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Thermal hazard comparison and assessment of Li-ion battery and Na-ion battery 被引量:6
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作者 Wenxin Mei Zhixiang Cheng +5 位作者 Longbao Wang Anqi Teng Zhiyuan Li Kaiqiang Jin Jinhua Sun Qingsong Wang 《Journal of Energy Chemistry》 2025年第3期18-26,共9页
Na-ion batteries are considered a promising next-generation battery alternative to Li-ion batteries,due to the abundant Na resources and low cost.Most efforts focus on developing new materials to enhance energy densit... Na-ion batteries are considered a promising next-generation battery alternative to Li-ion batteries,due to the abundant Na resources and low cost.Most efforts focus on developing new materials to enhance energy density and electrochemical performance to enable it comparable to Li-ion batteries,without considering thermal hazard of Na-ion batteries and comparison with Li-ion batteries.To address this issue,our work comprehensively compares commercial prismatic lithium iron phosphate(LFP) battery,lithium nickel cobalt manganese oxide(NCM523) battery and Na-ion battery of the same size from thermal hazard perspective using Accelerating Rate Calorimeter.The thermal hazard of the three cells is then qualitatively assessed from thermal stability,early warning and thermal runaway severity perspectives by integrating eight characteristic parameters.The Na-ion cell displays comparable thermal stability with LFP while LFP exhibits the lowest thermal runaway hazard and severity.However,the Na-ion cell displays the lowest safety venting temperature and the longest time interval between safety venting and thermal runaway,allowing the generated gas to be released as early as possible and detected in a timely manner,providing sufficient time for early warning.Finally,a database of thermal runaway characteristic temperature for Li-ion and Na-ion cells is collected and processed to delineate four thermal hazard levels for quantitative assessment.Overall,LFP cells exhibit the lowest thermal hazard,followed by the Na-ion cells and NCM523 cells.This work clarifies the thermal hazard discrepancy between the Na-ion cell and prevalent Li-ion cells,providing crucial guidance for development and application of Na-ion cell. 展开更多
关键词 Li-ion battery Na-ion battery Thermal runaway Characteristic parameters Thermal hazard assessment
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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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An integrated approach for GLOF hazard,vulnerability and risk assessment in the Karakoram Mountain Range of northern Pakistan 被引量:1
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作者 Sajid ULLAH Muhammad SHAFIQUE +2 位作者 Ghazanfar Ali KHATTAK Attaullah SHAH Yaseen ULLAH 《Journal of Mountain Science》 2025年第1期142-155,共14页
Climate change and rising temperatures are accelerating the rate of deglaciation in the Hindu Kush Karakoram Himalaya(HKH)ranges,leading to the formation of new glacial lakes and the expansion of existing ones.These l... Climate change and rising temperatures are accelerating the rate of deglaciation in the Hindu Kush Karakoram Himalaya(HKH)ranges,leading to the formation of new glacial lakes and the expansion of existing ones.These lakes are often vulnerable to failure,posing a significant threat to downstream communities and infrastructure.Therefore,a comprehensive assessment of Glacier-Lake Outburst Flood(GLOF)hazards and risk assessment is crucial to evaluate flood runout characteristics and identify settlements and infrastructure that are exposed and vulnerable to floods,aiding in the development and implementation of risk reduction strategies.This study aims to simulate a GLOF event induced by the Shisper glacier lake in northern Pakistan,using the HEC-RAS,and to assess its impact on settlements,infrastructure,and agricultural land.For the hydrometeorological analysis of the GLOF event,topographic data from unmanned aerial vehicles(UAVs),stream profiles,discharge data,Manning's roughness coefficient(n),and land use/land cover(LULC)were analyzed using HEC-RAS and geographic information system(GIS).During the GLOF event on May 7,2022,a maximum water depth of 6.3 m and a maximum velocity of 9.5 m/s were recorded.Based on the runout characteristics of this event,vulnerability and risk assessments have been calculated.The physical,social,and environmental vulnerabilities of the at-risk elements were evaluated using the analytical hierarchy process(AHP)and integrated with the hazard data to develop a risk map.The study identified the areas,infrastructure and settlements susceptible to GLOF hazard to support the development and implementation of targeted and evidence-based mitigation and adaptation strategies. 展开更多
关键词 GLOF hazard assessment Glacial lake HEC-RAS Vulnerability and risk Shisper glacier
