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Process analysis of characteristics of the boundary layer during a heavy haze pollution episode in an inland megacity,China

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Journal of Environmental Sciences 2016年第2期28卷 138-144页

作者： Shan Wang Tingting Liao Lili Wang yang sun Xi'an Meteorological Bureau Xi'an 710016 China Plateau Atmospheric and Environment Key Laboratory of Sichuan Province College of Atmosphere Sciences Chengdu University of Information Technology Chengdu 610225 China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing 100191 China

Ground observation data from 8 meteorological stations in Xi＇an, air mass concentration data from 13 environmental quality monitoring sites in Xi＇an, as well as radiosonde observation and wind profile radar data, were used in this study. Thereby, the process,causes and boundary layer meteorological characteristics of a heavy haze episode occurring from 16 to 25 December 2013 in Xi＇an were analyzed. Principal component analysis showed that this haze pollution was mainly caused by the high-intensity emission and formation of gaseous pollutants（NO_2, CO and SO_2） and atmospheric particles（PM_（2.5）（fine particles） and PM10（respirable suspended particle）. The second cause was the relative humidity and continuous low temperature. The third cause was the allocation of the surface pressure field. The presence of a near-surface temperature inversion at the boundary layer formed favorable stratification conditions for the formation and maintenance of heavy haze pollution. The persistent thick haze layer weakened the solar radiation. Meanwhile, a warming effect in the urban canopy layer and in the transition zone from the urban friction sublayer to the urban canopy was indicated. All these conditions facilitated the maintenance and reinforcement of temperature inversion. The stable atmospheric stratification finally acted on the wind field in the boundary layer, and further weakened the exchange capacity of vertical turbulence. The superposition of a wind field with the horizontal gentle wind induced the typical air stagnation and finally caused the deterioration of air quality during this haze event.

关键词： Haze Temperature inversion Radiation Air stagnancy

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Investigation on behavior of crack penetration/deflection at interfaces in intelligent coating system

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Applied Mathematics and Mechanics(English Edition) 2015年第4期36卷 465-474页

作者： yang sun Wenjuan WANG Binbin LI Mabao LIU State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University

Based on the three-phase model, the propagation behavior of a matrix crack in an intelligent coating system is investigated by an energy criterion. The effect of the elastic mismatch parameters and the thickness of the interface layer on the ratio of the energy release rate for infinitesimal deflected and penetrated crack is evaluated with the finite element method. The results show that the ratio of the energy release rates strongly depends on the elastic mismatch al between the substrate and the driving layer. It also strongly depends on the elastic mismatch a2 between the driving layer and the sensing layer for a thinner driving layer when a primary crack reaches an interface between the substrate and the driving layer. Moreover, with the increase in the thickness of the driving layer, the dependence on a2 gradually decreases. The experimental observation on aluminum alloys monitored with intelligent coating shows that the established model can better explain the behavior of matrix crack penetration and can be used in optimization design of intelligent coating.

关键词： intelligent coating energy criterion interface crack deflection crackpenetration finite element method

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A new era of nuclear astrophysics research in China

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Chinese Science Bulletin 2012年第36期57卷 4805-4806页

作者： sun yang LIU WeiPing Department of Physics Shanghai Jiao Tong UniversityShanghai 200240China China Institute of Atomic Energy Beijing 102413China

Nuclear astrophysics is a rapidly-growing interdisciplinary branch of physics involving a close collaboration among researchers in nuclear physics,astrophysics,and observational *** origin and fate of matter in our Un... 详细信息

关键词：核天体物理中国天体物理学核物理学研究人员跨学科天文学

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Electrochemical Co-reduction of Bi(Ⅲ)and Y(Ⅲ)and Extracting Yttrium from Molten LiCl-KCl Using Liquid Bi as Cathode

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Chemical Research in Chinese Universities 2019年第1期35卷 60-64页

作者： LI Mei LIU Yichuan sun Zhongxuan HAN Wei ZHANG Milin yang Xiaoguang sun yang Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Material Science and Chemical EngineeringHarbin Engineering University Harbin 150001.P.R.China

The electrochemical reaction of Bi(Ⅲ)and co-reduction behaviour of Bi(Ⅲ)and Y(Ⅲ)ions were researched in molten LiCl-KCl on a ttmgsten(W)electrode employing a range of electrochemical *** voltammetric and square-wave voltanunetric results revealed that the reduction of Bi(Ⅲ)was a one-step process,with the exchange of three electrons on a W electrode,and *** electrochemical curves showed two reduction peaks pertaining to the formation of Bi-Y alloy compounds,because of the co-reduction of Bi(Ⅲ)and Y(Ⅲ) by metallic Y deposited on the pre-deposited Bi-coated W electrode and reacting with Bi metal in molten LiCl-KCl. Furthermore,galvanostatic electrolysis was conducted using liquid Bi as cathode to extract yttrium at different current intensities,and the extractive products were analyzed by SEM,EDS and *** results indicated that BiY intermetallic compotmd was formed in the molten LiCl-KCl-YCl3 system.

