GUO Xiaoya MA Yang ZHANG Junrui LIANG Lei DU Jinhai ZOU Jiangming XU Jinyong LENG Pu ZHOU 《Photonic Sensors》 SCIE EI CSCD 2026年第2期1-9,共9页
The green light source with tailorable temporal coherence has been widely applied in sensing,optical coherence tomography,speckle-free imaging,and partial coherent applications.In this paper,based on a tunable superfl... The green light source with tailorable temporal coherence has been widely applied in sensing,optical coherence tomography,speckle-free imaging,and partial coherent applications.In this paper,based on a tunable superfluorescent fiber source,we extend the ability of spectral regulation and temporal coherent tunability to the green light band through the second harmonic generation in a step-chirped periodically poled lithium niobate(SC-PPLN)crystal.The wavelength can be tuned from 517.2 nm to 540.0 nm,and the temporal coherence can be controlled by adjusting the bandwidth from 0.23 nm to 13.00 nm.Moreover,we further investigate the output performance at different temperatures and indicate that the appropriate operation wavelength and bandwidth contribute to better power stability under temperature variation.Our work may provide a flexible tunable source for optical coherence tomography,fluorescent imaging,spectroscopy,and so on. 展开更多
关键词 Frequency conversion green light temporal coherence PPLN superfluorescent fiber source
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Changes in source-specific health risks of PM2.5-bound trace elements after the residential“coal-to-gas”conversion measure in urban Beijing 认领 引用
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作者 Wei Yuan Ru-Jin Huang +6 位作者 Jing Duan Jie Guo Wenjuan Cao Ting Wang Jingye Ren Yanan Zhan Wei Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第8期436-442,共7页
The concentration of atmospheric fine particles(PM2.5)has been considerably lowered in Beijing as a result of the implementation of a number of air pollution control initiatives.Nevertheless,the understanding of th... The concentration of atmospheric fine particles(PM2.5)has been considerably lowered in Beijing as a result of the implementation of a number of air pollution control initiatives.Nevertheless,the understanding of the impact of clean air measures on the health risks of PM2.5-bound trace elements is still limited.In this study,the concentrations and chemical fractionation of 14 trace elements in PM2.5 in Beijing after the"coal-to-gas"conversion measure were measured and compared with our previous study in Beijing before the measure.The major elements changed from Fe,Zn,and Pb before the measure to Fe,Ti,and Cu after the measure.The bioavailability of Pb,Zn,Cu,Sr,Ba,and Cr increased by approximately 5%-44%after the measure,while the bioavailability of Cd,Mn,As,Co,V,Fe,Ni,and Ti decreased by approximately 0.5%-31%,which may be mainly attributed to changes in their emission sources.After the measure,the relative contribution of traffic-related emissions to the total concentration of 14 elements increased by 12.1%,and coal combustion decreased by 17.5%.Trafficrelated emissions(92.8%)were the primary causes of carcinogenic risk after the measure,while traffic-related emissions(52.2%)and coal combustion(41.4%)dominated before the measure.This study elucidates changes in concentrations,chemical fractionation,bioavailability,sources,and health risks of PM2.5-bound trace elements in Beijing before and after the“coal-to-gas”conversion measure and suggests that traffic-related emissions should still be the main focus in the future. 展开更多
关键词 Trace elements Chemical fractionation Emission sources Health risks “Coal-to-gas”conversion measure
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Exploring the thermal evolution of highly-to over-mature source rocks using Raman spectroscopy and geochemical signatures 认领 引用
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作者 Fu-hua Shang Xiao-peng Sun +3 位作者 Shu-wei Ma Yu-tong Pang Guan-qun Zhou Ke Miao 《China Geology》 CAS CSCD 2026年第1期75-85,共11页
This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical ... This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(RD/G)and vitrinite reflectance(Ro). 展开更多
关键词 Raman spectroscopy Overmature source rock Qiongzhusi Formation Longmaxi Formation Anthracite Mineral exploration engineering
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Hydraulic erosion response of pika mound slopes to vegetation restoration in the source region of the Yellow River 认领 引用
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作者 JIANG Chengdong LI Guorong +6 位作者 TONG Shengchun LI Jinfang LI Xilai ZHU Haili LIU Yabin CHEN Wenting HU Xiasong 《Journal of Mountain Science》 SCIE CSCD 2026年第4期1457-1475,共19页
