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Occurrence, Spatial Distribution, Sources and Risk Assessment of Per-and Polyfluoroalkyl Substances in Surface Sediments of the Yellow River Delta Wetland

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Journal of Ocean University of China 2024年第5期23卷 1263-1274页

作者： SUN Yu SHEN Nan ZHANG Dahai CHEN Junhui HE Xiuping JI Yinli WANG Haiyang LI Xianguo key laboratory of Marine Chemistry Theory and Technology (Ocean University of China) Ministry of Education key laboratory of Marine eco-environmental Science and Technology First Institute of Oceanography Ministry of Natural Resources Qingdao key laboratory of Analytical Technology Development and Offshore eco-environment Conservation The Yellow River Delta Sustainable Development Institute of Shandong Province

Per-and polyfluoroalkyl substances（PFASs） are emerging persistent organic pollutants（POPs）. In this study, 47 surface sediment samples were collected from the Yellow River Delta wetland（YRDW） to investigate the occurrence, spatial distribution, potential sources, and ecological risks of PFASs. Twenty-three out of 26 targeted PFASs were detected in surface sediment samples from the YRDW, with total ∑23PFASs concentrations ranging from 0.23 to 16.30 ng g-1dw and a median value of 2.27 ng g-1dw. Perfluorooctanoic acid（PFOA）, perfluorobutanoic acid（PFBA） and perfluorooctanesulfonic acid（PFOS） were the main contaminants. The detection frequency and concentration of perfluoroalkyl carboxylic acids（PFCAs） were higher than those of perfluoroalkanesulfonic acids（PFSAs）, while those of long-chain PFASs were higher than those of short-chain PFASs. The emerging PFASs substitutes were dominated by 6:2 chlorinated polyfluoroalkyl ether sulfonic acid（6:2 Cl-PFESA）. The distribution of PFASs is significantly influenced by the total organic carbon content in the sediments. The concentration of PFASs seems to be related to human activities, with high concentration levels of PFASs near locations such as beaches and villages. By using a positive matrix factorization model, the potential sources of PFASs in the region were identified as metal plating mist inhibitor and fluoropolymer manufacturing sources, metal plating industry and firefighting foam and textile treatment sources, and food packaging material sources. The risk assessment indicated that PFASs in YRDW sediments do not pose a significant ecological risk to benthic organisms in the region overall, but PFOA and PFOS exert a low to moderate risk at individual stations.

关键词： per- and polyfluoroalkyl substances risk assessment sediment source identification Yellow River Delta wetland

Causal temporal graph attention network for fault diagnosis of chemical processes

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Chinese Journal of Chemical Engineering 2024年第6期70卷 20-32页

作者： Jiaojiao Luo Zhehao Jin Heping Jin Qian Li Xu Ji Yiyang Dai School of Chemical Engineering Sichuan UniversityChengdu 610065China China three gorges Corporation Beijing 100038China

Fault detection and diagnosis(FDD)plays a significant role in ensuring the safety and stability of chemical *** the development of artificial intelligence(AI)and big data technologies,data-driven approaches with excellent performance are widely used for FDD in chemical ***,improved predictive accuracy has often been achieved through increased model complexity,which turns models into black-box methods and causes uncertainty regarding their *** this study,a causal temporal graph attention network(CTGAN)is proposed for fault diagnosis of chemical processes.A chemical causal graph is built by causal inference to represent the propagation path of *** attention mechanism and chemical causal graph were combined to help us notice the key variables relating to fault *** in the Tennessee Eastman(TE)process and the green ammonia(GA)process showed that CTGAN achieved high performance and good explainability.

