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基于24Model-D-ISM的地铁站火灾疏散影响因素研究
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作者 孙世梅 张家严 《中国安全科学学报》 CAS CSCD 北大核心 2024年第4期153-159,共7页
为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾... 为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾人员疏散影响因素指标体系;采用算子客观赋权法(C-OWA)改进决策试验与评价实验法(DEMATEL),确定地铁站火灾人员疏散的重要影响因素;在此基础上,采用解释结构模型(ISM)分析各个因素间的层次结构及相互作用路径,构建地铁站火灾人员疏散影响因素的多级递阶结构模型。研究结果表明:疏散引导、恐慌从众行为、人员拥挤为地铁站火灾人员疏散的关键影响因素;地铁站火灾人员疏散受表层因素、中间层因素、深层因素共同作用的影响,其中,疏散教育与培训、设施维护与检查、疏散预案等因素是根源影响因素,重视根源影响因素的改善有利于从本质上预防和控制事故的发生。 展开更多
关键词 2-4”模型(24model) 决策试验与评价实验法(DEMATEL) 解释结构模型(ISM) 地铁站 火灾疏散 影响因素
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24Model与LCM原因因素定义对比研究 被引量:2
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作者 袁晨辉 傅贵 +1 位作者 吴治蓉 赵金坤 《中国安全科学学报》 CAS CSCD 北大核心 2024年第1期27-34,共8页
为探究损失致因模型(LCM)原因因素定义与事故致因“2-4”模型(24Model)存在的异同和优缺点,梳理2个模型各层面原因和结果的定义,对比定义内容及其对事故原因分析等安全实务的指导作用,并以一起瓦斯爆炸事故为例加以实证分析,获得二者分... 为探究损失致因模型(LCM)原因因素定义与事故致因“2-4”模型(24Model)存在的异同和优缺点,梳理2个模型各层面原因和结果的定义,对比定义内容及其对事故原因分析等安全实务的指导作用,并以一起瓦斯爆炸事故为例加以实证分析,获得二者分析结果之间的差异。研究结果表明:LCM是首个将管理因素纳入事故致因分析的一维事件序列模型,可明确各层面原因因素的定义和因素间的逻辑关系,但部分定义存在交叉重复的问题,并没有揭示安全工作指导思想等深层次事故致因因素;24Model作为系统性事故致因模型,对各类因素的定义均以组织为主体,描述事件、事故、安全的概念内涵,划分个体安全动作、安全能力和组织安全管理体系的类别并给出含义解析,探究组织安全文化层面的问题并以32个元素体现;2个模型的事故原因分析方法均建立在对各层级原因因素定义的基础上,并适用于模型理论体系本身。 展开更多
关键词 2-4”模型(24model) 损失致因模型(LCM) 事故致因模型 原因因素定义 对比研究
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内皮细胞特异性骨形态发生蛋白2对血管新生的影响:生物信息学分析和实验验证
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作者 燕茹 王凯茹 +2 位作者 张飞燕 贾绍斌 丛广志 《中国组织工程研究》 CAS 北大核心 2025年第1期103-110,共8页
背景:血管新生是心血管疾病的主要干预靶点,骨形态发生蛋白2具有调控血管新生作用,但内皮细胞特异性骨形态发生蛋白2对血管新生的调控作用不清楚。目的:探讨内皮细胞特异性骨形态发生蛋白2对血管新生的影响。方法:(1)生物信息学分析:通... 背景:血管新生是心血管疾病的主要干预靶点,骨形态发生蛋白2具有调控血管新生作用,但内皮细胞特异性骨形态发生蛋白2对血管新生的调控作用不清楚。目的:探讨内皮细胞特异性骨形态发生蛋白2对血管新生的影响。方法:(1)生物信息学分析:通过Panglao DB公共基因表达数据库单细胞转录组荟萃分析观察骨形态发生蛋白2细胞群表达丰度和定位。血管新生小鼠和内皮(心内膜)过表达骨形态发生蛋白2小鼠转录组测序数据集探索内皮细胞骨形态发生蛋白2对血管新生信号通路的调控作用。(2)体内实验验证:建立小鼠后肢缺血模型,对比模型小鼠患侧与健侧缺血后肢7,14和21 d血流灌注情况,免疫荧光和免疫组织化学染色评估小鼠骨形态发生蛋白2和CD31的表达定位情况。(3)体外实验验证:体外培养人脐静脉内皮细胞,分为对照组、缺氧组和骨形态发生蛋白2抑制剂(Noggin蛋白)干预组,培养24 h,观察各组内皮细胞血管新生情况。结果与结论:(1)内皮细胞是表达骨形态发生蛋白2的重要细胞亚群,在血管新生内皮细胞和骨形态发生蛋白2过表达内皮细胞转录组再分析均发现骨形态发生蛋白2表达明显升高,血管新生通路明显激活。(2)缺血7 d小鼠新生血管周围骨形态发生蛋白2阳性血管明显增加(P<0.05),缺血2周骨形态发生蛋白2阳性血管明显减少(P<0.001)。(3)体外培养人脐静脉内皮细胞,缺氧干预后,内皮细胞迁移能力和血管出芽明显增加,血管新生因子血管内皮生长因子和血小板衍生生长因子的表达明显升高,Noggin明显减少了缺氧诱导的内皮细胞血管新生(P<0.001),并下调血管内皮生长因子和血小板衍生生长因子的表达(P<0.01)。(4)结果证实,内皮细胞特异性骨形态发生蛋白2具有调控血管新生作用,靶向性内皮细胞骨形态发生蛋白2可望改善血管新生。 展开更多
关键词 内皮细胞 骨形态发生蛋白2 血管新生 单细胞RNA测序 批量RNA测序 信号通路 后肢缺血模型 成管实验
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The Flexible Global Ocean-Atmosphere-Land System Model, Grid-point Version 2: FGOALS-g2 被引量:40
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作者 李立娟 林鹏飞 +27 位作者 俞永强 王斌 周天军 刘利 刘骥平 包庆 徐世明 黄文誉 夏坤 普业 董理 申思 刘屹岷 胡宁 刘咪咪 孙文奇 史湘军 郑伟鹏 吴波 宋米荣 刘海龙 张学洪 吴国雄 薛巍 黄小猛 杨广文 宋振亚 乔方利 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期543-560,共18页
This study mainly introduces the development of the Flexible Global Ocean-Atmosphere-Land System Model: Grid-point Version 2 (FGOALS-g2) and the preliminary evaluations of its performances based on re- sults from t... This study mainly introduces the development of the Flexible Global Ocean-Atmosphere-Land System Model: Grid-point Version 2 (FGOALS-g2) and the preliminary evaluations of its performances based on re- sults from the pre-industrial control run and four members of historical runs according to the fifth phase of the Coupled Model Intercomparison Project (CMIP5) experiment design. The results suggest that many obvi- ous improvements have been achieved by the FGOALS-g2 compared with the previous version, FGOALS-gl, including its climatological mean states, climate variability, and 20th century surface temperature evolution. For example, FGOALS-g2 better simulates the frequency of tropical land precipitation, East Asian Monsoon precipitation and its seasonal cycle, MJO and ENSO, which are closely related to the updated cumulus parameterization scheme, as well as the alleviation of uncertainties in some key parameters in shallow and deep convection schemes, cloud fraction, cloud macro/microphysical processes and the boundary layer scheme in its atmospheric model. The annual cycle of sea surface temperature along the equator in the Pacific is significantly improved in the new version. The sea ice salinity simulation is one of the unique characteristics of FGOALS-g2, although it is somehow inconsistent with empirical observations in the Antarctic. 展开更多