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Occupational Hazard Factors and the Trajectory of Fasting Blood Glucose Changes in Chinese Male Steelworkers Based on Environmental Risk Scores:A Prospective Cohort Study 被引量:1
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作者 Mingxia Zou Wei Du +7 位作者 Qin Kang Yuhao Xia Nuoyun Zhang Liu Feng Feiyue Li Tiancheng Ma Yajing Bao Hongmin Fan 《Biomedical and Environmental Sciences》 2025年第6期666-677,共12页
Objective We aimed to investigate the patterns of fasting blood glucose(FBG)trajectories and analyze the relationship between various occupational hazard factors and FBG trajectories in male steelworkers.Methods The s... Objective We aimed to investigate the patterns of fasting blood glucose(FBG)trajectories and analyze the relationship between various occupational hazard factors and FBG trajectories in male steelworkers.Methods The study cohort included 3,728 workers who met the selection criteria for the Tanggang Occupational Cohort(TGOC)between 2017 and 2022.A group-based trajectory model was used to identify the FBG trajectories.Environmental risk scores(ERS)were constructed using regression coefficients from the occupational hazard model as weights.Univariate and multivariate logistic regression analyses were performed to explore the effects of occupational hazard factors using the ERS on FBG trajectories.Results FBG trajectories were categorized into three groups.An association was observed between high temperature,noise exposure,and FBG trajectory(P<0.05).Using the first quartile group of ERS1 as a reference,the fourth quartile group of ERS1 had an increased risk of medium and high FBG by 1.90and 2.21 times,respectively(odds ratio[OR]=1.90,95%confidence interval[CI]:1.17–3.10;OR=2.21,95%CI:1.09–4.45).Conclusion An association was observed between occupational hazards based on ERS and FBG trajectories.The risk of FBG trajectory levels increase with an increase in ERS. 展开更多
关键词 Fasting blood glucose Occupational hazards Group-based trajectory modeling Environmental risk scores Steelworkers
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Characteristics of Massive Glacier-Related Watershed Geohazard Chains in the Eastern Himalayan Syntaxis,China 被引量:1
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作者 Shaohua Gao Yang Gao +4 位作者 Yueping Yin Bin Li Wenpei Wang Tiantian Zhang Haoyuan Gao 《Journal of Earth Science》 2025年第3期1181-1197,共17页
Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researchin... Frequent glacier-related watershed geohazard chains are causing severe damage to life and infrastructure,reported consistently from the Eastern Himalayan Syntaxis.This paper presents a systematic method for researching geohazard,from regional to individual scale.The methodology includes the establishment of geological chain inventories,discrimination of geohazard chain modes,analyses of dynamics and dam breaches,and risk assessments.The following results were obtained:(1)In the downstream of Yarlung Zangbo River,175 sites were identified as high-risk for river blockage disasters,indicating the development of watershed geohazards.Five geohazard chain modes were summarized by incorporating geomorphological characteristics,historical events,landslide zoning,and materials.The risk areas of typical hazard were identified and assessed using InSAR data.(2)Glacier-related watershed geohazard chains are significantly different from traditional landslides.A detailed inversion analysis was conducted on the massive rock-ice avalanche in the Sedongpu gully in 2021.This particular event lasted roughly 300 seconds,with a maximum flow velocity of 77.2 m/s and a maximum flow height of 93 meters.By scrutinizing the dynamic processes and mechanical characteristics,mobility stages and phase transitions can be divided into four stages.(3)Watershed geohazard chains tend to block rivers.The peak breach discharge of the Yigong Landslide reached 12.4×10^(4) m^(3)/s,which is 36 times the volume of the seasonal flood discharge in the Yigong River.Megafloods caused by landslide dam breaches have significantly shaped the geomorphology.This study offers insights into disaster patterns and the multistaged movement characteristics of glacier-related watershed geohazard chains,providing a comprehensive method for investigations and assessments in glacial regions. 展开更多
关键词 glacier-related watershed geohazard chains geohazard chain modes secondary hazards InSAR Eastern Himalayan Syntax DISASTERS glaciers
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Seismic Hazard Evaluation and Structural Design Guidelines for the Southern Region of Saudi Arabia
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作者 Mohammed Alrubaidi 《Open Journal of Earthquake Research》 2025年第1期7-27,共21页
