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Characteristics and Seasonal Variations of PM2.5, PM10, and TSP Aerosol in Beijing

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Biomedical and Environmental Sciences 2006年第6期19卷 461-468页

作者： WEN-JIE ZHANG YE-LE SUN GUO-SHUN ZHUANG dong-qun xu Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University Beijing 100875 China Institute for Environmental Health and Related Products Safety China CDC Beijing 100021 China Center for Atmospheric Chemistry Study Department of Environmental Science ＆ Engineering Fudan University Shanghai 200433 China The Institute of Atmospheric Physics CAS LAPC Beijing 100029 China

Objective To investigate the seasonal characteristics and the sources of elements and ions with different sizes in the aerosols in Beijing. Methods Samples of particulate matters （PM2,5）, PM10, and total suspended particle （TSP） aerosols were collected simultaneously in Beijing from July 2001 to April 2003. The aerosol was chemically characterized by measuring 23 elements and 18 water-soluble ions by inductively coupled plasma-atomic emission spectroscopy （ICP-AES） and ion chromatography （IC）, respectively. Results The samples were divided into four categories： spring non-dust, spring dust, summer dust, and winter dust. TSP, PM10, and PM2.5 were most abundant in the spring dust, and the least in summer dust. The average mass ratios of PM〉10, PM2,5-10, and PM2.5 to TSP confirmed that in the spring dust both the large coarse （PM〉10） and fine particles （PM2.5） contributed significantly in summer PM2.5, PM2,5-10, and PM〉10 contributed similar fractions to TSP, and in winter much PM2.5. The seasonal variation characteristics of the elements and ions were used to divide them into four groups： crustal, pollutant, mixed, and secondary. The highest levels of crustal elements, such as AI, Fe, and Ca, were found in the dust season, the highest levels of pollutant elements and ions, such as As, F, and Cl^-, were observed in winter, and the highest levels of secondary ions （SO4^2-, NO3^-, and NH4^＋） were seen both in summer and in winter. The mixed group （Eu, Ni, and Cu） showed the characteristics of both crustal and pollutant elements. The mineral aerosol from outside Beijiug contributed more than that from the local part in all the reasons but summer, estimated using a newly developed element tracer technique.

关键词： PM2,5 PM10 TSP Seasonal variation Sources

Strong invariance principle for a counterbalanced random walk

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 370-380页

作者： TAN Hui-qun HU Zhi-shui dong Liang International Institute of Finance School of ManagementUniversity of Science and Technology of ChinaHefei 230026China Center for Basic Teaching and Experiment Nanjing University of Science and TechnologyJiangyin 214443China

We study a counterbalanced random walkS_(n)=X_(1)+…+X_(n),which is a discrete time non-Markovian process andX_(n) are given recursively as *** n≥2,X_(n) is a new independent sample from some fixed law̸=0 with a fixed probability p,andX_(n)=−X_(v(n))with probability 1−p,where v(n)is a uniform random variable on{1;…;n−1}.We apply martingale method to obtain a strong invariance principle forS_(n).

关键词： random walk martingale invariance principle

CO2-Induced Modulation of Si-O Bonds for Low Temperature Plastic Deformation of Amorphous Silica Nanoparticles with Enhanced Photoluminescence

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Energy & Environmental Materials 2024年第4期7卷 404-412页

作者： Kang Huang Wenzhuo Wu Song xu Pengfei Yan Zhongming Wei qun xu Henan Institute of Advanced Technology Zhengzhou University College of Materials Science and Engineering Zhengzhou University State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences

Modulation of Si-O bonds under mild conditions has been a challenging issue in the field of material science,which is critical to manufacture highperformance silica-based optical and photonic ***,we introduce a nondestructive technique to achieve Si-O bond rearrangement,leading to plastic deformation and photoluminescence enhancement of amorphous silica nanoparticles using supercritical carbon dioxides in EtOH/H2O solution under mild temperature.

