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Analysis of China’s PM_(2.5)and ozone coordinated control strategy based on the observation data from 2015 to 2020

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Journal of Environmental Sciences 2024年第4期138卷 385-394页

作者： liuwei Kong Mengdi Song Xin li Ying liu Sihua Lu limin Zeng Yuanhang Zhang State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution *** the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM_(2.5)and ozone is urgently ***,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM_(2.5)and ozone pollution based on China’s five major air pollution *** results show that it is necessary to continue to strengthen the emission reduction in PM_(2.5)and ozone precursors,and control NO_(x) and VOCs while promoting a dramatic emission reduction in PM_(2.5).The primary method of curbing ozone pollution is to strengthen the emission control of VOCs,with a long-term strategy of achieving substantial emission reductions in NO_(x),because VOCs and NO_(x) are also precursors to PM_(2.5);hence,their reductions also contribute to the reduction in PM_(2.5).Therefore,the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM_(2.5)and ozone pollution is the only means to realize the coordinated control of PM_(2.5)and ozone.

关键词： PM_(2.5) Ozone Coordinated control Multipollutant reduction

Numerical Simulation Study of Oil-Water Emulsion Separation in an Ultrasonic Field:Effect of Coupling between Acoustic and Flow Field Parameters

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 116-125页

作者： Wang Heping lin Yinchao li Yanggui Zhang Xiaohang Wu Yi Key Laboratory of Engineering Mathematics and Advanced Computing of Nanchang Institute of Technology School of SciencesNanchang Institute of TechnologyNanchang 330099People’s Republic of China Dongguan Key Laboratory of Kunpeng Computing School of Computer ScienceGuangdong University of Science&TechnologyDongguan 523083China State Key Laboratory of Plateau Ecology and Agriculture Qinghai UniversityXining 810016China

In this study,the separation and coalescence of oil-in-water emulsions are explored in an ultrasonic field using the lattice Boltzmann *** simulating the propagation of ultrasonic waves,this study focuses on examining the effects of acoustic wave frequency,the ratio of oil to water components,and the aspect ratio of the boundary on the emulsification and separation processes of oil-water *** following conclusions are drawn.①Frequency affects the speed of oil droplet separation,leading to an increase in droplet size over *** droplets are found near the source,while smaller droplets are distributed throughout the wave web.②As the boundary aspect ratio increases,the emulsification efficiency of the droplets weakens,and the system takes longer to stabilize.③Emulsions with a higher component of oil can better resist acoustic waves.④At the same acoustic frequency,longer wavelength ultrasonic fields promote the formation of uniformly distributed,smaller oil droplets,which is beneficial to the storage of *** numerical simulation results offer insights for optimizing conditions for oil-in-water separation and serve as a numerical reference for the study of oil-in-water emulsion separation in ultrasonic environments.

关键词： lattice Boltzmann method phase separation ultrasound field

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基金共同持股下的投资行为与股价崩盘风险

金融研究 2024年第2期 187-206页

作者：曾伟徐忠李尚宸沈吉王翀中国投资有限责任公司北京100010 中国银行间市场交易商协会北京100045 香港大学金融创新及发展研究中心中国香港999077 北京大学光华管理学院、北京大学数量经济与数理金融教育部重点实验室北京100871 北京大学光华管理学院北京100871

发挥公募基金等机构投资者维护市场稳定中的作用,对我国资本市场发展意义重大,然而,我国公募基金投资行为散户化一直饱受诟病。本文建立理论模型提出,在基金共同持股情形下,面对负面信息时的竞争性抛售行为,是导致股价崩盘的重要机制。... 详细信息

发挥公募基金等机构投资者维护市场稳定中的作用,对我国资本市场发展意义重大,然而,我国公募基金投资行为散户化一直饱受诟病。本文建立理论模型提出,在基金共同持股情形下,面对负面信息时的竞争性抛售行为,是导致股价崩盘的重要机制。结合理论预测,并使用2010-2022年基金季度持仓数据,本文验证了该影响机制,发现基金重仓持股比例与股价崩盘风险显著正相关。持股基金的集中程度越高、长期持股倾向越强、业绩短期排名压力越轻,越有助于减轻基金持股对股价崩盘风险的影响。本文的结论,有助于深入理解基金共同持股下的策略性博弈与竞争行为如何导致股价暴涨暴跌,丰富了从投资者交易行为解释股价崩盘风险的相关文献。

关键词：基金共同持股投资行为股价崩盘风险负面信息竞争性抛售

A hybrid spatial-temporal deep learning prediction model of industrial methanol-to-olefins process

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 73-85页

作者： Jibin Zhou Xue li Duiping liu Feng Wang Tao Zhang Mao Ye zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Yulin Innovation Institute for Clean Energy Clean Energy Innovation Institute of Chinese Academy of SciencesYulin 719053China Xuelang Industrial Intelligence Technology Co. Ltd.Wuxi 214000China

