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Air pollution characteristics and their relationship with emissions and meteorology in the Yangtze River Delta region during 2014–2016

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Journal of Environmental sciences 2019年第9期31卷 8-20页

作者： Tao Ma Fengkui Duan Kebin He Yu Qin Dan Tong Guannan Geng Xuyan Liu Hui Li Shuo Yang Siqi Ye Beiyao Xu Qiang Zhang Yongliang Ma State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Tsinghua University Beijing 100084 China Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System Science Tsinghua University Beijing 100084 China National Satellite Meteorological Center Beijing 100081 China College of Resources and Environmental Sciences China Agricultural University Beijing 100094 China

With rapid economic growth and urbanization, the Yangtze River Delta(YRD) region in China has experienced serious air pollution challenges. In this study, we analyzed the air pollution characteristics and their relationship with emissions and meteorology in the YRD region during 2014–2016. In recent years, the concentrations of all air pollutants, except O3,decreased. Spatially, the PM2.5, PM10, SO2, and CO concentrations were higher in the northern YRD region, and NO2 and O3 were higher in the central YRD region. Based on the number of non-attainment days(i.e., days with air quality index greater than 100), PM2.5 was the largest contributor to air pollution in the YRD region, followed by O3, PM10, and ***, particulate matter pollution has declined gradually, while O3 pollution *** conditions mainly influenced day-to-day variations in pollutant concentrations. PM2.5 concentration was inversely related to wind speed, while O3 concentration was positively correlated with temperature and negatively correlated with relative *** air quality improvement in recent years was mainly attributed to emission *** 2014–2016, PM2.5, PM10, SO2, NOx, CO, NH3, and volatile organic compound(VOC)emissions in the YRD region were reduced by 26.3%, 29.2%, 32.4%, 8.1%, 15.9%, 4.5%, and0.3%, respectively. Regional transport also contributed to the air pollution. During regional haze periods, pollutants from North China and East China aggravated the pollution in the YRD region. Our findings suggest that emission reduction and regional joint prevention and control helped to improve the air quality in the YRD region.

关键词： Air pollution Spatiotemporal variation Meteorological condition Emission inventory Regional transport Yangtze River Delta

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Occurrence and Decay of SARS-CoV-2 in Community Sewage Drainage systems

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Engineering 2023年第7期26卷 214-219,I0008,I0009页

作者： Qian Dong 蔡俊雄刘艳臣凌海波 Qi Wang Luo-Jing Xiang Shao-Lin Yang Zheng-Sheng Lu Yi Liu Xia Huang 曲久辉 State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Hubei Provincial Academy of Eco-Environmental Sciences Wuhan 430072China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

The rapid spread of the coronavirus disease(COVID-19)pandemic in over 200 countries poses a substantial threat to human *** acute respiratory syndrome coronavirus 2(SARS-CoV-2),which causes COVID-19,can be discharged with feces into the drainage ***,a comprehensive understanding of the occurrence,presence,and potential transmission of SARS-CoV-2 in sewers,especially in community sewers,is still *** study investigated the virus occurrence by viral nucleic acid testing in vent stacks,septic tanks,and the main sewer outlets of community where confirmed patients had lived during the early days of the epidemic in Wuhan,*** results indicated that the risk of long-term emission of SARS-CoV-2 to the environment via vent stacks of buildings was low after confirmed patients were ***-CoV-2 were mainly detected in the liquid phase,as opposed to being detected in aerosols,and its RNA in the sewage of septic tanks could be detected for only four days after confirmed patients were *** surveillance of SARS-CoV-2 in sewage could be a sensitive indicator for the possible presence of asymptomatic patients in the community,though the viral concentration could be diluted more than ten times,depending on the sampling site,as indicated by the Escherichia coli *** comprehensive investigation of the community sewage drainage system is helpful to understand the occurrence characteristics of SARS-CoV-2 in sewage after excretion with feces and the feasibility of sewage surveillance for COVID-19 pandemic monitoring.