关键词 fgoals-g2 climatological mean state climate variability 20th century climate MONSOON
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Oceanic Climatology in the Coupled Model FGOALS-g2: Improvements and Biases 被引量:4
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作者 林鹏飞 俞永强 刘海龙 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第3期819-840,共22页
The present study examines simulated oceanic climatology in the Flexible Global Ocean-Atmosphere- Land System model, Grid-point Version 2 (FGOALS-g2) forced by historical external forcing data. The oceanic temperatu... The present study examines simulated oceanic climatology in the Flexible Global Ocean-Atmosphere- Land System model, Grid-point Version 2 (FGOALS-g2) forced by historical external forcing data. The oceanic temperatures and circulations in FGOALS-g2 were found to be comparable to those observed, and substantially improved compared to those simulated by the previous version, FGOALS-gl.0. Compared with simulations by FGOALS-gl.0, the shallow mixed layer depths were better captured in the eastern Atlantic and Pacific Ocean in FGOALS-g2. In the high latitudes of the Northern Hemisphere, the cold biases of SST were about 1℃-5℃ smaller in FGOALS-g2. The associated sea ice distributions and their seasonal cycles were more realistic in FGOALS-g2. The pattern of Atlantic Meridional Overturning Circulation (AMOC) was better simulated in FGOALS-g2, although its magnitude was larger than that found in observed data. The simulated Antarctic Circumpolar Current (ACC) transport was about 140 Sv through the Drake Passage, which is close to that observed. Moreover, Antarctic Intermediate Water (AAIW) was better captured in FGOALS-g2. However, large SST cold biases (〉3℃) were still found to exist around major western boundary currents and in the Barents Sea, which can be explained by excessively strong oceanic cold advection and unresolved processes owing to the coarse resolution. In the Indo-Pacific warm pool, the cold biases were partly related to the excessive loss of heat from the ocean. Along the eastern coast in the Atlantic and Pacific Oceans, the warm biases were due to overestimation of shortwave radiation. In the Indian Ocean and Southern Ocean, the surface fresh biases were mainly due to the biases of precipitation. In the tropical Pacific Ocean, the surface fresh biases (〉2 psu) were mainly caused by excessive precipitation and oceanic advection. In the Indo-Pacific Ocean, fresh biases were also found to dominate in the upper 1000 m, except in the northeastern Indian Ocean. There were warm and salty biases (3℃-4℃ and 1-2 psu) from the surface to the bottom in the Labrador Sea, which might be due to large amounts of heat transport and excessive evaporation, respectively. For vertical structures, the maximal biases of temperature and salinity were found to be located at depths of 〉600 m in the Arctic Ocean, and their values exceeded 4℃ and 2 psu, respectively. 展开更多
关键词 fgoals-g2 oceanic climatology temperature salinity ocean circulation
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An Assessment of Indo-Pacific Oceanic Channel Dynamics in the FGOALS-g2 Coupled Climate System Model 被引量:4
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作者 徐腾飞 袁东亮 +1 位作者 俞永强 赵霞 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2013年第4期997-1016,共20页
Lag correlations of sea surface temperature anomalies (SSTAs), sea surface height anomalies (SSHAs), subsurface temperature anomalies, and surface zonal wind anomalies (SZWAs) produced by the Flexible Global Oce... Lag correlations of sea surface temperature anomalies (SSTAs), sea surface height anomalies (SSHAs), subsurface temperature anomalies, and surface zonal wind anomalies (SZWAs) produced by the Flexible Global Ocean-Atmosphere-Land System modeh Grid-point Version 2 (FGOALS-g2) are analyzed and com- pared with observations. The insignificant, albeit positive, lag correlations between the SSTAs in the south- eastern tropical Indian Ocean (STIO) in fall and the SSTAs in the central-eastern Pacific cold tongue in the following summer through fall are found to be not in agreement with the observational analysis. The model, however, does reproduce the significant lag correlations between tile SSHAs in the STIO in fall and those in the cold tongue at the one-year time lag in the observations. These, along with the significant lag correlations between the SSTAs in the STIO in fall and the subsurface temperature anomalies in the equatorial Pacific vertical section in the following year, suggest that the Indonesian