This study employed artificial simulated rainfall erosion experiments to investigate the response mechanisms of plateau pika mound patches to soil erosion and nutrient loss in the alpine meadow region of Henan County,... This study employed artificial simulated rainfall erosion experiments to investigate the response mechanisms of plateau pika mound patches to soil erosion and nutrient loss in the alpine meadow region of Henan County,Qinghai Province,China.The objectives were to elucidate the hydraulic erosion characteristics of pika mound patches,the patterns of soil nutrient loss during different vegetation recovery stages,and the influence of vegetation recovery on slope hydraulic erosion.The results showed that:(1)With increasing slope gradient,both the physicalmechanical properties and biological characteristics of soil in pika mound patches declined under the same recovery period.However,under identical slope gradients with varying recovery periods,soil loss volume initially increased and then decreased with rainfall duration,with the 15–20 min interval identified as the sensitive period for soil loss;soil sediment yield exhibited a sharp initial increase followed by a gradual decline,peaking between 20 and 25 min.(2)Nutrient loss rates followed the order:organic matter>available potassium>total potassium>alkali-hydrolyzable nitrogen>available phosphorus>total nitrogen>total phosphorus.Soil nutrient loss was most pronounced during the 2–3 year recovery period.Average flow velocity,Reynolds number,and Manning’s roughness coefficient were identified as the primary controlling factors influencing soil nutrient loss.(3)Correlation analysis revealed a significant negative relationship(P<0.05)between the biotic characteristics of rodent mound patches and soil loss rates.Runoff width,average flow velocity,Reynolds number,and Manning’s roughness coefficient were all significant factors influencing soil nutrient loss(P<0.05).(4)Structural equation modeling indicated that vegetation and soil properties significantly altered slope hydrodynamics,with vegetation characteristics in pika mound patches exerting indirect effects by influencing soil physical and mechanical properties.The study demonstrates that during vegetation recovery,pika mound patches in alpine regions enhance erosion suppression over time through improved soil and biological properties,thereby effectively reducing soil erosion risk. 展开更多
关键词 Hydraulic erosion Hydrodynamic properties Nutrient loss Soil physicochemical properties,Pika mounds Yellow River source area
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Multi-source hydrocarbon accumulation in the faulted and deeply depressed Tangdong area,Qikou Sag,Bohai Bay Basin 认领 引用
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作者 Xiugang Pu Guochao Xia +6 位作者 Jiangchang Dong Zhannan Shi Wenzhong Han Qianru Shi Wei Zhang Yueqi Dong Xiongying Dong 《Energy Geoscience》 EI CAS CSCD 2026年第2期85-100,共16页
Based on organic geochemical analysis data,this study examined the characteristics of multi-source hydrocarbon accumulation in the Tangdong area of Qikou Depression,Bohai Bay Basin.The results indicate that the Tangdo... Based on organic geochemical analysis data,this study examined the characteristics of multi-source hydrocarbon accumulation in the Tangdong area of Qikou Depression,Bohai Bay Basin.The results indicate that the Tangdong area contains four source rock sequences:the third member of the Dongying Formation(Ed3),the middle and lower sub-members of the first and third member of Shahejie Formation(Es 1M,Es 1L,Es 3).Both the salinity of sedimentary water bodies and the contribution of bacteria in the four source rock sequences gradual increase in the order of Es 3,Es 1M,Es 1L and Ed3,as indicated by the Ga/C30H,ETR,sterane/C30 hopane,C24TeT/C26TT,C23TT/C30H,and the carbon isotope data of group components.Additionally,certain quantities of 4-methylsterane have been detected in source rocks in the Es 3,Es 1M,and Ed3,suggesting the special contribution of dinoflagellates to these source rocks.Based on biomarker parameters and carbon isotope data,the crude oil can be categorized into classes A to D,which show complex multi-source accumulation characterized by different sources in the same well and even in the same layer.Class A crude oil occurring in the higher part of the Ed3 originates from source rocks in the Es 1L and Es 3.Class B oil existing in the lower part of the Ed3 is derived from source rocks in the Ed3.Class C oil found in the Es 1U is sourced from source rocks in the Es 1M.Class D oil present in the Es 1L is contributed indigenously by the source rocks in the Es 1L,establishing this unit as a lithologic hydrocarbon reservoir with source rocks and reservoirs in the same layer.Under the guidance of the understanding of multi-source hydrocarbon accumulation,currently,three wells have been drilled,all yielding satisfactory outcomes. 展开更多