关键词： amorphous silica anisotropic stress photoluminescence plastic deformation supercritical CO2

Measurement Uncertainty Assessment for Determination of Allura Red in Puffed Food by HPLC

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Current Medical Science 2018年第2期38卷 324-328页

作者： Ying CHEN Yun ZHAO Hua-Ming WANG Qing WANG Xi CHEN dong-qun xu Tao LI Feng YU Xiao-yong WANG Jia-fa LIU Institute of Health Inspection and Testing Hubei Provincial Center for Disease Control and Prevention Wuhan 430079 China Department of Obsterics Maternal and Child Health Hospital of Hubei Province Wuhan 430070 China Institute for Environmental Health and Related Product Safety Chinese Center for Disease Control and Prevention Beijing100021 China Public Hospital Administration of Hubei Province Health And Family Planning Commission of Hubei Province Wuhan430079 China

This study aimed to assess the measurement uncertainty of a new method for determination of allura redin food by high performance liquid chromatography （HPLC）. The uncertainty of mathematical model of allura red is based on Europe for Analytical Chemistry（EURACHEM） guidelines. The sources and components of uncertainty were calculated, including recovery, working solution, sample mass, final volume, response of standard solution, response of sample solution. The expanded uncertainty was 0.0024 （k=2）. Uncertainty of working solution was the most significant factor contributing to the total uncertainty, accounting for 86.2%. The uncertainty of volume accounted for the minimum at 0.025%. The developed method is simple and accurate, which can be used for the determination of allura redin puffed samples.

关键词： uncertainty assessment allura red high performance liquid chromatography

Genetic Analysis of Two Novel GPI Variants Disrupting H Bonds and Localization Characteristics of 55 Gene Variants Associated with Glucose-6-phosphate Isomerase Deficiency

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Current Medical Science 2024年第2期44卷 426-434页

作者： Bi-xin XI Si-ying LIU Yu-ting xu De-dong ZHANG qun HU Ai-guo LIU Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene *** disorder exhibits wide heterogeneity in its clinical manifestations and molecular characteristics,often posing challenges for precise diagnoses using conventional *** this end,this study aimed to identify the novel variants responsible for GPI deficiency in a Chinese ***:The clinical manifestations of the patient were summarized and analyzed for GPI deficiency phenotype *** compound heterozygous variants of the GPI gene,c.174C>A(***58Lys)and c.1538G>T(***513Leu),were identified using whole-exome and Sanger *** AlphaFold program and Chimera software were used to analyze the effects of compound heterozygous variants on GPI ***:By characterizing 53 GPI missense/nonsense variants from previous literature and two novel missense variants identified in this study,we found that most variants were located in exons 3,4,12,and 18,with a few localized in exons 8,9,and *** study identified novel compound heterozygous variants associated with GPI *** pathogenic variants disrupt hydrogen bonds formed by highly conserved GPI amino ***:Early family-based sequencing analyses,especially for patients with congenital anemia,can help increase diagnostic accuracy for GPI deficiency,improve child healthcare,and enable genetic counseling.

关键词： glucose-6-phosphate isomerase deficiency whole-exome sequencing compound heterozygous variants genetic characterization hydrogen bond

Management and classification of the fracture of lateral process of talus:An overview and literature update

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World Journal of Clinical Cases 2024年第15期12卷 2487-2498页

作者： Chao-qun Wang Ulrich Stockle Sheng-Nan dong xu-Gui Li Ze-Xi Ling Department of Traumatic Orthopedics The Affiliated Hospital of Wuhan Sports UniversityWuhan 430079Hubei ProvinceChina Center of Musculoskeletal Surgery Berlin CharitéMedical University HospitalBerlin 13353Germany

Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or *** recent years,as researchers from all over the world have further deepened their research on FLPT,there has been a breakthrough in the classification,and the methods and principles of clinical management have changed accordingly;however,there is still no standardized guideline for the diagnosis and management of FLPT,and there have been few relevant literature review articles related to this kind of fracture in the past at least 5 *** this article,we review the clinical classification,classification-based therapeutic recommendations,and prognosis of FLPT,with the aim of providing a reference for the clinical diagnosis and management of this infrequent fracture.