Throughflow plays an important role in propagating the Indian Ocean anomalies into the equatorial Pacific Ocean. Analyses of the interannual anomalies of the Indonesian Throughflow transport suggest that the FGOALS-g2 climate system simulates, but underestimates, the oceanic channel dynamics between the Indian and Pacific Oceans. FGOALS-g2 is shown to produce lag correlations between the SZWAs over the western equatorial Pacific in fall and the cold tongue SSTAs at the one-year time lag that are too strong to be realistic in comparison with observations. The analyses suggest that the atmospheric bridge over the Indo-Pacific Ocean is overestimated in the FGOALS-g2 coupled climate model. 展开更多
关键词 Indian Ocean Dipole ENSO oceanic channel fgoals-g2 Indonesian Throughflow
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Phosphorus limitation on CO_(2)fertilization effect in tropical forests informed by a coupled biogeochemical model
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作者 Zhuonan Wang Hanqin Tian +5 位作者 Shufen Pan Hao Shi Jia Yang Naishen Liang Latif Kalin Christopher Anderson 《Forest Ecosystems》 SCIE CSCD 2024年第4期502-515,共14页
Tropical forests store more than half of the world's terrestrial carbon(C)pool and account for one-third of global net primary productivity(NPP).Many terrestrial biosphere models(TBMs)estimate increased productivi... Tropical forests store more than half of the world's terrestrial carbon(C)pool and account for one-third of global net primary productivity(NPP).Many terrestrial biosphere models(TBMs)estimate increased productivity in tropical forests throughout the 21st century due to CO_(2)fertilization.However,phosphorus(P)liaitations on vegetation photosynthesis and productivity could significantly reduce the CO_(2)fertilization effect.Here,we used a carbon-nitrogen-phosphorus coupled model(Dynamic Land Ecosystem Model;DLEM-CNP)with heterogeneous maximum carboxylation rates to examine how P limitation has affected C fluxes in tropical forests during1860-2018.Our model results showed that the inclusion of the P processes enhanced model performance in simulating ecosystem productivity.We further compared the simulations from DLEM-CNP,DLEM-CN,and DLEMC and the results showed that the inclusion of P processes reduced the CO_(2)fertilization effect on gross primary production(GPP)by 25%and 45%,and net ecosystem production(NEP)by 28%and 41%,respectively,relative to CN-only and C-on ly models.From the 1860s to the 2010s,the DLEM-CNP estimated that in tropical forests GPP increased by 17%,plant respiration(Ra)increased by 18%,ecosystem respiration(Rh)increased by 13%,NEP increased by 121%per unit area,respectively.Additionally,factorial experiments with DLEM-CNP showed that the enhanced NPP benefiting from the CO_(2) fertilization effect had been offset by 135%due to deforestation from the 1860s to the 2010s.Our study highlights the importance of P limitation on the C cycle and the weakened CO_(2)fertilization effect resulting from P limitation in tropical forests. 展开更多
关键词 Tropical forests Carbon-nitrogen-phosphorus model Phosphorus limitation CO_(2)fertilization effect Terrestfial ecosy stem model
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Reduction of uncertainties in rice yield response to elevated CO_(2) by experiment-model integration:A case study in East China
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作者 Zihao Wang Yu Zhang +2 位作者 Xueni Wang Yanfeng Ding Songhan Wang 《The Crop Journal》 SCIE CSCD 2024年第6期1812-1816,共5页
Accurate prediction of future rice yield needs the precise estimations of rice yield response to climate change factors,of which the most important one is the increasing carbon dioxide(CO_(2))concentrations.Estimates ... Accurate prediction of future rice yield needs the precise estimations of rice yield response to climate change factors,of which the most important one is the increasing carbon dioxide(CO_(2))concentrations.Estimates of CO_(2) fertilization effect(CFE)on rice,however,still had large uncertainties.Therefore,using the rice planting areas in East China as the study area,we firstly compared the rice yields and CFE predicted by four state-of-the-art crop models,and found that the CFE predicted by these models had significant differences.We then quantified the CFE on rice yield using the field-controlled experiment conducted at Danyang site at Jiangsu province.Using CFE measurements from a field experiment as benchmark,we have developed an experiment–model integration approach aiming to reduce this variation.This study thus highlights the large CFE uncertainties of current crop models and provides us with a method to reduce this uncertainty,which is beneficial for the accurate prediction of future global rice yield in the context of climate change. 展开更多