The southern region of Saudi Arabia exhibits a distinct seismic profile shaped by the Red Sea Rift and local fault systems, necessitating rigorous seismic hazard evaluations and tailored structural design strategies. ... The southern region of Saudi Arabia exhibits a distinct seismic profile shaped by the Red Sea Rift and local fault systems, necessitating rigorous seismic hazard evaluations and tailored structural design strategies. This study applies a robust Probabilistic Seismic Hazard Analysis (PSHA) framework to compute Maximum Considered Earthquake (MCE) and Risk-Targeted Maximum Considered Earthquake (MCER) values for major cities, including Jazan, Abha, and Najran. Utilizing local seismotectonic models, ground motion prediction equations (GMPEs), and soil classifications, the study generates precise ground motion parameters critical for infrastructure planning and safety. Results indicate significant seismic hazard variability, with Jazan showing high seismic risks with an MCER SA (0.2 s) of 0.45 g, compared to Najran’s lower risks at 0.23 g. Structural design guidelines, informed by MCE and MCER calculations, prioritize the integration of site-specific seismic data, enhanced ductility requirements, and advanced analytical methods to ensure resilient and sustainable infrastructure. The study underscores the necessity of localized seismic assessments and modern engineering practices to effectively mitigate seismic risks in this geologically complex region. 展开更多
关键词 Seismic hazard PSHA Maximum Magnitude Rupture Characteristics SA KSA PGA
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Application of dendrogeomorphology in snow avalanche hazard assessment:progress and prospects
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作者 CHEN Guoqing HAO Jiansheng +1 位作者 CUI Peng WANG Yan 《Journal of Mountain Science》 2025年第6期1912-1925,共14页
Snow avalanches present a significant threat to infrastructure,affecting buildings,roads,railways,and power lines,and frequently leading to massive economic losses in livelihoods and production.With the increase in re... Snow avalanches present a significant threat to infrastructure,affecting buildings,roads,railways,and power lines,and frequently leading to massive economic losses in livelihoods and production.With the increase in regional temperatures and the occurrence of extreme snowfall events,the frequency and intensity of avalanches have escalated,resulting in more severe incidents and higher casualty rates.As natural archives of environmental changes,tree rings offer valuable proxies for avalanche hazard assessments in regions where direct observation data is scarce,particularly in high-altitude regions.The dendrogeomorphology has been gradually being applied in avalanche hazard evaluation,however,it remains limited in China.To address this gap,this study systematically investigates the principles and methodologies for reconstructing avalanche histories and evaluates their applications in avalanche hazard assessments through a literature review and field observations.It provides a comprehensive overview of recent advancements in key areas,including the impact of avalanches on forest ecosystems,the reconstruction of avalanches,and the analysis of avalanche events(i.e.,the spatiotemporal distribution,the historical recurrence intervals,magnitudes,and triggering conditions of avalanches).Considering the current limitations in avalanche hazard assessments and the urgent need for such research in China,we outline key priorities and future directions,including refining reconstruction methodologies,developing a comprehensive tree-ring-based avalanche database for high-altitude regions,and establishing an advanced hazard assessment framework based on dendrochronological evidence. 展开更多
关键词 DENDROGEOMORPHOLOGY Climate change Snow avalanche Reconstructed hazard assessment
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Influence of breach parameter models on hazard classification of off-stream reservoirs
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作者 Nathalia Silva-Cancino Fernando Salazar +1 位作者 Ernest Bladé Marcos Sanz-Ramos 《Water Science and Engineering》 2025年第1期102-114,共13页
The classification of dams or off-stream reservoirs concerning potential hazards in the event of failure often involves the use of two-dimensional hydraulic models for computing floodwave effects.These models necessit... The classification of dams or off-stream reservoirs concerning potential hazards in the event of failure often involves the use of two-dimensional hydraulic models for computing floodwave effects.These models necessitate defining breach geometry and formation time,for which various parametric models have been proposed.These models yield different values for average breach width,time of failure,and consequently,peak flows,as demonstrated by several researchers.This study analyzed the effect of selecting a breach parametric model on the hydraulic variables,potential damages,and hazard classification of structures.Three common parametric models were compared using a set of synthetic cases and a real off-stream reservoir.Results indicated significant effects of model choice.Material erodibility exerted a significant impact,surpassing that of failure mode.Other factors,such as the Manning coefficient,significantly affected the results.Utilizing an inadequate model or lacking information on dike material can lead to overly conservative or underestimated outcomes,thereby affecting hazard classification. 展开更多
