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Journal of Environmental Sciences 2012年第1期24卷 72-77页

作者： Xinming Wang Xiang Ding Xiaoxin Fu Quanfu He Shaoyi Wang Francois Bernard Xiuying Zhao Dui Wu State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Guangzhou 510640China Graduate University of Chinese Academy of Sciences Beijing 100049China Guangzhou Environmental Monitoring Center Guangzhou 510030China Institute of Tropical and Marine Meteorology China Meteorological AgencyGuangzhou 510080China

During November–December 2010 aerosol scattering coefficients were monitored using a single-waved （525 nm） Nephelometer at a regional monitoring station in the central Pearl River Delta region and 24-hr fine particle （PM 2.5） samples were also collected during the period using quartz filters for the analysis of major chemical components including organic carbon （OC）,elemental carbon （EC）,sulfate,nitrate and *** average,these five components accounted for about 85% of PM 2.5 mass and contributed 42% （OC）,19% （SO 4 2 -）,12% （NO 3 -）,8.4% （NH 4＋） and 3.7% （EC）,to PM 2.5 mass.A relatively higher mass scattering efficiency of 5.3 m 2/g was obtained for fine particles based on the linear regression between scattering coefficients and PM 2.5 mass *** extinction budget based on IMPROVE approach revealed that ammonium sulfate,particulate organic matter,ammonium nitrate and EC in average contributed about 32%,28%,20% and 6% to the light extinction coefficients,respectively.

关键词： scattering coefficients visibility fine particle (PM 2.5) chemical compositions

Effect of chemical compositions on Temperature Susceptibility of Bitumens

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Journal of Wuhan University of Technology(Materials Science) 2010年第4期25卷 669-673页

作者：梁永胜余剑英 Key Laboratory of Silicate Materials Science and Engineering of Education Ministry Wuhan University of Technology Inner Mongolia High-grade High Way Construction and Development Co. Ltd

The viscosity of five bitumens was measured at different temperatures and the viscosity-temperature relationship was developed to evaluate the temperature susceptibility of different bitumens. The generic fractions （i e, saturates, aromatics, resins and asphaltenes） of the bitumens were separated and tested by thin-layer chromatography with flame ionization detection （TLC-FID） and the effect of chemical compositions on temperature susceptibility of bitumens was analyzed using the linear regression method. The experimental results show that the four generic fractions play an inconsistent role in the temperature susceptibility of bitumens and the correlation degree of each fraction is somewhat different. The existence of aromatics and asphaltenes can lower the sensitivity to temperature changes whereas saturates and resins may have an adverse impact on the temperature susceptibility of bitumens. As for the correlation degrees, resins show the closest correlation with the temperature susceptibility of bitumens, then asphaltenes and aromatics, and the correlation between temperature susceptibility and saturates is relatively weak.

关键词： bitumen temperature susceptibility chemical compositions viscosity

chemical compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens

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Agricultural Science & Technology 2008年第2期9卷 90-92页

作者：周劲松熊辉岩杨春江焦迎春盛海彦浙江建设职业技术学院浙江杭州311231 青海大学青海西宁810016

The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil.

关键词： Armillaria luteo-rirens Volatile oil chemical compositions GC-MS

A Comparative Study on chemical compositions of Hippophae rhamnoides *** and *** form China

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A Comparative Study on Chemical Compositions of Hippophae rh...

Effects of nitrogen concentrations on the growth and chemical compositions of Phaeodactylum tricornutum

第七届全国系统与进化植物学青年学术研讨会

作者： TIAN Chun-Jie, NAN Peng, TANG Xiao-Shu, LEI Yi-Don , CHEN Jia-Kuan, ZHONG Yang (Institute of Biodiversity Sciences, Fudan University, Shanghai 200433, China)

The inter-population variability of chemical composition of Hippophae rhamnoides subsp. yunnanensis and subsp. sinensis from fourteen populations in China were analysed by GC-MS. 45 compounds are represented and ident... 详细信息

关键词： Hippophae rhamnoides chemical compositions

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Effects of nitrogen concentrations on the growth and chemica...

Spatial and Temporal Variability of PM2.5 chemical compositions and Characteristics of Pollution Episodes in Guanzhong Plain

中国海洋湖沼学会藻类学分会第七届会员大会暨第十四次学术讨论会

作者： Cai Zhuoping Duan Shunshan(Institute of Hydrobiology,Jinan University Guangzhou 510632,China)