关键词 Rice yield Elevated CO_(2) Experiment-model integration Field experiment Crop models
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Performance validation of High Mountain Asia 8-meter Digital Elevation Model using ICESat-2 geolocated photons
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作者 Giribabu DANDABATHULA Subham ROY +7 位作者 Omkar Shashikant GHATAGE Vaibhav Balaso KOLASE Shwetambari SATPUTE Koushik GHOSH Sahibnoor KAUR Satyanarayana PONDARI Apurba Kumar BERA Sushil Kumar SRIVASTAV 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2562-2578,共17页
High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to ana... High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to analyze it in a 3D environment and understand its intricate role as the Water Tower of Asia.The science teams of NASA realized an 8-m DEM using satellite stereo imagery for HMA,termed HMA 8-m DEM.In this research,we assessed the vertical accuracy of HMA 8-m DEM using reference elevations from ICESat-2 geolocated photons at three test sites of varied topography and land covers.Inferences were made from statistical quantifiers and elevation profiles.For the world’s highest mountain,Mount Everest,and its surroundings,Root Mean Squared Error(RMSE)and Mean Absolute Error(MAE)resulted in 1.94 m and 1.66 m,respectively;however,a uniform positive bias observed in the elevation profiles indicates the seasonal snow cover change will dent the accurate estimation of the elevation in this sort of test sites.The second test site containing gentle slopes with forest patches has exhibited the Digital Surface Model(DSM)features with RMSE and MAE of 0.58 m and 0.52 m,respectively.The third test site,situated in the Zanda County of the Qinghai-Tibet,is a relatively flat terrain bed,mostly bare earth with sudden river cuts,and has minimal errors with RMSE and MAE of 0.32 m and 0.29 m,respectively,and with a negligible bias.Additionally,in one more test site,the feasibility of detecting the glacial lakes was tested,which resulted in exhibiting a flat surface over the surface of the lakes,indicating the potential of HMA 8-m DEM for deriving the hydrological parameters.The results accrued in this investigation confirm that the HMA 8-m DEM has the best vertical accuracy and should be of high use for analyzing natural hazards and monitoring glacier surfaces. 展开更多
关键词 High Mountain Asia Digital Elevation model ICESat-2 geolocated photons Accuracy assessment
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A multi-mechanism numerical simulation model for CO_(2)-EOR and storage in fractured shale oil reservoirs
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作者 Yuan-Zheng Wang Ren-Yi Cao +3 位作者 Zhi-Hao Jia Bin-Yu Wang Ming Ma Lin-Song Cheng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1814-1828,共15页
Under the policy background and advocacy of carbon capture,utilization,and storage(CCUS),CO_(2)-EOR has become a promising direction in the shale oil reservoir industry.The multi-scale pore structure distribution and ... Under the policy background and advocacy of carbon capture,utilization,and storage(CCUS),CO_(2)-EOR has become a promising direction in the shale oil reservoir industry.The multi-scale pore structure distribution and fracture structure lead to complex multiphase flow,comprehensively considering multiple mechanisms is crucial for development and CO_(2) storage in fractured shale reservoirs.In this paper,a multi-mechanism coupled model is developed by MATLAB.Compared to the traditional Eclipse300 and MATLAB Reservoir Simulation Toolbox(MRST),this model considers the impact of pore structure on fluid phase behavior by the modified Peng—Robinson equation of state(PR-EOS),and the effect simultaneously radiate to Maxwell—Stefan(M—S)diffusion,stress sensitivity,the nano-confinement(NC)effect.Moreover,a modified embedded discrete fracture model(EDFM)is used to model the complex fractures,which optimizes connection types and half-transmissibility calculation approaches between non-neighboring connections(NNCs).The full implicit equation adopts the finite volume method(FVM)and Newton—Raphson iteration for discretization and solution.The model verification with the Eclipse300 and MRST is satisfactory.The results show that the interaction between the mechanisms significantly affects the production performance and storage characteristics.The effect of molecular diffusion may be overestimated in oil-dominated(liquid-dominated)shale reservoirs.The well spacing and injection gas rate are the most crucial factors affecting the production by sensitivity analysis.Moreover,the potential gas invasion risk is mentioned.This model provides a reliable theoretical basis for CO_(2)-EOR and sequestration in shale oil reservoirs. 展开更多
