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Characterizing ionic species in PM_(2.5) and PM_(10) in four Pearl River Delta cities,South China

Journal of Environmental Sciences 2007年第8期19卷 939-947页

作者： LAI Sen-chao ZOU Shi-chun cao jun-ji LEE Shun-cheng HO Kin-fai School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China. Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇ an 710075 China

PM2.5 and PM10 samples were collected at four major cities in the Pearl River Delta （PRD）, South China, during winter and summer in 2002. Six water-soluble ions, Na^＋, NH4＋, K^＋, Cl^-, NO3^- and SO4^2- were measured using ion chromatography. On average, ionic species accounted for 53.3% and 40.5% for PM2.5 and PM10, respectively in winter and 39.4% and 35.2%, respectively in summer. Secondary ions such as sulfate, nitrate and ammonium accounted for the major part of the total ionic species. Sulfate was the most abundant species followed by nitrate. Overall, a regional pollution tendency was shown that there were higher concentrations of sulfate, nitrate and ammonium in Guangzhou City than those in the other PRD cities. Significant seasonal variations were also observed with higher levels of species in winter but lower in summer. The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well. NO3^-/SO4^2- ratio indicated that mobile sources have considerably contribution to the urban aerosol, and stationary sources should not be neglected. Besides the primary emissions, complex atmospheric reactions under favorable weather conditions should be paid more attention for the control of primary emission in the PRD region.

关键词： water-soluble ions seasonal and spatial variations Pearl River Delta

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Carbonaceous aerosols in PM_(10) and pollution gases in winter in Beijing

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Journal of Environmental Sciences 2007年第5期19卷 564-571页

作者： ZHANG Ren-jian cao jun-ji LEE Shun-cheng SHEN Zhen-xing HO Kin-Fai Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences START Regional Center for Temperate East Asia Beijing 100029 China Institute of Earth Environment Chinese Academy of SciencesXi＇an 710075China Research Center for Urban Environmental Technology and Management Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong China Department of Environmental Science and Technology Xi＇an Jiao Tong University Xi＇an 710049 China

An intensive observation of organic carbon （OC） and element carbon （EC） in PM10 and gaseous materials （SO2, CO, and O3,） was conducted continuously to assess the characteristics of wintertime carbonaceous aerosols in an urban area of Beijing, China. Results showed that the averaged total carbon （TC） and PM10 concentrations in observation period are 30.2±120.4 and 172.6±198.3 μ/m^3 respectively. Average OC concentration in nighttime （24.9±19.6 μ/m^3 was 40% higher than that in daytime （17.7±10.9 μ/m^3. Average EC concentrations in daytime （8.8±15.2 μ/m^3 was close to that in nighttime （8.9±15.1 μ/m^3. The OC/EC ratios in nighttime ranging from 2.4 to 2.7 are higher than that in daytime ranging from 1.9 to 2.0. The concentrations of OC, EC, PM10 were low with strong winds and high with weak winds. The OC and EC were well correlated with PM10, CO and SO2, which implies they have similar sources. OC and EC were not well correlated with O3. By considering variation of OC/EC ratios in daytime and night time, correlations between OC and O3, and meteorological condition, we speculated that OC and EC in Beijing PM10 were emitted as the primary particulate form. Emission of motor vehicle with low OC/EC ratio and coal combustion sources with high OC/EC ratio are probably the dominant sources for carbonaceous aerosols in Beijing in winter. A simple method was used to estimate the relative contribution of sources to carbonaceous aerosols in Beijing PM10. Motor vehicle source accounts for 80% and 68%, while coal combustion accounts for 20% and 32% in daytime and nighttime, respectively in Beijing. Averagely, the motor vehicle and coal combustion accounted for 74% and 26%, respectively, for carbonaceous aerosols during the observation period. It points to the motor vehicle is dominant emission for carbonaceous aerosols in Beijing PM10 in winter period, which should be paid attention to control high level of PM10 in Beijing effectively.

