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Dynamic emission characteristics and control strategies of air pollutants from motor vehicles in downtown Beijing,China

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Journal of Environmental Sciences 2024年第2期136卷 637-646页

作者： Yan Shen Tongran Wu Aiping Lian Jie Gao Fei Peng Guohua Song Xuefang Wu Yangyang Cui Xinyu Liu Yunfei Wan Jing Yan Yifeng Xue National Engineering Research Center of Urban Environmental Pollution Control Beijing Municipal Research Institute of Eco-Environmental ProtectionBeijing 100037China Beijing Municipal Ecology and Environment bureau Beijing 100048China Beijing Jiaotong University Beijing 100091China

This study combined the real-time monitoring and investigation of traffic flows to comprehensively analyze the road traffic flow and vehicle structure in downtown Beijing.A dynamic emission inventory of motor vehicle air pollutants in downtown Beijing in 2021 was established,and the impact of these emissions on air quality was simulated and quantified,and different emission reduction control scenarios were proposed to evaluate their environmental improvement effects and explore measures to mitigate the impact of pollution *** results show that the high traffic flow and the structure of the motor vehicle emissions in downtown Beijing are the main causes of severe motor vehicle *** data shows that traffic flow in central Beijing is dominated by small passenger vehicles,while the vehicle mix is better than in other regions,with 72.0%of vehicles meeting"National v"or higher emission ***,to achieve higher air quality goals,further reducing vehicle emissions is *** on dynamic traffic flow,the average daily emissions of nitrogen oxides(NOX),particulate matters(PM_(2.5))and volatile organic compounds(vOC)from motor vehicles in central Beijing are 17.7 tons,0.6 tons and 14.0 tons,respectively,accounting for 23.0%of the city’s average daily motor vehicle *** a zero-emission zone for motor vehicles were implemented in central Beijing,the annual average emission level of pollutants will be reduced by 10.4%to 21.0%.The designation of ultra-low emission zones for motor vehicles could be effective in improving the air quality in the center of Beijing.

关键词： Motor vehicle Air pollutant Emission characteristics Control strategy Beijing

Exploiting demand-side heterogeneous flexible resources in risk management of power system frequency

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Science China(Technological Sciences) 2024年第5期67卷 1612-1627页

作者： YAO Yu SONG YongHua YE ChengJin DING Yi ZHAO YuMing College of Electrical Engineering Zhejiang UniversityHangzhou310027China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SAR519000China Shenzhen Power Supply bureau Co. Ltd.Shenzhen518051China

More demand-side flexible resources(DFRs)are participating in the frequency regulation of renewable power systems,whose heterogeneous characteristics have a significant impact on the system frequency ***,selecting suitable DFRs poses a formidable challenge for independent system operators(ISO).In this paper,a reserve allocation methodology for heterogeneous DFRs is proposed to manage the risk of power system ***,a performance curve is developed to describe the cost,capacity,and response speed of ***,a clustering method for multiple distributed DFRs is conducted to calculate the aggregated performance curves and uncertainty ***,the frequency security criterion considering DFRs’performance is constructed,whose linearity makes it can be easily coupled into the system scheduling model and ***,a risk management model for DFRs considering frequency-chance-constraint is proposed to make a trade-off between cost and frequency ***,the model is transformed into mixed integer second-order cone programming(MISOCP)and solved by the commercial *** proposed model is validated by the IEEE 30 and IEEE 118 bus systems.