关键词 CO_(2)-EOR CO_(2)storage Shale oil reservoir Complex fracture model Multiple mechanisms
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3D seismic forward modeling from the multiphysical inversion at the Ketzin CO_(2) storage site
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作者 Yi-kang Zheng Chong Wang +2 位作者 Hao-hong Liang Yi-bo Wang Rong-shu Zeng 《Applied Geophysics》 SCIE CSCD 2024年第3期593-605,620,共14页
From June 2008 to August 2013,approximately 67 kt of CO_(2) was injected into a deep saline formation at the Ketzin pilot CO_(2) storage site.During injection,3D seismic surveys have been performed to monitor the migr... From June 2008 to August 2013,approximately 67 kt of CO_(2) was injected into a deep saline formation at the Ketzin pilot CO_(2) storage site.During injection,3D seismic surveys have been performed to monitor the migration of sequestered CO_(2).Seismic monitoring results are limited by the acquisition and signal-to-noise ratio of the acquired data.The multiphysical reservoir simulation provides information regarding the CO_(2) fluid behavior,and the approximated model should be calibrated with the monitoring results.In this work,property models are delivered from the multiphysical model during 3D repeated seismic surveys.The simulated seismic data based on the models are compared with the real data,and the results validate the effectiveness of the multiphysical inversion method.Time-lapse analysis shows the trend of CO_(2) migration during and after injection. 展开更多
关键词 Seismic forward modeling reservoir simulation CO_(2)storage time-lapse analysis
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Depositional model of the Member Deng-2 marginal microbial mound-bank complex of the Dengying Formation in the southwestern Sichuan Basin, SW China: Implications for the Ediacaran microbial mound construction and hydrocarbon exploration
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作者 Jin-Min Song Xin Jin +10 位作者 Zhong Luo Shu-Gen Liu Shao-Bo Liu Xing-Zhi Ma Zhi-Wu Li Xue-Song Lu Ling-Li Zhao Ke-Ran Li Jia-Xin Ren Li-Zhou Tian Hao-Shuang Deng 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期806-822,共17页
Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional p... Recent advances in hydrocarbon exploration have been made in the Member Deng-2 marginal microbial mound-bank complex reservoirs of the Dengying Formation in the western Sichuan Basin, SW China,where the depositional process is regarded confusing. The microfacies, construction types, and depositional model of the Member Deng-2 marginal microbial mound-bank complex have been investigated using unmanned aerial vehicle photography, outcrop section investigation, thin section identification,and seismic reflections in the southwestern Sichuan Basin. The microbialite lithologic textures in this region include thrombolite, dendrolite, stromatolite, fenestral stromatolite, spongiostromata stone,oncolite, aggregated grainstone, and botryoidal grapestone. Based on the comprehensive analysis of“depositional fabrics-lithology-microfacies”, an association between a fore mound, mound framework,and back mound subfacies has been proposed based on water depth, current direction, energy level and lithologic assemblages. The microfacies of the mound base, mound core, mound flank, mound cap, and mound flat could be recognized among the mound framework subfacies. Two construction types of marginal microbial mound-bank complex have been determined based on deposition location, mound scale, migration direction, and sedimentary facies association. Type Jinkouhe microbial mound constructions(TJMMCs) develop along the windward margin owing to their proximity to the seaward subfacies fore mound, with a northeastwardly migrated microbial mound on top of the mud mound,exhibiting the characteristics of large-sized mounds and small-sized banks in the surrounding area. Type E'bian microbial mound constructions(TEMMCs) primarily occur on the leeward margin, resulting from the presence of onshore back mound subfacies, with the smaller southwestward migrated microbial mounds existing on a thicker microbial flat. The platform margin microbial mound depositional model can be correlated with certain lateral comparison profile and seismic reflection structures in the 2D seismic section, which can provide references for future worldwide exploration. Microbial mounds with larger buildups and thicker vertical reservoirs are typically targeted on the windward margin, while small-sized microbial mounds and flats with better lateral connections are typically focused on the leeward margin. 展开更多