关键词： Chemical processes Safety Fault diagnosis Causal discovery Attention mechanism Explainability

Impact of Initial Soil Conditions on Soil Hydrothermal and Surface Energy Fluxes in the Permafrost region of the Tibetan Plateau

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Advances in Atmospheric Sciences 2024年第4期41卷 717-736页

作者： Siqiong LUO Zihang CHEN Jingyuan WANG Tonghua WU Yao XIAO Yongping QIAO key laboratory of Land Surface Process and Climate Change in Cold and Arid regions Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Cryosphere Research Station on the Qinghai-Tibet Plateau State Key Laboratory of Cryospheric ScienceNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Accurate initial soil conditions play a crucial role in simulating soil hydrothermal and surface energy fluxes in land surface process *** study emphasized the influence of the initial soil temperature(ST)and soil moisture(SM)conditions on a land surface energy and water simulation in the permafrost region in the Tibetan Plateau(TP)using the Community Land Model version 5.0(CLM5.0).The results indicate that the default initial schemes for ST and SM in CLM5.0 were simplistic,and inaccurately represented the soil characteristics of permafrost in the TP which led to underestimating ST during the freezing period while overestimating ST and underestimating SLW during the thawing period at the XDT *** the long-term spin-up method to obtain initial soil conditions has only led to limited improvement in simulating soil hydrothermal and surface energy *** modified initial soil schemes proposed in this study comprehensively incorporate the characteristics of permafrost,which coexists with soil liquid water(SLW),and soil ice(SI)when the ST is below freezing temperature,effectively enhancing the accuracy of the simulated soil hydrothermal and surface energy ***,the modified initial soil schemes greatly improved upon the results achieved through the long-term spin-up *** modified initial soil schemes experiments resulted in a 64%,88%,and 77%reduction in the average mean bias error(MBE)of ST,and a 13%,21%,and 19%reduction in the average root-mean-square error(RMSE)of SLW compared to the default simulation ***,the average MBE of net radiation was reduced by 7%,22%,and 21%.

关键词： initial soil conditions soil temperature soil liquid water soil ice surface energy fluxes permafrost

Flow field, sedimentation, and erosion characteristics around folded linear HDPE sheet sand fence: Numerical simulation study

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Journal of Mountain Science 2024年第1期21卷 113-130页

作者： ZHANG Kai ZHANG Hailong TIAN Jianjin QU Jianjun ZHANG Xingxin WANG Zhenghui XIAO jianhua College of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730000China key laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China College of Civil Engineering Chongqing UniversityChongqing 400045China key laboratory of ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Wind and sand hazards are serious in the Milan Gobi area of the Xinjiang section of the Korla Railway. In order to ensure the safe operation of railroads, there is a need for wind and sand protection in heavily sandy areas. The wind and sand flow in the region is notably bi-directional. To shield railroads from sand, a unique sand fence made of folded linear high-density polyethylene(HDPE) is used, aligning with the principle that the dominant wind direction is perpendicular to the fence. This study employed field observations and numerical simulations to investigate the effectiveness of these HDPE sand fences in altering flow field distribution and offering protection. It also explored how these fences affect the deposition and erosion of sand particles. Findings revealed a significant reduction in wind speed near the fence corner;the minimum horizontal wind speed on the leeward side of the first sand fence(LSF) decreased dramatically from 3 m/s to 0.64 m/s. The vortex area on the LSF markedly impacted horizontal wind speeds. Within the LSF, sand deposition was a primary occurrence. As wind speeds increased, the deposition zone shrank, whereas the positive erosion zone expanded. Close to the folded corners of the HDPE sand fence, there was a notable shift from the positive erosion zone to a deposition zone. Field tests and numerical simulations confirmed the high windproof efficiency(WE) and sand resistance efficiency(SE) in the HDPE sand fence. Folded linear HDPE sheet sand fence can effectively slow down the incoming flow and reduce the sand content, thus achieving good wind and sand protection. This study provides essential theoretical guidance for the design and improvement of wind and sand protection systems in railroad engineering.