关键词： organic carbon elemental carbon diurnal variation PM10

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Characteristics of indoor/outdoor PM_(2.5) and elemental components in generic urban, roadside and industrial plant areas of Guangzhou City, China

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Journal of Environmental Sciences 2007年第1期19卷 35-43页

作者： HUANG Hong LEE Shun-cheng cao jun-ji ZOU Chang-wei CHEN Xin-geng FAN Shao-jia School of Chemistry and Environment South China Normal University Guangzhou 510006 China Department of Civil and Structural Engineering Hong Kong Polytechnic University Hang Hum Kowloon Hong Kong Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 China School of Environmental Science and Engineering Nanchang University Nanchang 330029 China School of Environmental Science and Engineering SunYatSen University Guangzhou 510275 China

Quantitative information on mass concentrations and other characteristics, such as spatial distribution, seasonal variation, indoor/outdoor （I/O） ratio, correlations and sources, of indoor and outdoor PM2.5 and elemental components in Guangzhou City were provided. Mass concentration of PM2.5 and elemental components were determined by standard weight method and proton-induced X-ray emission （PIXE） method. 18 elements were detected, the results showed positive results. Average indoor and outdoor PM2.5 concentrations in nine sites were in the range of 67.7-74.5μg/m^3 for summer period, and 109.9-123.7 μg/m^3 for winter period, respectively. The sum of 18 elements average concentrations were 5362.6-5533.4 ng/m^3 for summer period, and 8416.8-8900.6 ng/m^3 for winter period, respectively. Average concentrations of PM2.5 and element components showed obvious spatial characteristic, that the concentrations in roadside area and in industrial plant area were higher than those in generic urban area. An obvious seasonal variation characteristic was found for PM2.5 and elemental components, that the concentrations in winter were higher than that in summer. The I/O ratio of PM2.5 and some elemental components presented larger than 1 sometimes. According to indoor/outdoor correlation of PM2.5 and element concentrations, it was found that there were often good relationships between indoor and outdoor concentrations. Enrichment factors were calculated to evaluate anthropogenic versus natural elements sources.

关键词： PM2.5 elemental components indoor air

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Chemical characteristics of aerosol particles (PM_(2.5)) at a site of Horqin Sand-land in northeast China

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Journal of Environmental Sciences 2006年第4期18卷 701-707页

作者： SHEN Zhen-xing cao jun-ji LI Xu-xiang WANG Ya-qiang jiE Dong-mei ZHANG Xiao-ye Department of Environmental Science and Engineering Xi＇an Jiaotong University Xi＇an 710049 China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi＇an 710075 China Chinese Academy of Meteorological Sciences Beijing 100081 China Urban and Environment Science College Northeast Normal University Changchun 130024 China

The objective of this study was to characterize the mass concentration and chemical composition of aerosol particles（PM2.5） collected at Tongliao（Inner Mongolia Autonomous Region, China）, a site in Horqin Sand-land in northeast China. During spring 2005, the mass concentration for PM2.5 was （126±71）μg/m^3 in average. Five dust storm events were monitored with higher concentration of （255 ± 77）μg/m^3 in average than the non dusty days of （106 ± 44）μg/m^3. Concentrations for 20 elements were obtained by the PIXE method. Mass concentrations of ALl, Mg, Si, K, Ca, Ti, Mn, and V, which increased with the PM2.5 concentration, were higher than the pollution elements （S, Cl, Zn, Ar, Se, Br, and Pb）. Enrichment factor relative to crust material was also calculated, which showed dust trace elements were mainly from earth upper crust and pollution elements were dominated the anthropogenic aerosols. The Si/Al, Ca/Al, and Fe/Al ratios in PM2.5 samples at Tongliao were 4.07, 0.94, and 0.82, respectively, which were remarkably different with those on other source regions, such as ＂Western desert source region＂, ＂North desert source region＂ and central Asia source. Air mass back-trajectory analysis identified three kinds of general pathways were associated with the aerosol particle transport to Tongliao, but have the similar elemental ratios, implying that elemental signatures for dust aerosol from Horqin Sand-land were different with other regions.