关键词 Dam breach Off-stream reservoir hazard classification FLOODING Potential damages
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Identification and assessment of avalanche hazards in Aerxiangou section of Duku expressway in TianShan mountainous region based on unmanned aerial vehicle photography
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作者 QiuLian Cheng Jie Liu +3 位作者 Qiang Guo JiaHui Liu ZhiWei Yang ChangTao Hu 《Research in Cold and Arid Regions》 2025年第3期145-158,共14页
In this study,avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object,and 92 avalanches were accurately identified through onsite researc... In this study,avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object,and 92 avalanches were accurately identified through onsite research.A high-resolution three-dimensional model was established by collecting images from unmanned aerial vehicles for an in-depth understanding of the avalanche danger of the region,according to the sample set selection of different uses of machine learning support vector machines to establish the S1-RBFKSVM,S1-PKSVM,S2-RBFKSVM,and S2-PKSVM avalanche susceptibility coupling models.On the basis of the avalanche point susceptibility,the impact velocity,impact force,avalanche volume,and throw distance constitute the hazard evaluation system.The study results revealed that slopes in the range of 26.6°–46.9°are more prone to avalanches,and sample set 2 improved the accuracy by approximately 30%compared with sample set 1 trained in the avalanche susceptibility model.Principal component analysis revealed a total of 16 high-risk avalanches,which were distributed mainly on the southern side of the route.This study provides data support for avalanche simulations as well as early warning and prevention and provides theoretical and methodological guidance for the construction and operation of the Duku Expressway. 展开更多
关键词 AVALANCHE Support vector machine Principal component analysis hazard evaluation
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A general methodological framework for hazard assessment in remote mountain areas combining geomorphological mapping with UAV survey
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作者 Elena GAROVA Bogdan CHADROMTSEV +6 位作者 Alexander PEDANOV Pavel GREBENNIKOV Igor ILTUGANOV Pavel LOBANOV Pavel PONOMARJOVS Felix DRAESNER Sven FUCHS 《Journal of Mountain Science》 2025年第3期763-775,共13页
This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing... This paper presents a standardised workflow for conducting hazard assessments of mass wasting processes in remote mountain areas with limited data.The methodology integrates geomorphological mapping and remote sensing techniques and is adaptable to different national standards,thus ensuring its applicability in a variety of contexts.The principal objective is to guarantee the safety of mountainous regions,particularly in the vicinity of essential infrastructure,where the scope for implementing structural measures is restricted.The framework commences with comprehensive geomorphological mapping,which facilitates the identification of past hazardous processes and potential future hazards.New technologies,such as uncrewed aerial vehicles(UAVs),are employed to create high-resolution DEMs,which are particularly beneficial in regions with limited data availability.These models facilitate the assessment of potential hazards and inform decisions regarding protective measures.The utilisation of UAVs enhances the accuracy and efficiency of data collection,particularly in remote mountainous regions where alternative remotely sensed information may be unavailable.The integration of modern approaches into traditional hazard assessment methods allows for a comprehensive analysis of the spatial distribution of factors driving mass wasting processes.This workflow provides valuable insights that assist in the prioritisation of interventions and the optimisation of risk reduction in high mountainous areas. 展开更多
关键词 Geomorphological mapping hazard assessment UAV Remote mountain areas Mitigation planning
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Using the response surface method to conduct wave hazard assessment for a floating nuclear power plant
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作者 Shu-Wen Yu Xin-Yan Xu Chang-Hong Peng 《Nuclear Science and Techniques》 2025年第6期187-200,共14页