关键词： Folded linear HDPE sheet sand fence Numerical simulation Flow field characteristics Protection benefits

Exploring social-ecological system resilience in South China Karst:Quantification,interaction and policy implication

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Geography and Sustainability 2024年第2期5卷 289-301页

作者： Tiantian Chen Yuxi Wang Li Peng Chongqing key laboratory of Surface Process and ecological Restoration in the three gorges Reservoir Area Chongqing Normal UniversityChongqing 401331China Chongqing Field Observation and Research Station of Surface ecological Process in the three gorges Reservoir Area Chongqing 401331China College of Geography and Resources Sichuan Normal UniversityChengdu 610066China

China’s Grain to Green Program(GTGP),which is one of the largest payments for ecosystem services(PES)in the world,has made significant ecological improvements to the ***,current understanding of its outcomes on the social-ecological system(SES)remains ***,taking the South China Karst as an example,a SES resilience evaluation index system was constructed followed by an exploratory spatial analysis,root mean square error,and Self-Organizing Feature Map to clarify the spatiotemporal changes and relationship of SES resilience,achieve the zoning of SES resilience and provide restoration *** results showed an upward trend in social resilience from 2000 to 2020,especially its subsystem of social *** ecological resilience was stable,owing to a slightly declined ecosystem services and increased landscape ***,nearly half of the counties exhibited a distribution mismatch in SES *** was an obvious inverted U-shaped relationship of SES resilience,indicating a clear threshold effect,and the constraint relation-ship of SES resilience eased over time,demonstrating the effectiveness of the ecological restoration *** played a positive role in reducing regional SES trade-off,but this positive effect was limited,reflecting the limitations of overemphasizing the conversion from farmland to forest and *** SES resilience can be divided into four clusters,which were the key optimization zone for social system,the SES resilience safety zone,the key restoration zone for SES resilience,and the key optimization zone for ecological *** adjustments for the GTGP in these zones should be taken to achieve maximum SES benefits in the future.

关键词： SES resilience Trade-off Clustering GTGP South China Karst

Progressive fragmentation of granular assemblies within rockslides: Insights from discrete-continuous numerical modeling

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Journal of Mountain Science 2024年第4期21卷 1174-1189页

作者： JIANG Hui ZHOU Yuande WANG Jinting DU Xiuli HUANG Hailong key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China. key laboratory of the Hydrosphere Sciences of the Ministry of Water Resources Tsinghua UniversityBeijing 100084China China three gorges Construction Management Co. Ltd.Chengdu 610000China

Rock fragmentation plays a critical role in rock avalanches,yet conventional approaches such as classical granular flow models or the bonded particle model have limitations in accurately characterizing the progressive disintegration and kinematics of multi-deformable rock blocks during *** present study proposes a discrete-continuous numerical model,based on a cohesive zone model,to explicitly incorporate the progressive fragmentation and intricate interparticle interactions inherent in *** rock granular assemblies are released along an inclined plane and flow onto a horizontal *** numerical scenarios are established to incorporate variations in slope angle,initial height,friction coefficient,and particle *** evolutions of fragmentation,kinematic,runout and depositional characteristics are quantitatively analyzed and compared with experimental and field data.A positive linear relationship between the equivalent friction coefficient and the apparent friction coefficient is *** general,the granular mass predominantly exhibits characteristics of a dense granular flow,with the Savage number exhibiting a decreasing trend as the volume of mass *** process of particle breakage gradually occurs in a bottom-up manner,leading to a significant increase in the angular velocities of the rock blocks with increasing *** simulation results reproduce the field observations of inverse grading and source stratigraphy preservation in the *** propose a disintegration index that incorporates factors such as drop height,rock mass volume,and rock *** findings demonstrate a consistent linear relationship between this index and the fragmentation degree in all tested scenarios.

关键词： Rock fragmentation Rockslide Numerical modelling Discrete-continuous modelling Runout Cohesive zone model

Near-surface wind field characteristics of the desert-oasis transition zone in Dunhuang,China

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Journal of Arid Land 2024年第5期16卷 654-667页

作者： PAN Jiapeng ZHANG Kecun AN Zhishan ZHANG Yu key laboratory of Desert and Desertification&Dunhuang Gobi and Desert ecology and environment Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