关键词： SARS-CoV-2 Transmission risk Drainage system Sewage Community

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Conditional Generative Modeling for Amorphous Multi-Element Materials

arXiv

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arXiv 2025年

作者： Li, Honglin Liu, Chuhao Guo, Yongfeng Luo, Xiaoshan Chen, Yijie Liu, Guangsheng Li, Yu Wang, Ruoyu Wang, Zhenyu Wu, Jianzhuo Ma, Cheng Xie, Zhuohang Lv, Jian Ding, Yufei Zhang, Huabin Luo, Jian Zhong, Zhicheng Li, Mufan Wang, Yanchao Li, Wan-Lu Key Laboratory of Material Simulation Methods and Software Ministry of Education College of Physics Jilin University Changchun China Aiiso Yufeng Li Family Department of Chemical and Nano Engineering University of California La Jolla San DiegoCA United States Institute of Molecular Engineering Plus College of Chemistry Fuzhou University Fuzhou China College of Chemistry and Molecular Engineering Peking University Beijing China School of Physics Nankai University Tianjin China Institute of Modern Physics Fudan University Shanghai China Program in Materials Science and Engineering University of California La Jolla San DiegoCA United States School of Artificial Intelligence and Data Science University of Science and Technology of China Hefei230026 China Suzhou Institute for Advanced Research University of Science and Technology of China Suzhou215123 China International Center of Future Science Jilin University Changchun China Department of Computer Science and Engineering University of California La Jolla San DiegoCA United States Center for Renewable Energy and Storage Technologies Physical Science and Engineering Division King Abdullah University of Science and Technology Thuwal Saudi Arabia Suzhou Lab Suzhou215123 China

Amorphous multi-element materials offer unprecedented tunability in composition and properties, yet their rational design remains challenging due to the lack of predictive structure-property relationships and the vast configurational space. Traditional modeling struggles to capture the intricate short-range order that dictates their stability and functionality. We here introduce ApolloX, a pioneering predictive framework for amorphous multi-element materials, establishing a new paradigm by integrating physics-informed generative modeling with particle swarm optimization, using chemical short-range order as an explicit constraint. By systematically navigating the disordered energy landscape, ApolloX enables the targeted design of thermodynamically stable amorphous configurations. It accurately predicts atomic-scale arrangements, including composition-driven metal clustering and amorphization trends, which are well-validated by experiments, while also guiding synthesis by leveraging sluggish diffusion to control elemental distribution and disorder. The resulting structural evolution, governed by composition, directly impacts catalytic performance, leading to improved activity and stability with increasing amorphization. This predictive-experimental synergy transforms the discovery of amorphous materials, unlocking new frontiers in catalysis, energy storage, and functional disordered systems. Copyright © 2025, The Authors. All rights reserved.

关键词： Amorphization

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Compact lithium-glass neutron beam monitor for SANS at CSNS

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Nuclear science and Techniques 2018年第9期29卷 165-170页

作者： Ke Zhou Jian-Rong Zhou Yu-Shou Song Xiao-Juan Zhou Zhao-Yang Xie Gui-An Yang Yan-Feng Wang Yuan-Bo Chen Zhi-Jia Sun Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China Dongguan Neutron Science Center Dongguan 523803China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics Beijing 100049China

A small-angle scattering neutron spectrometer for material research is under construction at the China Spallation Neutron Source. An intervening neutron beam monitor behind the sample is needed to measure the beam intensity in order to reduce the measurement uncertainty caused by beam fluctuation. Considering the mobility requirement and limited space, we proposed a compact monitor using a type of lithium-glass scintillator provided by China Building Materials Academy. Its performance was studied experimentally using ^(252)Cf and ^(60)Co *** neutron light yield of the selected scintillator was measured to be 5:3 × 10~3 photons/neutron. The feasibility of n-gamma discrimination using the charge comparison method was verified. By using the Geant4 toolkit, themonitor was modeled with precise physical processes including neutron tracking, scintillation, and optical photon transmission. The gamma sensitivity and detection efficiency were investigated in the simulation. It was concluded that a 0.5-mm-thick lithium-glass scintillator with natural lithium is an appropriate choice to satisfy both the neutron detection efficiency and gamma elimination requirements.