关键词 Sichuan Basin The Member Deng-2 Marginal microbial mound-bank complex Depositional model Exploration implications
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Numerical modeling of blast-induced rock fragmentation in deep mining with 3D and 2D FEM method approaches
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作者 Michał Kucewicz Mazurkiewicz Łukasz +4 位作者 Paweł Baranowski Jerzy Małachowski Krzysztof Fuławka Piotr Mertuszka Marcin Szumny 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第11期4532-4553,共22页
To optimize the excavation of rock using underground blasting techniques,a reliable and simplified approach for modeling rock fragmentation is desired.This paper presents a multistep experimentalnumerical methodology ... To optimize the excavation of rock using underground blasting techniques,a reliable and simplified approach for modeling rock fragmentation is desired.This paper presents a multistep experimentalnumerical methodology for simplifying the three-dimensional(3D)to two-dimensional(2D)quasiplane-strain problem and reducing computational costs by more than 100-fold.First,in situ tests were conducted involving single-hole and free-face blasting of a dolomite rock mass in a 1050-m-deep mine.The results were validated by laser scanning.The craters were then compared with four analytical models to calculate the radius of the crushing zone.Next,a full 3D model for single-hole blasting was prepared and validated by simulating the crack length and the radius of the crushing zone.Based on the stable crack propagation zones observed in the 3D model and experiments,a 2D model was prepared.The properties of the high explosive(HE)were slightly reduced to match the shape and number of radial cracks and crushing zone radius between the 3D and 2D models.The final methodology was used to reproduce various cut-hole blasting scenarios and observe the effects of residual cracks in the rock mass on further fragmentation.The presence of preexisting cracks was found to be crucial for fragmentation,particularly when the borehole was situated near a free rock face.Finally,an optimization study was performed to determine the possibility of losing rock continuity at different positions within the well in relation to the free rock face. 展开更多
关键词 Dolomite rock Two-dimensional(2D)rock modeling Rock fragmentation Cut-hole blasting
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Metal-N_(4) model single‐atom catalyst with electroneutral quadri‐pyridine macrocyclic ligand for CO_(2) electroreduction
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作者 Jian‐Zhao Peng Yin‐Long Li +7 位作者 Yao‐Ti Cheng Fu‐Zhi Li Bo Cao Qing Wang Xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期122-133,共12页
Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous electrocatalysis.Since metal sites with diverse local structures coexist in this type of ma... Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous electrocatalysis.Since metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to establish.Conjugated macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom catalysts.Metal–N_(4) site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been reported.In this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2) electroreduction.For comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also prepared.The Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic ligand.Constrained ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2). 展开更多
关键词 ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst
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Delayed treatment of diabetic foot ulcer in patients with type 2 diabetes and its prediction model
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作者 Hui Chen Ying Xi 《World Journal of Diabetes》 SCIE 2024年第10期2070-2080,共11页