A floating nuclear power plant(FNPP)is an offshore facility that integrates proven light-water reactor technologies with floating platform characteristics.However,frequent contact with marine environments may lead to ... A floating nuclear power plant(FNPP)is an offshore facility that integrates proven light-water reactor technologies with floating platform characteristics.However,frequent contact with marine environments may lead to wave-induced vibrations and oscillations.This study aimed to evaluate the wave danger on FNPPs,which can negatively impact FNPP functionality.We developed a hydrodynamic model of an FNPP using potential flow theory and computed the frequency-domain fluid dynamic responses.After verifying the hydrodynamic model,we developed a predictive model for FNPP responses.This model utilizes a genetic aggregation methodology for batch prediction while ensuring accuracy.We analyzed all the wave data from a selected sea area over the past 50 years using the constructed surrogate model,enabling us to identify dangerous marine areas.By utilizing the extreme value distribution of important wave heights in these areas,we determined the wave return period,which poses a threat to FNPPs.This provides an important method for analyzing wave hazards to FNPPs. 展开更多
关键词 Floating nuclear power plant Wave hazard Hydrodynamic model
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Re-evaluation of an operating hazardous landfill site considering the conflict with neighboring inhabitants by multi-criteria decision
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作者 AYDI Abdelwaheb AQIL Tariq +1 位作者 SIFI Sinda ALZAHRANI Hassan 《Journal of Mountain Science》 2025年第3期1001-1014,共14页
Judicious selection of landfill allocation is crucial since inappropriate dumping of wastes can negatively impact human health and degrade the ecosystem.Therefore,this survey presents an integration multi-criteria dec... Judicious selection of landfill allocation is crucial since inappropriate dumping of wastes can negatively impact human health and degrade the ecosystem.Therefore,this survey presents an integration multi-criteria decision approach with the geographic information system for re-evaluating the pending hazardous landfill in Jradou,Tunisia,considering the conflict with neighboring inhabitants.The study involved twelve constraints and eight factors relevant to environmental and socio-economic challenges based on international works,guidelines of the country’s legislation,and an assessment questionnaire on the landfill suitability map.The Analytic Hierarchy Process(AHP)apportioned weights to criteria,and a Weighted Linear Combination(WLC)approach generated landfill suitability maps(LSM).Afterward,the produced LSM revealed that 2%(8.46km²)of the land was classified as very high,followed by 48%(203.04km²)as high,25%(105.75km²)as moderate,10%(42.3km²)as low,and the remaining 15%(63.45km²)as very low suitable.Furthermore,the operating hazardous waste landfill of Jradou falls within unsuitable areas,inflicting severe harm on the neighboring.The pending hazardous landfill of Jradou should be closed,and a new site must be identified.Conversely,the highly suitable classes are further identified in(1)the Eastern part of the study area,near Ouled ben Amara,and(2)the Northern part of Zaghouan,at 2 km north of Smenja,for potential future hazardous waste landfills.Consequently,governments and relevant stakeholders should investigate these zones to locate new landfills. 展开更多
关键词 hazardous waste LANDFILLING Multi-criteria decision approach Weighted Linear Combination
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Hazard Analysis of Dam Corridor Cracks Based on Field Detection and Numerical Calculation
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作者 Jiacheng Li Liangkun Gong +3 位作者 Yuxiang Li Jialiang Qian Weiyu Wu Weiran Lu 《Journal of World Architecture》 2025年第1期32-39,共8页
The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three... The longitudinal cracks distributed along the dam axis in the corridor of a dam may have potential safety hazards.According to the detection results of crack depth and width and the analysis of monitoring data,a three-dimensional finite element model is established for numerical simulation calculation and the influence of cracks on the safety of dam structure is analyzed from different aspects such as deformation,stress value,and distribution range.The calculation results show that the maximum principal tensile stress value and the location of the dam body are basically independent of the change of crack depth(within 1.0 m).Regarding local stress around the corridor,the high upstream water level causes cracks to deepen,resulting in an increase in the maximum tensile stress near the crack tip and an expansion of the tensile stress region. 展开更多
关键词 Gallery cracks Field test Finite element calculation hazard analysis
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Long-Term Environmental and Human Health Impacts of Hazardous Waste Incineration: A Case-Study in Catalonia, Spain
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作者 Jose L Domingo Joaquim Rovira Marta Schuchmacher 《Journal of Environmental & Earth Sciences》 2025年第6期227-243,共17页