关键词： demand-side heterogenous flexible resources risk management of power system frequency performance curve aggregation method mixed integer second-order cone programming

Analysis of Characteristics of a Heavy Rainstorm Process in Nanchang City on July 7,2020

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Meteorological and Environmental Research 2024年第1期15卷 1-7,11页

作者： Fengling ZENG Landi ZHONG Minghua MENG Chongqing Branch Southwest Air Traffic Management BureauCivil Aviation Administration of ChinaChongqing 401120China Nanchang Meteorological bureau Nanchang 330038China

Based on the conventional observation data,dual polarization radar data and NCEP reanalysis data,the large-scale circulation background field,mesoscale conditions and formation causes of a heavy rainstorm in Nanchang on July 7,2020 were *** was found that this heavy rainstorm occurred under the weather background of the confrontation between the northward air flow behind the trough and the strong southwest warm and humid air flow to the northwest of the subtropical *** divergence at the upper level,the shear in the middle and low levels,the southward movement of cold air at the low level,unusually abundant water vapor and high unstable energy caused the heavy rainstorm *** this process,under the influence of continuous eastward movement of several strong echo cells,an obvious"train effect"was formed in Nanchang,so that the local rainfall was continuous and ***,the average of vIL was about 17 kg/m 2,and its variation characteristics were consistent with the variation trend of 5-min rainfall intensity,which had a certain indicator effect on short-term heavy *** topography of the Meiling Mountain in the west of Nanchang had a great influence on the formation and precipitation distribution of the heavy rain *** was a strong rainstorm center near the mountain,and the precipitation was obviously larger than that in the plain area.

关键词： Short-term heavy precipitation Mesoscale system Train effect Meiling landform

Health Effects of Extreme Low Temperatures and Cold Waves on Respiratory Diseases

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Biomedical and Environmental Sciences 2024年第6期37卷 682-685页

作者： Zongrui Liu Yuxia Ma Yuhan Zhao Wanci Wang Pengpeng Qin Jie Yang Bowen Cheng College of Atmospheric Sciences Key Laboratory of Semi-Arid Climate ChangeMinistry of EducationLanzhou UniversityLanzhou 730000GansuChina Minhe Meteorological bureau Minhe 810800QinghaiChina

Climate change is the most significant threat to public health and exerts myriad influences on health,including the occurrence of extreme temperature *** have demonstrated that populations will experience significantl... 详细信息

关键词： extreme Effects events.

Green Synthesis of Iron(Ⅱ,Ⅲ)-polyphenol Nanoparticles and Their Adsorption of Malachite Green

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1025-1030页

作者：胡玉 ZHOU Fan ZHANG Nan PAN Xiaobin LI Shiying ZHANG Dong LI Li 张玲帆 Department of Chemistry and Environmental Engineering Hanjiang Normal UniversityShiyan 442000China Shiyan Hydrological and Water Resources Survey bureau of Hubei Province Shiyan 442000China School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai 200237China

Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient *** obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)*** experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and ***-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting ***-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of *** removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests.

关键词： iron nanoparticles pomegranate green tea mulberry adsorption

Mobile genetic elements facilitate the transmission of antibiotic resistance genes in multidrug-resistant Enterobacteriaceae from duck farms

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Food Science and Human Wellness 2024年第2期13卷 729-735页

作者： Xin’er Zheng Dingting Xu Jinchang Yan Min Qian Peng Wang Davood Zaeim Jianzhong Han Daofeng Qu School of Food Science and Biotechnology Zhejiang Gongshang UniversityHangzhou 310035China The Second Affiliated Hospital School of MedicineZhejiang UniversityHangzhou 311100China Agricultural and rural bureau of Wangdian Town Xiuzhou DistrictJiaxing 314011China

Multidrug-resistant(MDR)Enterobacteriaceae critically threaten duck farming and public *** phenotypes,genotypes,and associated mobile genetic elements(MGEs)of MDR Enterobacteriaceae isolated from 6 duck farms in Zhejiang Province,China,were investigated.A total of 215 isolates were identified as Escherichia coli(64.65%),Klebsiella pneumoniae(12.09%),Proteus mirabilis(10.23%),Salmonella(8.84%),and Enterobacter cloacae(4.19%).Meanwhile,all isolates were resistant to at least two *** isolates carried tet(A)(85.12%),blaTEM(78.60%)and sul1(67.44%)resistance *** co-occurrence analysis showed that the resistance genes were associated with IS26 and integrons.A conjugative IncFII plasmid pSDM004 containing all the above MGEs was detected in Proteus mirabilis isolate *** isolate was resistant to 18 antibiotics and carried the blaNDM-5 ***,especially plasmids,are the primary antibiotic resistance gene transmission route in duck *** findings provide a theoretical basis for the rational use of antibiotics in farms which are substantial for evaluating public health and food safety.