BACKGROUND Diabetic foot(DF)is a serious complication of type 2 diabetes.This study aimed to investigate the factors associated with DF occurrence and the role of delayed medical care in a cohort of patients with type... BACKGROUND Diabetic foot(DF)is a serious complication of type 2 diabetes.This study aimed to investigate the factors associated with DF occurrence and the role of delayed medical care in a cohort of patients with type 2 diabetes.AIM To reveal the impact of delayed medical treatment on the development of DF in patients with type 2 diabetes and to establish a predictive model for DF.METHODS In this retrospective cohort study,292 patients with type 2 diabetes who underwent examination at our hospital from January 2023 to December 2023 were selected and divided into the DF group(n=82,DF)and nondiabetic foot group(n=210,NDF).Differential and correlation analyses of demographic indicators,laboratory parameters,and delayed medical treatment were conducted for the two groups.Logistic regression was applied to determine influencing factors.Receiver operating characteristic(ROC)analysis was performed,and indicators with good predictive value were selected to establish a combined predictive model.RESULTS The DF group had significantly higher body mass index(BMI)(P<0.001),disease duration(P=0.012),plasma glucose levels(P<0.001),and HbA1c(P<0.001)than the NDF group.The NDF group had significantly higher Acute Thrombosis and Myocardial Infarction Health Service System(ATMHSS)scores(P<0.001)and a significantly lower delayed medical treatment rate(72.38%vs 13.41%,P<0.001).BMI,duration of diabetes,plasma glucose levels,HbA1c,diabetic peripheral neuropathy,and nephropathy were all positively correlated with DF occurrence.ATMHSS scores were negatively correlated with delayed time to seek medical treatment.The logistic regression model revealed that BMI,duration of diabetes,plasma glucose levels,HbA1c,presence of diabetic peripheral neuropathy and nephropathy,ATMHSS scores,and delayed time to seek medical treatment were influencing factors for DF.ROC analysis indicated that plasma glucose levels,HbA1c,and delayed medical treatment had good predictive value with an area under the curve of 0.933 for the combined predictive model.CONCLUSION Delayed medical treatment significantly affects the probability of DF occurrence in patients with diabetes.Plasma glucose levels,HbA1c levels,and the combined predictive model of delayed medical treatment demonstrate good predictive value. 展开更多
关键词 Delayed treatment Medical attention Diabetic foot ulcer Type 2 diabetes Prediction model
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Study of the Effect of High-Voltage Low-Frequency Electrotherapy on Type 2 Diabetes in an in Vivo Model
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作者 Vladimir Kriman 《Journal of Biosciences and Medicines》 2024年第11期213-220,共8页
The study investigates the impact of high-voltage low-frequency electrotherapy on glucose levels and hematological parameters in an in vivo model of type 2 diabetes. The results demonstrate a significant reduction in ... The study investigates the impact of high-voltage low-frequency electrotherapy on glucose levels and hematological parameters in an in vivo model of type 2 diabetes. The results demonstrate a significant reduction in glucose increases during glucose tolerance tests (GTT) and suggest potential mechanisms, including improved insulin sensitivity and reduced inflammation. Hematological analysis indicates no adverse effects of electrotherapy on healthy or diabetic mice. This study supports the potential of high-voltage low-frequency electrotherapy as an adjunctive treatment for type 2 diabetes, warranting further research into its mechanisms and long-term effects. 展开更多
关键词 Type 2 Diabetes In Vivo model High-Voltage Electrotherapy Glucose Tolerance Test (GTT) Hematological Analysis
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Prediction of(n,2n)reaction cross-sections of long-lived fission products based on tensor model
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作者 Jia-Li Huang Hui Wang +7 位作者 Ying-Ge Huang Er-Xi Xiao Yu-Jie Feng Xin Lei Fu-Chang Gu Long Zhu Yong-Jing Chen Jun Su 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期208-221,共14页