This comprehensive review synthesizes findings from the studies conducted for more than two decades to assess en-vironmental and human health impacts near Spain's first hazardous waste incinerator(HWI)located in C... This comprehensive review synthesizes findings from the studies conducted for more than two decades to assess en-vironmental and human health impacts near Spain's first hazardous waste incinerator(HWI)located in Constantí(Tarra-gona,Catalonia).Through integrated analysis of polychlorinated dibenzo-p-dioxins/furans(PCDD/Fs)and metals across soil,vegetation,human tissues,and dietary matrices,the studies have shown:(1)PCDD/F concentrations decreased 75-96%in biological samples and dietary intake over 20 years,aligning with global emission reductions rather than HWI-4 operations;(2)metal trajectories showed arsenic intermittently exceeding carcinogenic thresholds in soils(1.1×10^(-4) risk index)and chromium accumulating in autopsy tissues(+16% in kidney),although without HWI-specific spatial gradi-ents;(3)systemic biomarkers revealed policy-driven declines—blood lead dropped 70% post-EU regulations,while mer-cury became undetectable in tissues post-2010.Health risk assessments confirmed that PCDD/F intake(0.122 pg WHO-TEQ/kg/day)remained still below WHO thresholds,with no attributable cancer risks for metals except legacy arsenic.The studies included in the program of surveillance show that PCDD/Fs and metals emissions by the HWI have meant a rather low contribution to population exposure to metals and PCDD/Fs compared to dietary and historical sources.How-ever,residual risks warrant attention.It mainly concerns chromium speciation and arsenic in soils,as well as the effects on vulnerable subpopulations and the synergistic effects among toxicants.Epidemiological studies are also required. 展开更多
关键词 hazardous Waste Incineration BIOMONITORING DIOXINS Heavy Metals Environmental Health Risk Assessment
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Dynamic fragmentation analysis of potential rockfall hazards at Zixia hydropower dam,Qinghai-Tibet Plateau
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作者 Maolin Wu Gang Luo +3 位作者 Xiewen Hu Yuzhang Bi Yufeng Wang Ning Ma 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4109-4123,共15页
The fragile and intricate geological environment of the Qinghai-Tibet Plateau gives rise to numerous precarious rocks along the riverbanks,posing significant risks for the upcoming construction of hydropower stations.... The fragile and intricate geological environment of the Qinghai-Tibet Plateau gives rise to numerous precarious rocks along the riverbanks,posing significant risks for the upcoming construction of hydropower stations.In order to identify potential rockfalls that could endanger the Zixia hydropower project,a comprehensive analysis employing various methods was conducted to investigate the kinematic characteristics and dynamic fragmentation of such precarious rocks.Initially,UAV oblique photography and field survey were used to create a digital elevation model with a resolution of 0.25 m and map the spatial distribution of precarious rocks.Subsequently,the development characteristics of joints within rock masses were analyzed through an adit investigation.Following these preliminary steps,a transportation simulation utilizing RocPro3D,considering stochastic initiation orientation,was employed to predict the trajectories of 18 precarious rocks.As a result,two hazardous rocks that pose a direct threat to the cofferdam were identified.Finally,considering the influence of internal structure planes,a discrete element method was applied for accurately simulating the kinematic characteristics and dynamic fragmentation of these hazardous rocks.The findings underscore several key observations:(1)Slopeparallel structure planes within these hazardous rocks play a pivotal role in both the progressive failure during initiation and dynamic fragmentation during transportation;(2)Hazardous rocksⅢ-1 andⅣ-1 would pose a direct threat to the cofferdam.Notably,block b4 from hazardous rockⅢ-1,could potentially impact the cofferdam with an energy of 4598.65 kJ and an impact force of 3007.5 kN;and(3)Continuous collisions encountered during transportation facilitate the disintegration of rock masses along structure planes and generate substantial high-velocity fragments.Finally,to cope with the impact risk of collapsing blocks,a reinforced retaining wall as the mitigation measure is recommended. 展开更多
关键词 Rockfall hazard identification Rockfall trajectory Numerical simulation Progressive failure Dynamic fragmentation
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Physically based deterministic rockfall hazard assessment integrating multi-failure modes at large scale:A case study of Tiefeng Township,Chongqing,China
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作者 Juan Du Xiao Feng +2 位作者 Bo Chai Kunlong Yin Li Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6324-6343,共20页