关键词： Duck farm Mobile genetic element Antibiotic resistance gene Plasmid Food safety

Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： Jiaqi Wu Li Zhuo Jianliang Pei Yao Li Hongqiang Xie Jiaming Wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** complicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling

Image Recognition Model of Fraudulent Websites Based on Image Leader Decision and Inception-v3 Transfer Learning

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China Communications 2024年第1期21卷 215-227页

作者： Shengli Zhou Cheng Xu Rui Xu Weijie Ding Chao Chen Xiaoyang Xu Information Department of Zhejiang Police College Hangzhou 310053China Hangzhou Dianzi University Hangzhou 310018China Big Data Laboratory of Zhejiang Police College Hangzhou 310053China Hangzhou Public Security bureau Hangzhou 310002China

The fraudulent website image is a vital information carrier for telecom *** efficient and precise recognition of fraudulent website images is critical to combating and dealing with fraudulent *** research on image recognition of fraudulent websites is mainly carried out at the level of image feature extraction and similarity study,which have such disadvantages as difficulty in obtaining image data,insufficient image analysis,and single identification *** study develops a model based on the entropy method for image leader decision and Inception-v3 transfer learning to address these *** data processing part of the model uses a breadth search crawler to capture the image ***,the information in the images is evaluated with the entropy method,image weights are assigned,and the image leader is *** model training and prediction,the transfer learning of the Inception-v3 model is introduced into image recognition of fraudulent *** selected image leaders to train the model,multiple types of fraudulent websites are identified with high *** experiment proves that this model has a superior accuracy in recognizing images on fraudulent websites compared to other current models.

关键词： fraudulent website image leaders telecom fraud transfer learning

Incorporation of source contributions to improve the accuracy of soil heavy metal mapping using small sample sizes at a county scale

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Pedosphere 2024年第1期34卷 170-180页

作者： Jie SONG Xin WANG Dongsheng YU Jiangang LI Yanhe ZHAO Siwei WANG Lixia MA State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Chinese Academy of Sciences University Beijing 100049China Agricultural and Rural bureau of Luanping County Luanping 068250China

Estimating heavy metal(HM) distribution with high precision is the key to effectively preventing Chinese medicinal plants from being polluted by the native soil. A total of 44 surface soil samples were gathered to detect the concentrations of eight HMs(As, Hg, Cu, Cr, Ni, Zn, Pb, and Cd) in the herb growing area of Luanping County, northeastern Hebei Province, China. An absolute principal component score-multiple linear regression(APCS-MLR) model was used to quantify pollution source contributions to soil HMs. Furthermore, the source contribution rates and environmental data of each sampling point were simultaneously incorporated into a stepwise linear regression model to identify the crucial indicators for predicting soil HM spatial distributions. Results showed that 88% of Cu, 72% of Cr, and 72% of Ni came from natural sources;50% of Zn, 49% of Pb, and 59% of Cd were mainly caused by agricultural activities;and 44% of As and 56% of Hg originated from industrial activities. When three-type(natural, agricultural, and industrial) source contribution rates and environmental data were simultaneously incorporated into the stepwise linear regression model, the fitting accuracy was significantly improved and the model could explain 31%–86% of the total variance in soil HM concentrations. This study introduced three-type source contributions of each sampling point based on APCS-MLR analysis as new covariates to improve soil HM estimation precision, thus providing a new approach for predicting the spatial distribution of HMs using small sample sizes at the county scale.

关键词： absolute principal component score-multiple linear regression Chinese herbal medicine influencing factors spatial distribution stepwise multiple regression