关键词 Oil-source rock correlation Multi-source hydrocarbon accumulation Petroleum geochemistry Source rock Deeply depressed area Qikou sag Exploration well emplacement
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A statistical model for predicting rock avalanche runout using source area width from 63 representative cases 认领 引用
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作者 Rui-chen Chen Jian Chen +2 位作者 Sheng Ma Zi-ang Yan Qian Shi 《China Geology》 CAS CSCD 2026年第2期366-382,共17页
Developing predictive models for rock avalanche runout is crucial for hazard risk mitigation and management,while also deepening the understanding of rock avalanche dynamics.In this study,a database of 63 representati... Developing predictive models for rock avalanche runout is crucial for hazard risk mitigation and management,while also deepening the understanding of rock avalanche dynamics.In this study,a database of 63 representative rock avalanches was compiled,and the geometric characteristics of these events were analyzed.Traditional regression methods were compared with neural network regression(NNR)approaches to find the optimal model.Model parameters,loss functions,and evaluation metrics were examined to determine optimal configurations.Based on correlation analyses and model performance,this study recommends the use of source area width as an alternative to failure volume in runout prediction models,effectively addressing the common challenge of estimating avalanche volume.Ultimately,an NNR-based model,utilizing mean squared logarithmic error as the loss function and incorporating source area width and fall height as input parameters,was identified as the optimal approach.This model achieved prediction errors within a−50% to 50% range with 95.2% probability,yielding a mean absolute percentage error of 23.22% and an R2 of 0.85.These findings enhance rock avalanche prediction methodologies,providing more accurate tools for assessing the potential impact zones of destructive geological events. 展开更多
关键词 Runout prediction model Rock avalanche Traditional regression Neural network regression Source area width Fall height Loss functions Prediction errors Geological hazard prevention and control engineering
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Natural resources, chemical synthesis, chemo-bio transformations, metabolism,pharmacology, toxicology, and the underlying mechanisms of curdione 认领 引用
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作者 Suyan Liu Jiayin Han +4 位作者 Yushi Zhang Dewen Liu Jintang Cheng Chen Pan Aihua Liang 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2026年第3期257-269,共13页
Curcuma is a traditional Chinese medicine that has been utilized for centuries in the treatment of various diseases. Terpenoids, particularly monoterpenes and sesquiterpenes, constitute the primary bioactive component... Curcuma is a traditional Chinese medicine that has been utilized for centuries in the treatment of various diseases. Terpenoids, particularly monoterpenes and sesquiterpenes, constitute the primary bioactive components of the essential oil derived from Curcuma species.Among these, curdione—one of the key active constituents—has been identified in 25 Curcuma species, with the highest concentration reported in the rhizome essential oil of Curcuma trichosantha Gagnep. Curdione can also be synthesized through chemical methods,and its regio-and stereo-selectivity can be further optimized via chemo-bio transformations.This compound demonstrates significant therapeutic potential, including anticancer, antithrombotic, anti-inflammatory, anti-viral, anti-fungal, anti-diabetic, and multi-organ protective properties. Despite these promising biological activities, its clinical application is hindered by poor water solubility and potential toxicity. This review summarizes current knowledge on the natural sources, chemical synthesis, chemo-bio transformations, metabolism, pharmacokinetics, pharmacological effects, potential toxicities, and molecular mechanisms of curdione. Furthermore, perspectives on future drug development are discussed with the aim of promoting the clinical translation of this promising natural compound. 展开更多
关键词 Curdione Source Metabolism Bioactivity Toxicity Mechanism
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Recent advancements in butyric acid research:health effects,sources,and high-efficiency bioconversion production strategies 认领 引用