The rise in construction activities within mountainous regions has significantly increased the frequency of rockfalls.Statistical models for rockfall hazard assessment often struggle to achieve high precision on a lar... The rise in construction activities within mountainous regions has significantly increased the frequency of rockfalls.Statistical models for rockfall hazard assessment often struggle to achieve high precision on a large scale.This limitation arises primarily from the scarcity of historical rockfall data and the inadequacy of conventional assessment indicators in capturing the physical and structural characteristics of rockfalls.This study proposes a physically based deterministic model designed to accurately quantify rockfall hazards at a large scale.The model accounts for multiple rockfall failure modes and incorporates the key physical and structural parameters of the rock mass.Rockfall hazard is defined as the product of three factors:the rockfall failure probability,the probability of reaching a specific position,and the corresponding impact intensity.The failure probability includes probabilities of formation and instability of rock blocks under different failure modes,modeled based on the combination patterns of slope surfaces and rock discontinuities.The Monte Carlo method is employed to account for the randomness of mechanical and geometric parameters when quantifying instability probabilities.Additionally,the rock trajectories and impact energies simulated using Flow-R software are combined with rockfall failure probability to enable regional rockfall hazard zoning.A case study was conducted in Tiefeng,Chongqing,China,considering four types of rockfall failure modes.Hazard zoning results identified the steep and elevated terrains of the northern and southern anaclinal slopes as areas of highest rockfall hazard.These findings align with observed conditions,providing detailed hazard zoning and validating the effectiveness and potential of the proposed model. 展开更多
关键词 Rockfall hazard assessment Physically based deterministic model Multi-failure modes Large-scale data
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Research on the Construction of Immersive Education Systems for Fire Safety in University Laboratories Using VR/AR in Hazardous Chemical Scenarios
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作者 Xuezheng Wu 《Journal of Contemporary Educational Research》 2025年第10期357-362,共6页
With the rapid development of virtual reality(VR)and augmented reality(AR)technologies,their application potential in the field of education has become increasingly significant.For a long time,fire safety education in... With the rapid development of virtual reality(VR)and augmented reality(AR)technologies,their application potential in the field of education has become increasingly significant.For a long time,fire safety education in university laboratories has faced numerous challenges,and traditional teaching methods have been insufficiently effective,with high-risk scenarios difficult to realistically recreate.Especially in special scenarios involving hazardous chemicals,conventional training methods struggle to enable learners to achieve deep understanding and behavioral formation.This study systematically integrates immersive technology theory with safety education needs,providing a replicable technical solution for safety education in high-risk environments.Its modular design approach has reference value for expansion into other professional fields,offering practical evidence for innovation in safety education models in the digital age. 展开更多
关键词 VR/AR hazardous chemicals scenarios University laboratories Fire safety Immersive education
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Functional evidential reasoning model(FERM)-A new systematic approach for exploring hazardous chemical operational accidents under uncertainty
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作者 Qianlin Wang Jiaqi Han +6 位作者 Lei Cheng Feng Wang Yiming Chen Zhan Dou Bing Zhang Feng Chen Guoan Yang 《Chinese Journal of Chemical Engineering》 2025年第5期255-269,共15页
This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal... This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal factors and their performance changes in hazardous chemical operational accidents, along with determining the functional failure link relationships. Subsequently, FERM was employed to elucidate both qualitative and quantitative operational accident information within a unified framework, which could be regarded as the input of information fusion to obtain the fuzzy belief distribution of each cause factor. Finally, the derived risk values of the causal factors were ranked while constructing multi-level accident causation chains to unveil the weak links in system functionality and the primary roots of operational accidents. Using the specific case of the “1·15” major explosion and fire accident at Liaoning Panjin Haoye Chemical Co., Ltd., seven causal factors and their corresponding performance changes were identified. Additionally, five accident causation chains were uncovered based on the fuzzy joint distribution of the functional assessment level(FAL) and reliability distribution(RD),revealing an overall increase in risk along the accident evolution path. The research findings demonstrated that FERM enabled the effective characterization, rational quantification and accurate analysis of the inherent uncertainties in hazardous chemical operational accident risks from a systemic perspective. 展开更多