关键词： dust aerosol mass concentration elemental composition transport pathway

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Quantitative characterizations of anisotropic dynamic properties in organic-rich shale with different kerogen content

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Petroleum Science 2024年第2期21卷 855-865页

作者： jian-Yong Xie Yan-Ping Fang Xing-Hua Wu jian'er Zhao jun-Cheng Dai jun-Xing cao ji-Xin Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu610059SichuanChina Key Lab of Earth Exploration&Information Techniques of Ministry of Education Geophysical InstituteChengdu University of TechnologyChengdu610059SichuanChina PetroChina Southwest Oil&Gasfield Company Chengdu610017SichuanChina

Understanding the quantitative responses of anisotropic dynamic properties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exploration and *** controlled experiments with a single variable is challenging for natural shales due to their high variations in components,diagenesis conditions,or pore *** employed the hot-pressing technique to construct 11 well-controlled artificial shale with varying *** artificial shale samples were successive machined into prismatic shape for ultrasonic measurements along different *** revealed bedding perpendicular P-wave velocities are more sensitive to the increasing KC than bedding paralleling velocities due to the preferential alignments of *** elastic stiffnesses except C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Apparent dynamic mechanical parameters(v and E)were found to have linear correlation with the true ones from complete anisotropic equations independent of KC,which hold value towards the interpretation of well logs consistently across formations,Anisotropic mechanical parameters(ΔE and brittlenessΔB)tend to decrease with the reducing KC,withΔB showing great sensitivity to KC *** the range of low KC(10%)shale,compilation of data from natural organic rich-shales globally verified the similar systematic relationships that can be empirically used to predict the fraction of KC in shales.

关键词： Elastic properties Organic shale Anisotropy Kerogen content Physical modeling

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Regulating the electronic structure of Ir single atoms by ZrO_(2)nanoparticles for enhanced catalytic oxidation of formaldehyde at room temperature

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Chinese Chemical Letters 2024年第7期35卷 200-205页

作者： Shiqi Peng Yongfang Rao Tan Li Yufei Zhang jun-ji cao Shuncheng Lee Yu Huang Key Laboratory of Aerosol Chemistry&Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of Sciences(CAS)Xi’an 710061China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China School of Environment and Energy South China University of TechnologyGuangzhou 51006China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains ***,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was *** optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir *** specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to *** functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)*** work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.

关键词： ZrO_(2)nanoparticles Ir single atoms Electronic structure Formaldehyde Catalytic oxidation

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泮托拉唑钠肠溶胶囊在健康人体的药动学和生物等效性

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中国药学杂志 2008年第8期43卷 617-620页

作者：曹继军辽东学院医学院辽宁丹东118000

目的评价2种泮托拉唑钠肠溶胶囊(抗溃疡药)的生物等效性。方法20名男性健康志愿者随机交叉单剂量分别口服泮托拉唑钠试验和参比制剂40mg;用HPLC内标法测定其血药浓度,用DAS软件计算药动学参数,考察其生物等效性。结果2制剂在健康人体的... 详细信息

目的评价2种泮托拉唑钠肠溶胶囊(抗溃疡药)的生物等效性。方法20名男性健康志愿者随机交叉单剂量分别口服泮托拉唑钠试验和参比制剂40mg;用HPLC内标法测定其血药浓度,用DAS软件计算药动学参数,考察其生物等效性。结果2制剂在健康人体的药-时曲线符合二房室开放模型,主要药动学参数:t1/2分别为(1.875±0.636),(1.860±0.785)h;tmax(3.083±0.393),(3.028±0.436)h;ρmax(2.969±0.616),(2.961±0.493)mg.L-1;AUC0-t(8.478±4.493),(8.460±4.293)mg.h.L-1;相对生物利用度为(100.0±9.0)%。结论2种制剂具有生物等效性。

关键词：泮托拉唑钠肠溶胶囊药动学 HPLC内标法生物等效性

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Insights into photocatalytic mechanism over a novel Cu_(2)WS_(4)/MoS_(2) S-scheme heterojunction

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Rare Metals 2024年第7期43卷 3118-3133页

作者： Wei Zhao ji-Hui cao jun-jie Liao Yun Liu Xiao-jun Zeng jun-Yu Shen Xue-Kun Hong Yang Guo He-Hua Zeng Ya-Zi Liu School of Materials Engineering Jiangsu Key Laboratory of Advanced Functional MaterialsSchool of Electronic and Information EngineeringChangshu Institute of TechnologyChangshu215500China School of Chemistry and Chemical Engineering Changji UniversityChangji 831100China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control Ministry of Ecology and EnvironmentNanjing Institute of Environmental SciencesNanjing 210023China School of Environment Jiangsu Engineering Lab of Water and Soil Eco-RemediationNanjing Normal UniversityNanjing 210023China Department of Chemical Engineering Curtin UniversityPerthWA6845Australia