关键词： Neutron beam monitor Lithium glass ngamma discrimination Detection efficiency

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A homogenization method for nonlinear inhomogeneous elastic materials

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Virtual Reality & Intelligent Hardware 2021年第2期3卷 156-170页

作者： Jing ZHAO Fei ZHU Liyou XU Yong TANG Sheng LI College of Information Science and Engineering Yanshan UniversityQinhuangdaoHebei 066004China The Key Laboratory for Computer Virtual Technology and System Integration of Hebei Province QinhuangdaoHebei 066004China School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China Beijing Engineering Research Center for Virtual Simulation and Visualization Beijing 100871China

Background Fast simulation techniques are strongly favored in computer graphics,especially for the nonlinear inhomogeneous elastic *** homogenization theory is a perfect match to simulate inhomogeneous deformable objects with its coarse discretization,as it reveals how to extract information at a fine scale and to perform efficient computation with much less *** existing homogenization method is not applicable for ubiquitous nonlinear materials with the limited input deformation *** In this paper,we have proposed a homogenization method for the efficient simulation of nonlinear inhomogeneous elastic *** approach allows for a faithful approximation of fine,heterogeneous nonlinear materials with very coarse *** analysis provides the basis of a linear deformation space and modal derivatives extend the space to a nonlinear regime;based on this,we exploited modal derivatives as the input characteristic deformations for *** also present a simple elastic material model that is nonlinear and anisotropic to represent the homogenized *** nonlinearity of material deformations can be represented properly with this *** material properties for the coarsened model were solved via a constrained optimization that minimizes the weighted sum of the strain energy deviations for all input deformation *** arbitrary number of bases can be used as inputs for homogenization,and greater weights are placed on the more important low-frequency *** Based on the experimental results,this study illustrates that the homogenized material properties obtained from our method approximate the original nonlinear material behavior much better than the existing homogenization method with linear displacements,and saves orders of magnitude of computational *** The proposed homogenization method for nonlinear inhomogeneous elastic materials is capable of capturing the nonlinear dynamics of the

关键词： Physical-based simulation Homogenization theory Heterogeneous material Modal basis

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High-responsivity solar-blind photodetector based on MOCVD-grown Si-dopedβ-Ga_(2)O_(3)thin film

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Chinese Physics B 2021年第5期30卷 595-601页

作者： Yu-Song Zhi Wei-Yu Jiang Zeng Liu Yuan-Yuan Liu Xu-Long Chu Jia-Hang Liu Shan Li Zu-Yong Yan Yue-Hui Wang Pei-Gang Li Zhen-Ping Wu Wei-Hua Tang Laboratory of Information Functional Materials and Devices School of Science&State Key Laboratory of Information Photonics and Optical CommunicationsBeijing University of Posts and TelecommunicationsBeijing 100876China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China The Engineering Research Center for Semiconductor Integrated Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China China Aerospace System Simulation Technology Co. Ltd.(Beijing)Beijing 100195China College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210023China

Si-dopedβ-Ga_(2)O_(3)films are fabricated through metal-organic chemical vapor deposition(MOCVD).Solar-blind ultraviolet(UV)photodetector(PD)based on the films is fabricated by standard photolithography,and the photodetection properties are *** results show that the photocurrent increases to 11.2 mA under 200μW·cm^(-2)254 nm illumination and±20 V bias,leading to photo-responsivity as high as 788 A·W^(-1).The Si-dopedβ-Ga2O3-based PD is promised to perform solar-blind photodetection with high performance.

关键词： Si-dopedβ-Ga_(2)O_(3) metal-organic chemical vapor deposition(MOCVD) solar-blind high responsivity

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space science Mission Operation system joint test method research

Space Science Mission Operation System joint test method res...