关键词： Electrochemical co-reduction:Electrochemical behaviour Bi-Y intennetallic compound Galvanostatic electrolysis

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Healthcare for Patients with Hepatitis B Virus:Analysis of 367381 Inpatient Cases in China

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Current Medical Science 2022年第3期42卷 658-665页

作者： Da ZHOU Shi-ran sun yang sun Rui MIN Center for Health Information and Statistics of Hubei Wuhan 430079China Department of Hepatobiliary Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China School of Politics and Management Wuhan UniversityWuhan 430072China School of Public Health Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Hepatitis B virus(HBV)infection,which has been recognized as an international public health challenge,has caused significant morbidity for the entire *** research focused on patients with HBV in China to examine health utilization and *** Patients hospitalized with HBV from 2017 to 2019 in tertiary hospitals in Hubei,a province located in central China,were selected as the study *** information was collected from the provincial inpatient electronic system *** and regression analyses were performed to describe the basic situation of healthcare services and determine the influencing indicators of inpatient service *** A total of 367381 cases of HBV infection were identified in the study *** of these cases were patients who were married(90.2%)and males(63%).With the great efforts by the universal coverage of the basic medical insurance(BMI)in China,the increasing rate of inpatient hospitalization for HBV was 3.5 times higher than that of the total inpatient health service cases in the study *** average age of this group was 52.84±14.10 years and 11.1%of patients paid for their own medical expenditures without *** average length of stay(LOS)was 11.10 days,and the average cost per patient was 15712.05 *** values were higher than the average level in study ***,marital status,career,payment type,and kind of hospitals significantly influenced healthcare *** and the elderly might incur higher healthcare costs than their *** The BMI operated by government has played a role in the utilization release of health services for HBV ***,researchers must pay more attention to the continuing increase in the medical expenses of this group.

关键词： healthcare utilization expenditure hepatitis B virus infection inpatients hospitalization

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Developing a better mouse model of Alzheimer disease with clinically relevant phenotypes in tau pathology

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中国药理学与毒理学杂志 2018年第9期32卷 687-688页

作者： sun An-yang Department of Neurology Shangahi Zhoupu Hospital Shanghai 201318 China Laboratory of Neurodegenerative Diseases and Molecular Imaging Shanghai University of Medicine & Health Sciences Shanghai 201318 China

OBJECTIVE Transgenic mouse model has been widely used in pathogenesis study and preclinical drug evaluation in Alzheimer disease(AD).However,key differences are found between current animal models and clinical AD patients regarding *** of complete models that recapitulate broad spectrum of human AD neuropathology restricts efficacy of research projects and leads to frequent failure in AD drug development at clinical trial *** study aims to develop better mouse models of AD through modifying key phenotype *** By crossing different single and double transgenic mice with different mutations of APP/PS1 or tau and under prion,Thy1 or PDGF-β promoter,as well as selected knockout mice,I produced a dozen of bigenic models for neuropathology *** neurochemical,behavioral and pharmacological validations were conducted in the optimized mouse *** Neuropathology phenotyping found remarkable differences in tau pathology and neurodegeneration among individual APP/PS1/tau transgenic models.I had identified a triple mouse model named FADT that showed(1) huge mature tau pathology in hippocampus and cortex;(2) abundant tau truncation,as seen in human AD brain;(3)progressive neurodegeneration;(4)selective brain atrophy in hippocampus and entorhinal cortex;(5) reproducible and late onset spatial memory defects,***,remarkable tau pathology in this FADT model is mainly driven by beta-amyloid pathology,which differs from high expression of tau in rTg4510 *** I had developed a new triple transgenic mouse model that recapitulates broad spectrum of human AD neuropathology *** study will not only establish a solid model basis for AD pathophysiology investigation and drug development,but also reveal important clues on the interaction of beta-amyloid and tau pathologies in the brain.

关键词： Alzheimer disease transgenic mice phenotypes model optimization tau pathology

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Unlocking multiplexing in deep tissue

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Science China Chemistry 2019年第2期62卷 157-158页

作者： yang sun Zhengyu Deng Yanlan Liu Weihong Tan Institute of Molecular Medicine Renji Hospital School of Medicine and College of Chemistry and Chemical EngineeringShanghai Jiao Tong University Molecular Science and Biomedicine Laboratory (MBL) State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering College of Life Sciences Aptamer Engineering Center of Hunan Province Hunan University Department of Chemistry and Department of Physiology and Functional Genomics Center for Research at the Bio/Nano InterfaceHealth Cancer Center UF Genetics Institute Mc Knight Brain Institute University of Florida

In vivo fluorescence imaging in the second near-infrared (NIR-II)window (1000-1700 nm)has been emerging as a new powerful imaging technique and demonstrated tre- mendous potential in life sciences and biomedical applications,given its advances in reducing photon scattering,light absorption,and autofluorescence [1,2].In particular,extensive efforts have been made to produce various NIR-II probes with different emission wavelengths for multiplexing purposes,as practical applications typically require concurrent detection of multiple analytes.