The desert-oasis transition zone(DOTZ)serves as a buffer area between the desert and *** its wind field characteristics is of great significance for the prevention and control of aeolian disasters in the *** this study,we used meteorological data during 2013–2019 from the portable meteorological stations at five sites(site A on the edge of the oasis,sites B,C,and D in the DOTZ,and site O in the desert)in Dunhuang,China to analyze the near-surface wind field characteristics and their causes,as well as to reveal the key role of the DOTZ in oasis *** results showed that the mean wind speed,frequency of sand-driving wind,and directional variability of wind decreased from west to east within the DOTZ,and wind speed was significantly affected by air *** terrain influenced the prevailing winds in the region,mainly from northeast and *** some areas adjacent to the oasis were controlled by southeasterly *** indicated that the near-surface wind field characteristics of the DOTZ were caused by the combined effects of local terrain and surface hydrothermal *** site D,the annual drift potential(DP)was 24.95 vector units(VU),indicating a low wind energy environment,and the resultant drift direction(RDD)showed obvious seasonal ***,the DOTZ played an important buffering role between the desert and *** with the desert,the mean wind speed in the oasis decreased by 64.98%,and the prevailing wind direction was more *** results of this study will be useful in interpreting the aeolian activity of the DOTZ in Dunhuang.

关键词： desert-oasis transition zone near-surface wind field hydrothermal difference sand-driving wind aeolian environment Dunhuang

Determination of the Pile Drivability Using Random Forest Optimized by Particle Swarm Optimization and Bayesian Optimizer

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 871-892页

作者： Shengdong Cheng Juncheng Gao Hongning Qi State key laboratory of eco-Hydraulics in Northwest Arid region Xi’an University of TechnologyXi’an710048China School of Resources and Safety Engineering Central South UniversityChangsha410083China

Driven piles are used in many geological environments as a practical and convenient structural ***,the determination of the drivability of piles is actually of great importance in complex geotechnical *** methods of predicting pile drivability often rely on simplified physicalmodels or empirical formulas,whichmay lack accuracy or applicability in complex geological ***,this study presents a practical machine learning approach,namely a Random Forest(RF)optimized by Bayesian Optimization(BO)and Particle Swarm Optimization(PSO),which not only enhances prediction accuracy but also better adapts to varying geological environments to predict the drivability parameters of piles(i.e.,maximumcompressive stress,maximum tensile stress,and blow per foot).In addition,support vector regression,extreme gradient boosting,k nearest neighbor,and decision tree are also used and applied for comparison *** order to train and test these models,among the 4072 datasets collected with 17model inputs,3258 datasets were randomly selected for training,and the remaining 814 datasets were used for model ***,the results of these models were compared and evaluated using two performance indices,i.e.,the root mean square error(RMSE)and the coefficient of determination(R2).The results indicate that the optimized RF model achieved lower RMSE than other prediction models in predicting the three parameters,specifically 0.044,0.438,and 0.146;and higher R^(2) values than other implemented techniques,specifically 0.966,0.884,and *** addition,the sensitivity and uncertainty of the optimized RF model were analyzed using Sobol sensitivity analysis and Monte Carlo(MC)*** can be concluded that the optimized RF model could be used to predict the performance of the pile,and it may provide a useful reference for solving some problems under similar engineering conditions.

关键词： Random forest regression model pile drivability Bayesian optimization particle swarm optimization

Reducing the voltage loss of Y-series acceptor based organic solar cells via ternary/quaternary strategies

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Chinese Chemical Letters 2024年第2期35卷 70-86页

作者： Pengyu Zhang Zhiyang Zhang Heng Sun Jie Li Yi Chen Jiang Wang Chuanlang Zhan key laboratory of Advanced Materials Chemistry and Devices (AMC&DLab) of the Department of Education of Inner Mongolia Autonomous region Inner Mongolia Key Laboratory of Green CatalysisCollege of Chemistry and Environment ScienceInner Mongolia Normal UniversityHuhehot 010022China

In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies (PCEs) of organic solar cells (OSCs) have exceeded 19%.However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of *** ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency *** this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.

关键词： Organic solar cell Ternary/quaternary strategy Open-circuit voltage Voltage loss Non-radiative recombination loss