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作者 Zhipeng Zhou Xinyu Wang +6 位作者 Yujie Zhong Shengbao Cai Zhijia Liu Yanfei Wang Xiaosong Hu Tao Wang Junjie Yi 《Food Science and Human Wellness》 SCIE CAS CSCD 2026年第3期999-1012,共14页
Butyric acid,a representative short-chain fatty acid,has gained considerable attention due to its noteworthy health benefits and widespread application.Nonetheless,the majority of commercially available butyric acid i... Butyric acid,a representative short-chain fatty acid,has gained considerable attention due to its noteworthy health benefits and widespread application.Nonetheless,the majority of commercially available butyric acid is currently synthesized through environmentally harmful chemical synthesis methods,which pose a significant obstacle to the development of the butyric acid industry.Therefore,there is a need to develop cost-effective,efficient,and environmentally friendly methods for butyric acid production.This review commences with a systematic evaluation of the health effects and mechanisms of action of butyric acid.Subsequently,it outlines the advantages and disadvantages of different sources of butyric acid,including chemical synthesis and biosynthesis,along with their development trends.Finally,the review delves into high-efficiency strategies to enhance butyric acid production through targeted biosynthesis.This review not only serves as a valuable reference for researchers and practitioners interested in the diverse aspects of butyric acid but also offers insights into future trends in the development of butyric acid. 展开更多
关键词 Butyric acid Health effects Sources Bioconversion production strategies
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Topographically corrected land surface temperatures reveal a 2005 regime shift and prolonged thawing in the Yellow River Source Region(1981-2020) 认领 引用
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作者 LI Hongying CUI Yingying +4 位作者 WANG Shengzhen YANG Yang CHEN Chaorong ZHOU Qiang LIU Fenggui 《Journal of Mountain Science》 SCIE CSCD 2026年第6期2650-2670,共21页
The source area of the Yellow River(SAYR)is a critically important cryospheric region highly sensitive to climate warming.However,capturing fine-scale thawing–freezing dynamics remains challenging due to the region&#... The source area of the Yellow River(SAYR)is a critically important cryospheric region highly sensitive to climate warming.However,capturing fine-scale thawing–freezing dynamics remains challenging due to the region's rugged topography and sparse observational networks.In this study,we developed a 1-km,40-year(1981–2020)dataset of surface temperatures and thawing–freezing indices by applying month-specific topographic corrections to ERA5-Land reanalysis data.Validation against independent station observations yielded a root mean square error(RMSE)of 1.49℃,and uncertainty assessments demonstrate that the monthly-derived indices capture interannual trends with high consistency(R2>0.97).Over the past four decades,regional freezing indices have significantly decreased,while thawing indices have increased,resulting in an extension of the average thawing duration by 1.17 days per decade.Furthermore,a regime shift detected in 2005 prolonged the annual thawing duration by 14.8 days,extending the unfrozen soil period and potentially enhancing moisture infiltration into the subsurface.Spatially,this thawing intensification is most pronounced in the southeastern valleys,whereas changes in the thermal regime over the northwestern and central highlands indicate intensified ground warming,which is likely associated with permafrost degradation and active-layer deepening.Overall,this high-resolution dataset offers an improved representation of surface thermal processes compared to traditional air-temperature-based proxies,providing valuable support for climate adaptation and infrastructure planning in this critical headwater region. 展开更多
关键词 Source Area of the Yellow River Thawing–Freezing indices Permafrost degradation High-resolution(1-km) Topographic correction Climate change
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High-contrast and high-resolution X-ray phase-contrast imaging based on betatron sources driven by a laser wakefield accelerator 认领 引用
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作者 Sijie Fan Jiaxing Wen +18 位作者 Hansheng Ye Hang Guo Sixin Wu Mao Peng Gaojie Zeng Xiangjun Xiang Tao Zhu Qiang Gong Lai Wei Shaoyi Wang Bo Zhang Yuchi Wu Song Li Xianfeng Shen Zhentian Wang Wentao Wang Shuke Huang Wenhui Huang Zongqing Zhao 《Matter and Radiation at Extremes》 SCIE EI CAS CSCD 2026年第4期59-70,共12页