关键词： Fracture of the lateral process of the talus Fracture of the talus Hindfoot injuries Intraarticular fracture Subtalar joint

Decision and Coordination in a Closed-Loop Supply Chain with Product Recycling Under Different Low-Carbon Regulations

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Journal of the Operations Research Society of China 2024年第3期12卷 695-728页

作者： Qian-dong dong Hai-Wen xu School of Management and Engineering Nanjing UniversityNanjing210093JiangsuChina School of Science Civil Aviation Flight University of ChinaGuanghan618307SichuanChina

The implementation of recycling activity is of great significance to closed-loop supply chain ***’environmental awareness and governmental subsidy are considered in the two-echelon closed-loop supply *** types of decision-making structures are proposed under different carbon emission *** subsidy sharing mechanism is designed to resolve the channel members’conflict caused by double *** paper provides insight into the effect of environmental awareness and government subsidy under different low-carbon regulations on the supply chain benefit and social welfare via the game *** analysis results display that the government subsidy and subsidy sharing mechanism are profitably beneficial to the whole supply chain and social ***,a noteworthy result reveals that social welfare is not always directly proportional to consumers’environmental *** welfare decreases slightly with the increase in consumers’environmental awareness when consumers’environmental awareness is ***,social welfare will be significantly improved when consumers’environmental awareness increases beyond a certain threshold.

关键词： Closed-loop supply chain Recycling Coordination Social welfare Game theory Carbon emissions

A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen dong Yichao Zhu xu Guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped *** article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities *** better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between *** on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five *** the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami *** the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation

Remnants and fragments of the subducted paleo-Pacific plate:Constraints from geochemistry and geophysics

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Science China Earth Sciences 2024年第10期67卷 3041-3061页

作者： Xisheng xu Zhouchuan HUANG Dingsheng JIANG Gang ZENG Li-qun DAI State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

The subduction and rollback of the paleo-Pacific plate during Mesozoic time was the key engine for the evolution of the continental margin in eastern China. It led to lateral accretion of continental crust in Northeast China, lithospheric destruction beneath the North China Craton, and the generation of huge volumes of felsic magmatic rocks in South China. This had a profound influence on deep material cycles and the evolution of epigenetic environmental systems along the continental margin of East Asia. To fully understand the transformation of the dynamic mechanism during the subduction and rollback of the paleoPacific plate, we have attempted to trace the remnants and fragments of the subducted paleo-Pacific plate at great depths. Such remnants in both temporal and spatial dimensions can be tracked by using geochemical and geophysical approaches. Studies of the trace elements, Mg-Zn isotopes and Os-Nd-Hf-Pb-O isotopes in continental basalts from eastern China reveal a significant number of the remnants of subduction of the paleo-Pacific plate, and the initial subduction can be traced back to the Early Jurassic. Large-scale geophysical imaging unveils a multitude of high-velocity anomalies in the lower mantle of East ***, many high-velocity bodies, aptly referred to as “slab graveyards”, are nestled at the base of the lower mantle. Numerous isolated high-velocity anomalies are also present in the upper part of the lower mantle, creating conduits for the descent of the subducted slabs into the lower mantle. However, a resolution of the remnants for the subducted slabs within the lower mantle are quite low. Consequently, their impact on the lower mantle's dynamics is yet to be thoroughly investigated. Finally, the presently observed big mantle wedge(BMW) in East Asia has developed through subduction of the Pacific plate in the ***, following the rollback of the paleo-Pacific plate(began at ~145 Ma), a Cretaceous BMW system would also form above

关键词： Paleo-Pacific plate Big mantle wedge Late Mesozoic Remnants and fragments Geochemistry Geophysics