Interest has recently emerged in potential applications of(n,2n)reactions of unstable nuclei.Challenges have arisen because of the scarcity of experimental cross-sectional data.This study aims to predict the(n,2n)reac... Interest has recently emerged in potential applications of(n,2n)reactions of unstable nuclei.Challenges have arisen because of the scarcity of experimental cross-sectional data.This study aims to predict the(n,2n)reaction cross-section of long-lived fission products based on a tensor model.This tensor model is an extension of the collaborative filtering algorithm used for nuclear data.It is based on tensor decomposition and completion to predict(n,2n)reaction cross-sections;the corresponding EXFOR data are applied as training data.The reliability of the proposed tensor model was validated by comparing the calculations with data from EXFOR and different databases.Predictions were made for long-lived fission products such as^(60)Co,^(79)Se,^(93)Zr,^(107)P,^(126)Sn,and^(137)Cs,which provide a predicted energy range to effectively transmute long-lived fission products into shorter-lived or less radioactive isotopes.This method could be a powerful tool for completing(n,2n)reaction cross-sectional data and shows the possibility of selective transmutation of nuclear waste. 展开更多
关键词 (n 2n)Reaction cross-section Tensor model Machine learning Collaborative filtering algorithm Selective transmutation
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Tidal modeling based on satellite altimetry observations of TOPEX/ Poseidon, Jason1, Jason2, and Jason3 with high prediction capability: A case study of the Baltic Sea
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作者 Alireza A.Ardalan Asiyeh Hashemifaraz 《Geodesy and Geodynamics》 EI CSCD 2024年第4期404-418,共15页
This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal modeling.We generate a time series of along-track observations a... This research aims to optimize the utilization of long-term sea level data from the TOPEX/Poseidon,Jason1,Jason2,and Jason3 altimetry missions for tidal modeling.We generate a time series of along-track observations and apply a developed method to produce tidal models with specific tidal constituents for each location.Our tidal modeling methodology follows an iterative process:partitioning sea surface height(SSH)observations into analysis/training and prediction/validation parts and ultimately identi-fying the set of tidal constituents that provide the best predictions at each time series location.The study focuses on developing 1256 time series along the altimetry tracks over the Baltic Sea,each with its own set of tidal constituents.Verification of the developed tidal models against the sSH observations within the prediction/validation part reveals mean absolute error(MAE)values ranging from 0.0334 m to 0.1349 m,with an average MAE of 0.089 m.The same validation process is conducted on the FES2014 and EOT20 global tidal models,demonstrating that our tidal model,referred to as BT23(short for Baltic Tide 2023),outperforms both models with an average MAE improvement of 0.0417 m and 0.0346 m,respectively.In addition to providing details on the development of the time series and the tidal modeling procedure,we offer the 1256 along-track time series and their associated tidal models as supplementary materials.We encourage the satellite altimetry community to utilize these resources for further research and applications. 展开更多
关键词 Satellitealtimetry Baltic Sea Ocean tide modeling Jason3 Jason2 Jason1 TOPEX/POSEIDON EOT20 FES2014
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24 Model在道路运输事故成因中的应用
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作者 刘晓露 梁志星 +2 位作者 吴君安 严玉琼 张苏 《汽车安全与节能学报》 CAS CSCD 北大核心 2024年第2期185-192,共8页
为预防道路运输事故,基于事故致因“2-4”(24 Model)模型,对2015—2021年发生的215起道路运输事故的行为原因进行研究。从个人层面和组织层面分析导致事故发生的直接原因、间接原因、根本原因及其根源原因。结果表明:发生频次最多的不... 为预防道路运输事故,基于事故致因“2-4”(24 Model)模型,对2015—2021年发生的215起道路运输事故的行为原因进行研究。从个人层面和组织层面分析导致事故发生的直接原因、间接原因、根本原因及其根源原因。结果表明:发生频次最多的不安全动作是驾驶员超速行驶(占10.67%);22.33%的道路运输事故存在管理者违章安排无资质员工上岗作业;管理者和领导者对57.67%的道路运输事故的发生有重要影响;由人为因素产生的不安全物态占比达71.53%;驾驶员、车辆安全生产管理制度欠缺或执行不到位在根本原因中尤为突出(占20.92%)。基于此,提出道路运输事故预防对策并构建出道路运输系统各因素关系图。 展开更多
关键词 汽车主动安全 道路运输事故 事故致因 2-4”模型(24 model) 对策
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基于24Model的煤炭企业安全文化提升实践研究 被引量:1
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作者 崔义 刘振宇 +6 位作者 闫寿庆 王冰山 秦东立 姜琦 郭洁 张磊 赵金坤 《煤矿安全》 CAS 北大核心 2024年第2期250-256,共7页
为了发挥安全文化在事故预防中的重要作用,运用基于事故致因“2-4”模型的安全文化水平提升方法研究某煤炭企业的安全文化建设现状并提出改进措施。首先,明确了24Model视域下的安全文化水平提升方法在我国的适用性;然后,从安全文化水平... 为了发挥安全文化在事故预防中的重要作用,运用基于事故致因“2-4”模型的安全文化水平提升方法研究某煤炭企业的安全文化建设现状并提出改进措施。首先,明确了24Model视域下的安全文化水平提升方法在我国的适用性;然后,从安全文化水平现状和安全理念2方面开展了针对该企业的实践研究;最后,提出改进措施。结果表明:该企业安全文化水平总体上要比国内或同行业的安全业绩较差的企业好,比安全业绩较好的企业差;该企业安全理念涉及32元素的13个方面;一线人员、班组长、专业人员和领导层对部分元素的理解程度不佳,并且这些元素中仅有元素3、元素4、元素6、元素13、元素16的内容在企业的安全理念有所体现。提出了14条改进的安全理念用于提高企业的安全文化水平。 展开更多
关键词 安全文化 事故致因“2-4”模型 安全理念 事故预防 安全制度 安全认知
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