X-ray phase-contrast imaging(XPCI)provides superior sensitivity for the diagnosis of low-Z materials compared with absorption-based techniques.Betatron radiation generated by laser wakefield accelerators,which offers ... X-ray phase-contrast imaging(XPCI)provides superior sensitivity for the diagnosis of low-Z materials compared with absorption-based techniques.Betatron radiation generated by laser wakefield accelerators,which offers high photon flux,ultra-short duration,and relatively high spatial coherence,is a promising compact source for XPCI.At present,there is a lack of knowledge about how to control wakefield accelerators and realize high-quality XPCI.This study investigates the influence of gas pressure(plasma density)on betatron source characteristics and on the performance of propagation-based XPCI.Through particle-in-cell and wave-optics simulations,it explores the relationship between gas pressure and imaging characteristics such as spatial resolution and brightness and determines an optimal operation window.Experimental results confirm this optimal operation window at 40-45 psi[plasma density~(3-4)×1018cm^-3],with which a peak photon flux of 8×1012photons/sr and a contrast of 20.32%at a spatial resolution of 5μm are realized.This study demonstrates a pathway for the optimization of betatron-based XPCI,enabling synchrotron-comparable spatial resolution in a laboratory-scale setup and shows the potential of XPCI in ultrafast microscopic imaging applications. 展开更多
关键词 high contrast low z materials laser wakefield accelerator photon flux betatron sources high resolution x ray phase contrast imaging laser wakefield acceleratorswhich
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Fully Distributed Reinforcement Learning for Efficient Networked Microgrids Resource Management:Source-Load-Storage Coordination 认领 引用
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作者 Xiaowen Wang Xinquan Shao Shuai Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2026年第7期1755-1757,共3页
Dear Editor,This letter proposes a fully distributed multi-agent reinforcement learning(DMARL)algorithm for the coordinated optimization and scheduling of source-load-storage in networked microgrids.To accommodate the... Dear Editor,This letter proposes a fully distributed multi-agent reinforcement learning(DMARL)algorithm for the coordinated optimization and scheduling of source-load-storage in networked microgrids.To accommodate the rapid development of networked microgrids,we have designed a DMARL algorithm with an event-triggered mechanism(ETM).Unlike centralized approaches,DMARL empowers individual agents to cooperatively learn and optimize based only on local observations,while reducing the communication burden.Simulation results validate the performance of the proposed algorithm,demonstrating its effectiveness in efficient microgrid resource management. 展开更多
关键词 multi agent reinforcement learning source load storage coordination networked microgridswe cooperatively learn networked microgridsto event triggered mechanism centralized approachesdmarl fully distributed reinforcement learning
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Research on the implementation of dust pollution source control measures in light industry workshops 认领 引用
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作者 GUO Fang 《外文科技期刊数据库（文摘版）自然科学》 2026年第1期121-125,共5页
Dust pollution in light industry workshops poses a continuous threat to occupational health and safety in production, and the traditional terminal treatment mode has limitations. This study introduces the concept of s... Dust pollution in light industry workshops poses a continuous threat to occupational health and safety in production, and the traditional terminal treatment mode has limitations. This study introduces the concept of source domain management and control to build a systematic prevention and control system. The physical and chemical characteristics and diffusion law of dust were analyzed by literature induction and field measurement;Mass balance and numerical simulation are used to identify the main source regions and quantify their contributions;Then the system design covers the integrated control measures of source suppression, transmission interruption and regional purification. The study found that the differentiated management and control strategy based on the priority of process source strength, combined with the optimization of air distribution, can significantly improve the overall governance efficiency. The research results provide a complete path from theory to implementation for dust pollution control in light industry. 展开更多
关键词 Light industry workshop Dust pollution Source domain control Process source strength Air distribution
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Research on Mechanism Innovation and Practical Paths of Network Ideological and Political Education in the Context of Diversified Student Sources in Higher Vocational Colleges 认领 引用