关键词： Unlocking multiplexing deep tissue

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Preparation of Monodisperse Spherical SiO_2 by Microwave Hydrothermal Method and Kinetics of Dehydrated Hydroxyl

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Journal of Materials Science & Technology 2010年第8期26卷 711-714页

作者： Xiaoyi Shen Yuchun Zhai yang sun Huimin Gu School of Materials and Metallurgy Northeastern University Shenyang 110004 China Educational Department of Liaoning Province Shenyang 110032 China

Monodisperse spherical SiO2 particles were successfully synthesized in 2-propanol-H2O-NH3 system by the microwave hydrothermal method using ammonia as catalyst. To investigate the influences on the size of spherical SiO2 particles, factors such as ammonia concentration, reaction temperature, stirring intensity and reactants mol ratio have been studied. The orthogonal experiments were carried out. The as-prepared SiO2 particles were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, Fourier transform infrared spectroscopy （FTIR） and differential thermal analysis （DTA）. The results indicated that the size of SiO2 particles increased greatly with the increase in ammonia concentration, temperature and reactants mol ratio, but increased slightly with the increase in stirring intensity. Monodisperse spherical Si02 particles were amorphous with perfect sphere and uniform size. Hydroxyl was detected in SiO2. Kinetic parameters were calculated, and finally the reaction rate equation of dehydrated hydroxyl was obtained.

关键词： Monodisperse spherical SiO2 particle Microwave hydrothermal method Amorphous Reaction rate

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A star-based method for precise wavelength calibration of the Chinese Space Station Telescope(CSST) slitless spectroscopic survey

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Research in Astronomy and Astrophysics 2021年第3期21卷 235-242页

作者： Hai-Bo Yuan Ding-Shan Deng yang sun Department of Astronomy Beijing Normal UniversityBeijing 100875China

The Chinese Space Station Telescope(CSST)spectroscopic survey aims to deliver high-quality low-resolution(R>200)slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag,distributed within a large survey area(17500 deg2)and covering a wide wavelength range(255-1000 nm by three bands GU,GV,and GI).As slitless spectroscopy precludes the usage of wavelength calibration lamps,wavelength calibration is one of the most challenging issues in the reduction of slitless spectra,yet it plays a key role in measuring precise radial velocities of stars and redshifts of *** this work,we propose a star-based method that can monitor and correct for possible errors in the CSST wavelength calibration using normal scientific observations,taking advantage of the facts that(ⅰ)there are about ten million stars with reliable radial velocities now available thanks to spectroscopic surveys like LAMOST,(ⅱ)the large field of view of CSST enables efficient observations of such stars in a short period of time,and(ⅲ)radial velocities of such stars can be reliably measured using only a narrow segment of CSST *** demonstrate that it is possible to achieve a wavelength calibration precision of a few km s^(-1) for the GU band,and about 10 to 20 kms^(-1) for the GV and GI bands,with only a few hundred velocity standard *** of the method to other surveys are also discussed.

关键词： methods:data analysis methods:statistical techniques:spectroscopic techniques:radial velocities stars:fundamental parameters stars:kinematics and dynamics

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Precision of the Chinese Space Station Telescope(CSST)stellar radial velocities

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Research in Astronomy and Astrophysics 2021年第4期21卷 207-215页

作者： yang sun Ding-Shan Deng Hai-Bo Yuan Department of Astronomy Beijing Normal UniversityBeijing 100875China

The Chinese Space Station Telescope(CSST)spectroscopic survey plans to deliver high-quality low-resolution(R>200)slitless spectra for hundreds of millions of targets down to a limiting magnitude of about 21 mag,covering a large survey area(17500 deg^(2))and a wide wavelength range(255-1000 nm by three bands GU,GV,and GI).In this work,we use empirical spectra of the Next Generation Spectral Library to simulate the CSST stellar spectra at R=250,and investigate their capabilities in measuring radial *** find that velocity uncertainties depend strongly on effective temperature,weakly on metallicity for only FGK stars,and hardly on surface *** is possible to deliver stellar radial velocities to a precision of about 3 kms^(-1)for AFGKM stars,and about 10 km s^(-1)for OB stars,at signal-to-noise ratio(SNR)of *** uncertainties using single GU/GV/GI band spectra are also *** the same SNR,the GU band performs best,the GV band the second best,and then the GI *** effects of spectral normalization and the imperfect template on velocity measurements are investigated and found to be very *** uncertainties caused by wavelength calibration are considered and found to be *** the possible precision of radial velocities,the CSST spectroscopic survey can enable interesting science such as searching for hyper-velocity *** of our results are also discussed.

关键词： methods:data analysis methods:statistical stars:fundamental parameters stars:kinematics and dynamics

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