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12th International Conference on space Operations, spaceOps 2012

作者： Wu, Haiyan Meng, Xin Zhang, Yuzhu Zou, Zimin Tong, Jizhou Xiaodong, X. Li, Dalin Center for Space Science and Applied Research Chinese Academy of Science Beijing 100190 China Graduate University Chinese Academy of Science Beijing 100049 China Space Information and Simulation Laboratory 8701 Beijing China Data and Net Center 8701 Beijing China

Testing is important for space science Satellite Ground Application system (SSSGAS) development, which usually takes a lot of time. This paper introduces a system Joint Test Platform that could be applied to SSSGAS's development, testing and verification. SJTP's purpose is to check whether SSSGAS's various subsystems and functional module interface is in line with the system interface specification so to reduce the workload of system testing. SJTP can simulate SSSGAS's various subsystems or functional module interface functions and processes in order to do debugging with the measured subsystem / function module interface;it can also simulate and test the system's process by connecting with one or more of the actual subsystem / functional modules together to emulate the complete SSSGAS. © 2012 by center for space science and Applied Research, Chinese Academy of sciences.

关键词： Testing

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Drought frequency, intensity, and exposure have increased due to historical land use and land cover changes

Communications Earth & Environment

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Communications Earth & Environment 2025年第1期6卷 1-13页

作者： Tao Tang Lin Wang Junji Cao Jun Ge Haiyun Shi Xuhui Lee State Key Laboratory of Earth System Numerical Modeling and Application Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Science Center for Earth System Numerical Simulation Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China CAS Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Joint International Research Laboratory of Atmospheric and Earth System Sciences School of Atmospheric Sciences Nanjing University Nanjing China School of Environmental Science and Engineering Southern University of Science and Technology Shenzhen China School of the Environment Yale University New Haven CT USA

Drought, a marked deficiency of surface water, has a wide adverse impact on the environment, agriculture, and the socio-economy. The global impact of land use changes on drought features and associated exposures to droughts, however, remains largely unknown. In this study, the changes of drought features are estimated by using the model simulations with and without land use change. We show that historical land use changes since 1850, mainly deforestation and crop expansion, has increased the drought frequency, duration, and severity over half of the global land area. Regions with greater activity tend to experience stronger exacerbation of drought events. Owing to their increasing frequency and prolonged duration, populations, croplands and forests are increasingly exposed to drought events, which poses serious potential impacts on human health, agriculture, and forest ecosystems. The enhanced drought events could be substantially alleviated by potential reforestation activity. Our results provide useful information for land-management-related policy-making.

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The Star Scene Modeling and Generation for Hardware-in-the-loop simulation

The Star Scene Modeling and Generation for Hardware-in-the-l...

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2018 International Conference on Computational, Modeling, simulation and Mathematical Statistics(CMSMS 2018)

作者： Ying ZHANG Hui-jie DU Yu ZHANG Yi-yuan MA Hui-yang QU Science and Technology on Special System Simulation Laboratory Beijing Simulation Center National Key Laboratory of Intelligent Manufacture System Technology for Complicated Products

The star sensor simulation system is used to test the star sensor performance on the ground, which is designed for star identification and spacecraft attitude determination of the spacecraft. The computer star scene based on the astronomical star chat is generated for hardware-in-the-loop simulation of the star sensor simulation system using OpenGL. The results of star scene generation are shown in this paper and applied in the real time star sensor simulation.

关键词： Star scene Modeling simulation Astronomical chat

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Profiling and analysis of object lazy allocation in Java programs

Profiling and analysis of object lazy allocation in Java pro...

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ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing (SNPD)

作者： Jianjun Shi Weixing Ji Lulu Zhang Yujin Gao Han Zhang Duzheng Qing School of Computer Science Beijing Institute of Technology Beijing China Science and Technology on Special System Simulation Laboratory Beijing Simulation Center Beijing China

Lazy allocation strategy allows the memory management system to defer the space allocation action of objects until they are being accessed. This paper investigates the potential benefits of a lazy allocator for Java applications. A heap tracing tool is implemented by instrumenting an existing Java virtual machine HotSpot, which records useful object manipulating events at runtime. By profiling and analyzing a large number of benchmarks, we show the potential dynamic memory management optimization opportunity in Java programs. We also designed a simulation system to demonstrate the actual effects of a lazy allocator.

关键词： Resource management Java Benchmark testing Memory management Virtual machining Color Runtime

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