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作者 Liangui Li 《Journal of Contemporary Educational Research》 2026年第4期297-303,共7页
Currently,the student body in higher vocational colleges presents a diverse picture,and the traditional ideological and political education model is facing the predicament of weakened effectiveness.Although online ide... Currently,the student body in higher vocational colleges presents a diverse picture,and the traditional ideological and political education model is facing the predicament of weakened effectiveness.Although online ideological and political education is regarded as a key solution,most of the practices still remain at the technical tool level and have not yet touched upon the deep transformation of the educational logic.From the perspective of mechanism operation,this paper diagnoses the inherent deficiencies of current online ideological and political education in higher vocational colleges in four dimensions:motivation,operation,collaboration,and guarantee,and constructs an innovative framework with“data intelligence,platform integration,teacher-student symbiosis,and system collaboration”as its pillars.On this basis,it further proposes a transformation path from“technical embedding”to“value symbiosis,”emphasizing that the core of online ideological and political education does not lie in the change of media,but in the deep reconstruction of educational relationships.Empirical research shows that this framework helps to achieve differentiated allocation of educational resources and the steady improvement of educational process efficiency,providing theoretical and practical references for building a higher vocational online ideological and political education system that is in line with the diverse characteristics of the student body. 展开更多
关键词 Higher vocational colleges Diversified student sources Online ideological and political education Mechanism innovation Precision education
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Coaly source rock evaluation using well logs:The Jurassic Kezilenuer Formation in Kuqa Depression,Tarim Basin,China 认领 引用 被引量：4
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作者 Fei Zhao Jin Lai +6 位作者 Zong-Li Xia Zhong-Rui Wang Ling Li Bin Wang Lu Xiao Yang Su Gui-Wen Wang 《Petroleum Science》 SCIE EI CAS CSCD 2025年第9期3599-3612,共14页
Coaly source rocks have attracted considerable attention for their significant hydrocarbon generation potential in recent years. However, limited study is performed on utilizing geochemical data and well log data to e... Coaly source rocks have attracted considerable attention for their significant hydrocarbon generation potential in recent years. However, limited study is performed on utilizing geochemical data and well log data to evaluate coaly hydrocarbon source rocks. In this study, geochemical data and well log data are selected from two key wells to conduct an evaluation of coaly hydrocarbon source rocks of Jurassic Kezilenuer Formation in Kuqa Depression of Tarim Basin. Initially, analysis was focused on geochemical parameters to assess organic matter type, source rock quality, and hydrocarbon generation potential.Lithology types of source rocks include mudstone, carbonaceous mudstone and coal. The predominant organic matter type identified was Type Ⅲ and Type Ⅱ2, indicating a favorable hydrocarbon generation potential. Well log data are integrated to predict total organic carbon(TOC) content, and the results indicate that multiple regression method is effective in predicting TOC of carbonaceous mudstone and coal. However, the ΔlgR method exhibited limited predictive capability for mudstone source rock.Additionally, machine learning methods including multilayer perceptron neural network(MLP), random forest(RF), and extreme gradient boosting(XGBoost) techniques are employed to predict TOC of mudstone source rock. The XGBoost performs best in TOC prediction with correlation coefficient(R2) of 0.9517, indicating a close agreement between measured and predicted TOC values. This study provides a reliable prediction method of coaly hydrocarbon source rocks through machine learning methods, and will provide guidance for resource assessment. 展开更多
关键词 Source rock Well logs Kuqa Depression Kezilenuer formation Machine learning
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Water-soluble organic nitrogen in PM2.5 around the Danjiangkou Reservoir:Concentration, sources, and transport pathways 认领 引用 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》 SCIE EI CAS CSCD 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(PM2.5)were collected fromJune 2022 to May 2023 to analyze the WSON concentration in PM2.5,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/m3 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 PM2.5 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 PM2.5 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 PM2.5 Water-soluble organic nitrogen Source apportionment Potential source location Danjiangkou Reservoir