Methanol-to-olefins,as a promising non-oil pathway for the synthesis of light olefins,has been successfully *** accurate prediction of process variables can yield significant benefits for advanced process control and *** challenge of this task is underscored by the failure of traditional methods in capturing the complex characteristics of industrial processes,such as high nonlinearities,dynamics,and data distribution shift caused by diverse operating *** this paper,we propose a novel hybrid spatial-temporal deep learning prediction model to address these ***,a unique data normalization technique called reversible instance normalization is employed to solve the problem of different data ***,convolutional neural network integrated with the self-attention mechanism are utilized to extract the temporal ***,a multi-graph convolutional network is leveraged to model the spatial ***,the extracted temporal and spatial features are fused as input into a fully connected neural network to complete the ***,the outputs are denormalized to obtain the ultimate *** monitoring results of the dynamic trends of process variables in an actual industrial methanol-to-olefins process demonstrate that our model not only achieves superior prediction performance but also can reveal complex spatial-temporal relationships using the learned attention matrices and adjacency matrices,making the model more ***,this model is deployed onto an end-to-end Industrial Internet Platform,which achieves effective practical results.

关键词： methanol-to-olefins process variables prediction spatial-temporal self-attention mechanism graph convolutional network

Multistate transition and coupled solideliquid modeling of motion process of long-runout landslide

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2694-2714页

作者： Yang Gao Yueping Yin Bin li Han Zhang Weile Wu Haoyuan Gao Institute of Geomechanics Chinese Academy of Geological SciencesChina Geological SurveyBeijing100081China Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesBeijing100081China China Institute of Geological Environment Monitoring China Geological SurveyBeijing100081China School of Geological Engineering and Geomatics Chang’an UniversityXi’an710054China

The recognition,repetition and prediction of the post-failure motion process of long-runout landslides are key scientific problems in the prevention and mitigation of geological *** this study,a new numerical method involving LPF3D based on a multialgorithm and multiconstitutive model was proposed to simulate long-runout landslides with high precision and *** following results were obtained:(a)The motion process of landslides showed a steric effect with mobility,including gradual disintegration and *** sliding mass can be divided into three states(dense,dilute and ultradilute)in the motion process,which can be solved by three dynamic regimes(friction,collision,and inertial);(b)Coupling simulation between the solid grain and liquid phases was achieved,focusing on drag force influences;(c)Different algorithms and constitutive models were employed in phase-state *** volume fraction is an important indicator to distinguish different state types and solid‒liquid *** flume experimental results were favorably validated against long-runout landslide case data;and(d)In this method,matched dynamic numerical modeling was developed to better capture the realistic motion process of long-runout landslides,and the advantages of continuum media and discrete media were combined to improve the computational accuracy and *** new method can reflect the realistic physical and mechanical processes in long-runout landslide motion and provide a suitable method for risk assessment and pre-failure prediction.

关键词： Long-runout landslide Multistate transition Mixed solid‒liquid flow Post-failure process Numerical simulation

A new method for deriving broad-band polar motion geodetic excitations

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Geodesy and Geodynamics 2024年第5期15卷 453-464页

作者： Wei Chen Jiesi Luo Jim Ray Jiancheng li Hubei Luojia Laboratory School of Geodesy and Geomatics Wuhan University National Oceanic and Atmospheric Administration Central South University

While the geodetic excitation χ(t) of polar motion p(t) is essential to improve our understanding of global mass redistributions and relative motions with respect to the terrestrial frame, the widely adopted method to derive χ(t) from p(t) has biases in both amplitude and phase responses. This study has developed a new simple but more accurate method based on the combination of the frequency- and time-domain liouville's equation(FTLE). The FTLE method has been validated not only with 6-h sampled synthetic excitation series but also with daily and 6-h sampled polar motion measurements as well as χ(t) produced by the interactive webpage tool of the International Earth Rotation and Reference Systems Service(IERS). Numerical comparisons demonstrate that χ(t) derived from the FTLE method has superior performances in both the time and frequency domains with respect to that obtained from the widely adopted method or the IERS webpage tool, provided that the input p(t)series has a length around or more than 25 years, which presents no practical limitations since the necessary polar motion data are readily available. The FTLE code is provided in the form of Mat Lab function.

关键词： Earth rotation Polar motion Geodetic excitation liouville's equation MatLab

Convex-up Style of Deformation within Grabens in Regions of Incomplete Crossing Conjugate Normal Faults: A Numerical Simulation Investigation and Case Study

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Journal of Earth Science 2024年第3期35卷 839-849页

作者： Zheng li Kai Wang Xiong Xiong Bing Zhou School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China Department of Earth Sicences Khalifa UniversityAbu DhabiUnited Arab Emirates