关键词 Functional evidential reasoning model (FERM) Accident causation analysis Operational accidents hazardous chemical UNCERTAINTY
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A Self‐Powered,Shapeable,and Wearable Sensor for Effective Hazard Prevention and Biomechanical Monitoring
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作者 Huimin Wang Shuo Li +5 位作者 Yong Zhang Mingchao Zhang Haomin Wang Xiaoping Liang Haojie Lu Yingying Zhang 《SmartSys》 2025年第1期30-38,共9页
Flexible and wearable electronics are attracting surging attention due to their potential applications in human health monitoring and precision therapies.Safety hazards including strong magnetic field and electric lea... Flexible and wearable electronics are attracting surging attention due to their potential applications in human health monitoring and precision therapies.Safety hazards including strong magnetic field and electric leakage are big risk factors for human health.It remains challenging to develop self‐powered and wearable safety hazard sensors that could not only be able to monitor human motions but also have functions for detecting potential hazards.In this work,we fabricated a self‐powered,shapeable,and wearable magnetic triboelectric nanogenerator(MTENG)based on ferrofluid,Ecoflex,and carbonized silk fabric that possessed effective hazard prevention and biomechanical motion sensing ability.A peak open‐circuit voltage of 0.7 V and short‐circuit current of 10μA m^(−2)can be achieved when magnetic field is changed between 3.5 and 37.1 mT.As a component of triboelectric layer of the MTENG,ferrofluid can substantially extend the range of its sensing capabilities to many hazardous cues such as dangerous magnetic field.Furtherly,the developed multifunctional and self‐powered sensor can be used to monitor human activities such as drinking water and bending finger.This effort opens up a new design opportunity for hazard avoidance wearable electronics and self‐powered sensors. 展开更多
关键词 biomechanical monitoring hazard prevention magnetically induced triboelectric nanogenerator self‐powered wearable sensor
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The enrichment of hazardous elements, rare earth elements and other inorganic constituents in a thick coal seam of the Lower Indus Basin, Pakistan
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作者 Hassan Nasir Mangi Liqiang Ma +4 位作者 Robert B.Finkelman Detian Yan Jing Li Lara Sindhu Umar Ashraf 《International Journal of Coal Science & Technology》 2025年第3期291-312,共22页
The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objecti... The presence of inorganic constituents in coal is controlled by different geological factors,which,in turn,affect the technological,environmental,and health impacts of the coal.The main aim of this study is to objectively assess the mineralogical and geochemical characteristics of a thickest low-rank coal seam in the Lower Indus Basin southeastern Pakistan,and further investigate different controlling factors.The analytical results of major oxides,trace elements,and rare earth elements revealed that the weathering conditions were progressively variable and moderate.The sediment source,mainly of felsic and intermediate composition,was dominated by granitic rocks.The geochemical assessment reveals different depositional factors like marine environment influenced,while transitional and freshwater sediments influenced the center of the coal peat mire.Strontium,Zinc,and several hazardous trace elements,including Cu,Ni,Cr,and Co,have higher concentrations in these coals compared to world low-rank,U.S.,and Chinese coals.The relatively higher concentration of Sr in the thick coal seam in the Lower Indus Basin,compared to other coals seams in Pakistan and the enrichment of Sr was primarily controlled by the denudation of crystalline rocks and marine influx in the coal-basin.The REY distribution pattern showed that enrichment of medium and heavy rare earth elements is higher than light rare earth elements in the coal seam.The Gd distribution pattern in the coal seam demonstrated that strong positive anomalies had a good affinity with paleo-acidic water concentration in the study area.The higher concentration of Sr and other elements enables a better assessment understanding of the coal geochemical history. 展开更多
关键词 Coal geochemical analysis Trace elements STRONTIUM hazardous elements Rare earth elements Lower-Indus Basin
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