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Denitrification enhanced by composite carbon sources in AAO-biofilter:Efficiency and metagenomics research 认领 引用 被引量：2
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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》 SCIE EI CAS CSCD 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 NO3−-N to NO2−-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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Restoration of hydrocarbon generation potential of the highly mature Lower Cambrian Yuertusi Formation source rocks in the Tarim Basin 认领 引用 被引量：3
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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》 SCIE EI CAS CSCD 2025年第2期588-606,共19页
The Early Cambrian Yuertusi Formation(Є1y)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(Є1y)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 ofЄ1y 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 theЄ1y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×1010t,the cumulative hydrocarbon expulsion is 35.59×1010t,and the cumulative residual hydrocarbon is 33.29×1010t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ1y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ1y 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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Response of precipitation isotopes and water vapor sources to regional climate change on the Gannan Plateau,China 认领 引用 被引量：2
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作者 CHEN Fenli KANG Nan +4 位作者 WANG Shengjie GAO Minyan ZHANG Qiuyan LI Huizhen YAO Yiwen 《Journal of Arid Land》 SCIE CSCD 2025年第4期440-456,共17页
Precipitation isotopes(δ18O and δ2H)are closely related to meteorological conditions for precipitation generation and the initial state of water vapor source areas,and are essential to the study of the regiona... Precipitation isotopes(δ18O and δ2H)are closely related to meteorological conditions for precipitation generation and the initial state of water vapor source areas,and are essential to the study of the regional hydrological cycle.The deuterium excess(d-excess)indicates deviation in isotope fractionation during evaporation and can trace water vapor sources.This study analyzed 443 precipitation samples collected from the Gannan Plateau,China in 2022 to assess precipitation isotope variations and their driving factors.Water vapor sources were evaluated using the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT),Concentration Weighted Trajectory(CWT),and Potential Source Contribution Factor(PSCF)models.Results showed that precipitation isotope values showed significant spatial and temporal variations on the Gannan Plateau.Temporally,precipitation isotope values peaked in June(when evaporation dominated)and minimized in March(depletion effect of air masses in the westerly wind belt).Spatially,the isotope values showed a distribution pattern of"high in the east and low in the west",which was mainly regulated by the differences in altitude and local meteorological conditions.Compared with the global meteoric water line(GMWL)with equation of δ2H=8.00δ18O+10.00,the slope and intercept of local meteoric water line(LMWL)for precipitation on the Gannan Plateau were smaller(7.49 and 7.63,respectively),reflecting the existence of a stronger secondary evaporation effect under the clouds in the region.The sources of water vapor on the Gannan Plateau showed significant seasonality and spatial heterogeneity.Specifically,the westerly belt and monsoon were the main water vapor transport paths at each sampling point,with Central Asian continental water vapor dominating in spring(53.49%),Indian Ocean water vapor dominating in summer(52.53%),Atlantic Ocean water vapor dominating in autumn(46.74%),and Atlantic Ocean and Mediterranean Sea water vapor dominating in winter(42.30%and 33.68%,respectively).Changes in the intensity of convective activity and Outgoing Longwave Radiation(OLR)affected the enrichment of isotopic values,which exhibited the same change trends as δ18O.During the precipitation process,the δ18O value first decreased and then increased.During the initial and final stages of precipitation process,precipitation was mainly influenced by continental air masses,while during the middle stage,it was controlled by marine air masses.The systematic research on precipitation isotopes and water vapor sources is important for climate change research and extreme precipitation prediction on the Gannan Plateau and other similar areas. 展开更多