Crossing conjugate normal faults(CCNFs)are extensively developed in many hydrocarbon-producing basins,generally existing in the form of incomplete ***,the effect of the non-conjugate zone of the CCNFs on the conjugate relay zone post late tectonic action has not been previously *** use 3D elastic-plastic modeling to investigate the influence of incomplete(i.e.,partially intersecting)CCNFs on the pattern of deformation of strata in the intersection region.A series of model simulations were performed to examine the effects of horizontal tectonic extension,fault size,and fault depth on the deformation of conjugate relay zones of incomplete *** analyses yielded the following results.(1)The model of incomplete conjugation predicts a convex-up style of deformation in the conjugate graben region superimposed on overall subsidence under applied horizontal tectonic extension.(2)The degree of convex-up deformation of the conjugate graben depends on the influence of the non-conjugate zone on the conjugate relay zone,which varies with the amount of horizontal tectonic extension,fault size,and fault burial depth.(3)Our results indicate that incomplete CCNFs can form convex-up deformation,similar to that in the Nanpu Sag area and provide a sound understanding of hydrocarbon migration and accumulation.

关键词： incomplete conjugate normal fault conjugate graben convex-up deformation hydrocarbons Nanpu Sag tectonics.

Occurrence of viable but non-culturable(VBNC)pathogenic bacteria in tap water of public places

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 115-129页

作者： lizheng Guo Xinyan Xiao Kassim Chabi Yiting Zhang Jingjing li Su Yao Xin Yu China National Research Institute of Food and Fermentation Industries Co. Ltd.China Center of Industrial Culture CollectionBeijing 100015China Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of Environment&Ecology Xiamen UniversityXiamen 361102China

Viable but non-culturable(VBNC)bacteria have been detected in source water and effluent of drinking water treatment processes,leading to significant underestimation of viable cell *** information exists on VBNC bacteria in tap water,particularly in public *** address this gap,a comprehensive nine-month study was conducted in a major city in south-eastern China,using culture-based and quantitative PCR with propidium monoazide(PMA)dye ***-five samples were collected from five representative public places(railway station,campus,hospital,shopping mall,and institution).The findings revealed that culturable bacteria represented only 0–17.51%of the viable 16S rRNA genes,suggesting that the majority of viable bacteria existed in an uncultured or VBNC ***,opportunistic pathogens such as Escherichia coli,Enterococcus faecalis,Pseudomonas aeruginosa,Salmonella sp.,and Shigella *** primarily detected as VBNC cells,with concentrations ranging from 1.03×10^(0)to 3.01×10^(3),1.20×10^(0)to 1.42×10^(2),1.32×10^(0)to 8.82×10^(0),1.00×10^(0)to 6.71×10^(1),and 2.07×10^(0)to 1.93×10^(2)cell equivalent/100 mL,*** *** was observed in tap water after prolonged stagnation,indicating potential risks associated with bacterial *** and temporal factors accounted for 17.1%and 26.0%,respectively,of the variation in tap water community structure during the sampling period,as revealed by 16S rRNA amplicon *** study provides quantitative insights into the occurrence of VBNC bacteria in tap water and highlights the need for more sensitive monitoring methods and microbial control techniques to enhance tap water safety in public locations.

关键词： VBNC Pathogenic bacteria PMA treatment Public tap water Community structure

Vagus nerve stimulation in cerebral stroke:biological mechanisms,therapeutic modalities,clinical applications,and future directions

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Neural Regeneration Research 2024年第8期19卷 1707-1717页

作者： li Du Xuan He Xiaoxing Xiong Xu Zhang Zhihong Jian Zhenxing Yang Department of Anesthesiology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Stroke is a major disorder of the central nervous system that poses a serious threat to human life and quality of *** stro ke victims are left with long-term neurological dysfunction,which adversely affects the well-being of the individual and the broader socioeconomic ***,poststroke brain dysfunction is a major and difficult area of *** nerve stimulation is a Food and Drug Administration-approved exploratory treatment option for autis m,refractory depression,epilepsy,and Alzheimer’s *** is expected to be a novel therapeutic technique for the treatment of stroke owing to its association with multiple mechanisms such as alte ring neurotransmitters and the plasticity of central neuro *** animal models of acute ischemic stroke,vagus nerve stimulation has been shown to reduce infarct size,reduce post-stroke neurological damage,and improve learning and memory capacity in rats with stroke by reducing the inflammatory response,regulating bloodbrain barrier permeability,and promoting angiogenesis and *** present,vagus nerve stimulation includes both invasive and non-invasive vagus nerve *** studies have found that invasive vagus nerve stimulation combined with rehabilitation therapy is effective in im proving upper limb motor and cognitive abilities in stroke *** clinical studies have shown that non-invasive vagus nerve stimulation,including ear/ce rvical vagus nerve stimulation,can stimulate vagal projections to the central nervous system similarly to invasive vagus nerve stimulation and can have the same *** this paper,we first describe the multiple effects of vagus nerve stimulation in stroke,and then discuss in depth its neuroprotective mechanisms in ischemic *** go on to outline the res ults of the current major clinical applications of invasive and non-invasive vagus nerve ***,we provide a more comprehensive evaluation of the advantages and disadvantages of di

关键词： cerebral stroke neuroplasticity non-invasive vagus nerve stimulation rehabilitation vagus nerve stimulation