A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental *** the as-prepared photocatalysts,the Cu_(2)WS_(4)/MoS_(2)-8%heterojunc tion photoc atalyst demonstrates the optimal photocatalytic performance,with the catalytic oxidation efficiency of tetracycline(TC)and the catalytic reduction efficiency of Cr^(6+)reaching 93.3%and 82.1%,*** excellent catalytic properties of Cu_(2)WS_(4)/MoS_(2) heterojunction photocatalysts are attributed to the effective separation pathways of charges and the presence of S-scheme heterojunctions,together with stronger redox *** is speculated that the photogenerated carrier migration path of the Cu_(2)WS_(4)/MoS_(2) catalyst follows the typical S-scheme photocatalytic mechanism,which is verified by the in-depth experimental study and simulated calculations including the electron paramagnetic resonance(EPR)analysis,free radical quenching experiments,charge density distribution,and simulated built-in electric field formation at the interface,which acts as driving force to promote the separation of photoinduced electrons and ***,the photocatalytic mechanism of S-scheme photogenerated carrier migration for the Cu_(2)WS_(4)/MoS_(2) catalyst is revealed based on the systematic experimental techniques and simulated calculations,accounting for its superior photocatalytic oxidation and reduction *** study provides inspiring implications to develop high-efficient S-scheme photocatalytic systems for versatile applications in solarenergy conversion.

关键词： Cu_(2)WS_(4)/MoS_(2) S-scheme Heterojunction Photocatalysis

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Multi-scenario land use prediction and layout optimization in Nanjing Metropolitan Area based on the PLUS model

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Journal of Geographical Sciences 2024年第7期34卷 1415-1436页

作者： cao ji cao Weidong cao Yuhong WANG Xuewei ZHANG Yizhen MA jinji School of Geography and Tourism Anhui Normal UniversityWuhuAnhui241002China School of Ecology and Environment Anhui Normal UniversityWuhuAnhui241002China

The metropolitan area is a crucial spatial element in promoting new urbanization in *** possesses theoretical and empirical value in the determination of the evolutionary patterns and development trends necessary for regional integration and high-quality *** study focused on Nanjing Metropolitan Area,the first national metropolitan area in China,and established three development scenarios by combining ecological–economic spatial conflict(EESC)zones and national key ecological functional *** scenarios simulate the spatial distribution of future land use and land cover change(LUCC)using the development zone planning function of the patch generation land use simulation(PLUS)*** results show that:(1)Between 2000 and 2020,the most prominent characteristics of land use change were largely the massive expansion of built-up land and the significant decline of farmland,while changes in the area of ecological land were less evident.(2)EESC areas experienced significant changes over the past 20 years,but the overall level of conflict was *** land was the main land use type in the lowest-conflict area,while built-up land was the main land use type in the highest-conflict area.(3)From 2030 to 2050,further expansion of built-up areas is expected,with continued decrease of *** regulation of these land use changes can be achieved through different development zone *** economic development scenario had the largest built-up land area,while the ecological protection scenario had the largest farmland *** study simulates the spatial pattern changes in the metropolitan area based on spatial conflict patterns and national main functional area planning process,providing a scientific reference for future spatial planning and management.

关键词： land use change spatial conflict patch-generating simulation land use prediction Nanjing Metropolitan Area

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Advances in non-invasive imaging of proteinopathies in animal models of neurodegenerative diseases

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Neural Regeneration Research 2024年第10期19卷 2115-2116页

作者： Lei cao Bin ji Ruiqing Ni Changes Technology Corporation Ltd. ShanghaiChina Fudan University ShanghaiChina School of Pharmacy Fudan UniversityShanghaiChina Institute for Biomedical Engineering University of Zurich&ETH Zurich Institute for Regenerative MedicineUniversity of ZurichZurichSwitzerland

Neurodegenerative diseases,including Alzheimer's disease(AD),frontotemporal dementia,Parkinson's disease,and dementia with Lewy bodies,represent tremendous unmet clinical needs.A common feature of these diseases is the aberrant cerebral accumulation of pathological protein aggregates,affecting selectively vulnerable circuits in a disease-specific *** studies have established a relationship between abnormal aggregation and neuronal dysfunction or loss,suggesting multifactorial pathogenesis mechanisms in these neurodegenerative disorders.

关键词： diseases degenerative clinical

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