关键词 precipitation isotopes deuterium excess(d-excess) water vapor sources Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT) Concentration Weighted Trajectory(CWT) Potential Source Contribution Factor(PSCF) Gannan Plateau
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Characterization and sources of childhood PAEs exposure from residential airborne dust in China cities 认领 引用 被引量：1
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作者 Chao Wang Shuhan Gong +9 位作者 Yun Cao Mengmeng Liu Wenying Zhang Xiaotong Zhang Lin Fan Li Li Hang Du Mats Tysklind Xu Yang Xianliang Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2025年第6期1-13,共13页
To explore the multicenter characteristics of endocrine-like phthalate esters(PAEs)in household dust and propose effective control strategies for global indoor public health.An on-site observational investigation was ... To explore the multicenter characteristics of endocrine-like phthalate esters(PAEs)in household dust and propose effective control strategies for global indoor public health.An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019.A total of 246 household dust sampleswere collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry(GC-MS).Questionnaires were used to gather information on building conditions,indoor behaviors,and ventilation habits.In residential dust from the nine cities,the total concentrations of the ten PAE congeners(PAEs)ranged from 0.921 to 29097.297μg/g.Dicyclohexyl phthalate(DCHP)and di(2-ethylhexyl)phthalate(DEHP)were the dominant congeners inPAEs.Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation,with a carcinogenic risk of 5.47×10−6 for DEHP exposure in household dust.HigherPAEs concentrations were associated with higher temperature,double glazing,wall paint usage,television and computer use,and indoor plant growth.This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions.Effective mitigation measures based on household-related information,residential characteristics,decoration materials,and lifestyle should be taken to build a healthy household environment. 展开更多
关键词 Phthalate esters Household dust Source analysis Health risk Influencing factors
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Variability of long-term terrestrial water storage changes and its environmental effects in the Three Rivers Source Region,China 认领 引用 被引量：1
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作者 LU Houliang ZUO Huimin +2 位作者 ZHOU Han JIAO Yufei HU Xiaonong 《Journal of Mountain Science》 SCIE CSCD 2025年第7期2439-2457,共19页
Climate change and anthropogenic activities have driven significant terrestrial water storage changes(TWSC)in the Three Rivers Source Region(TRSR),exerting profound impacts on freshwater availability across China and ... Climate change and anthropogenic activities have driven significant terrestrial water storage changes(TWSC)in the Three Rivers Source Region(TRSR),exerting profound impacts on freshwater availability across China and broader Asia.However,long-term TWSC characterization remains challenging due to limited observational data in this alpine region.Here,we integrate GRACE observations(2002-2020),ERA5-Land reanalysis,and GLDAS data to reconstruct TWSC using two methods:(1)the water balance method(PER)and(2)the component summation method(SS),applied to three input datasets(ERA5-Land,GLDAS,and their average,GLER).Comparative analysis reveals that the SS method applied to GL-ER yields the highest consistency with GRACE-derived TWSC.Using this optimal approach,we extend the analysis to 1951~2020,uncovering spatiotemporal TWSC patterns.Although annual TWSC trends appear negligible due to strong seasonality,we introduce the intra-year TWSC fluctuation(TWSCF)index to quantify cumulative variability.A significant(p<0.05)transition occurred in 1980,with TWSCF shifting from a declining trend(-0.39 mm/yr)to an increasing trend(0.56 mm/yr),primarily driven by soil moisture changes.However,Hurst exponent analysis suggests this upward trend may not persist.Drought and vegetation assessments indicate concurrent wetting and greening in the TRSR.TWSC correlates strongly with meteorological drought,acting as a reliable drought indicator while its linkage with vegetation dynamics suggests a potential contribution to greening.Our findings provide a robust framework for understanding long-term TWSC evolution and its hydrological-ecological interactions under climate change. 展开更多
关键词 Three Rivers Source Region Terrestrial water storage changes GRACE Dataset reconstruction Mutation analysis
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