Marine diatom Phaeodactylum tricornutum is a phytoplankton species that has been served as an important food source or feed additive in the rearing of aquatic animals like shrimp and *** recent years,however,occurrences of red tides due to the over proliferation of this microalga along the coast of Hainan province and Shangdong province have been reported,which potentially devastated the aquaculture around and destroyed the natural marine ecosystems,with a tremendous economic *** the other hand,nitrogen,an essential element for plant growth,has been believed to be one of the most important,nutritional factors regulating the growth and metabolism of ***,relatively scarce information is available concerning the growth and chemical compositions of this alga in response to nitrogen concentrations,standing on the viewpoint that Phaeodactylum tricornutum may be a red tide-causative marine microalga in recent *** order to reveal the effects of different nitrogen concentrations on the growth and some chemical compositions in Phaeodactylum tricornutum,algal cell density,biomass,soluble sugar,protein and chlorophyll a were investigated in laboratory cultures by employing low nitrogen(LN,44 μM NaNO),medium nitrogen(MN,880μM NaNO)and high nitrogen(HN, 4400 μM NaNO)*** results indicated that cell density,specific growth rate and cell biomass of Phaeodactylum tricornutum were increased obviously with the increasing of N *** were 149.50×10 ***,0.37 d,and 209.33 μ*** LN condition,whereas they were 951.67×10 ***,0.67 d,and 806.00 μ***,under HN condition at the 10day during the stationary ***,the contents of soluble sugar, protein and chlorophyll a were significantly affected by different nitrogen concentrations,which were approximately 2.5,1.5 and 15 times respectively higher in HN treatment than those in LN *** can be concluded from the present study that high nitrogen concentration can accel

关键词： nitrogen concentrations growth chemical compositions Phaeodactylum tricornutum

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Spatial and Temporal Variability of PM2.5 Chemical Compositi...

Heavy haze pollution during the COVID-19 lockdown in the Beijing-Tianjin-Hebei region,China

第八届全国大气细及超细粒子技术研讨会暨PM_(2.5)源谱交流会

作者： Xinyi Niu Junji Cao Zhenxing Shen Hongmei Xu Ting Zhang Rong Zhang School of Human Settlements and Civil Engineering Xi'an Jiaotong University Key Lab of Aerosol Chemistry & Physics Institute of Earth Environment Chinese Academy of Sciences Institute of Global Environmental Change Xi'an Jiaotong University Department of Environmental Science and Engineering Xi'an Jiaotong University

Particulate matter pollution is a serious environmental problem which influencing air quality,regional and global climates,and humanhealth in *** year of fine aerosol samples(PM) were collected at Guanzhong Plain with six sampling sites in different cities from March2012 to *** 24-h average mass concentration of PM was 134.7μg/m,which was high enough to raise serious concerns over the air quality in Guanzhong *** of the six sites exhibited highest OC and EC values in winter,and EC levels always varied with OC concentrations and the variabilityin OC was *** contributions of secondary species SO,NO and NH in total ions were greatest,and the high concentrations in winter were mainly due to emissions from coalcombustion and biomass *** autumn the haze days were severest in Xi’an city with similar tendency of PMvariations,and it was proved that biomass burning was the main emission source of the regional *** winter pollution episodes,the pollution patterns in Guanzhong Plain are similar which were resulted from strong secondary reactions and coal *** addition,mitigating primary particulate emissions including incomplete combustion of coal andbiomass,engine exhaust,and fugitive dust,reducing the emissionsof secondary aerosol precursors including SO,NO,and NH are both importantfor reducing the environmental,economic and health impacts from PM pollutions.

关键词： Guanzhong Plain PM2.5 chemical compositions Pollution episode

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Journal of Environmental Sciences 2022年第4期34卷 170-178页

作者： Xin Zhang Zhongzhi Zhang Zhisheng Xiao Guigang Tang Hong Li Rui Gao Xu Dao Yeyao Wang Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China China National Environmental Monitoring Centre Beijing 100012China

To investigate the characteristics of particulate matter with an aerodynamic diameter less than 2.5μm(PM_(2.5))and its chemical compositions in the Beijing-Tianjin-Hebei(BTH)region of China during the novel coronavirus disease(COVID-19)lockdown,the ground-based data of PM_(2.5),trace gases,water-soluble inorganic ions,and organic and elemental carbon were analyzed in three typical cities(Beijing,Tianjin,and Baoding)in the BTH region of China from 5-15 February *** PM_(2.5)source apportionment was established by combining the weather research and forecasting model and comprehensive air quality model with extensions(WRF-CAMx).The results showed that the maximum daily PM_(2.5)concentration reached the heavy pollution level(>150μg/m^(3))in the above three *** sum concentration of SO_(4)^(2-),NO_(3)^(-)and NH_(4)^(+)played a dominant position in PM_(2.5)chemical compositions of Beijing,Tianjin,and Baoding;secondary transformation of gaseous pollutants contributed significantly to PM_(2.5)generation,and the secondary transformation was enhanced as the increased PM_(2.5)*** results of WRF-CAMx showed obviously inter-transport of PM_(2.5)in the BTH region;the contribution of transportation source decreased significantly than previous reports in Beijing,Tianjin,and Baoding during the COVID-19 lockdown;but the contribution of industrial and residential emission sources increased significantly with the increase of PM_(2.5)concentration,and industry emission sources contributed the most to PM_(2.5)***,control policies should be devoted to reducing industrial emissions and regional joint control strategies to mitigate haze pollution.

关键词： COVID-19 lockdown Heavy haze pollution chemical compositions Source apportionment Beijing-Tianjin-Hebei region

Progressively narrow the gap of PM_(2.5) pollution characteristics at urban and suburban sites in a megacity of Sichuan Basin, China

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Journal of Environmental Sciences 2023年第4期126卷 708-721页

作者： Ning Wang Li Zhou Miao Feng Tianli Song Zhuoran Zhao Danlin Song Qinwen Tan Fumo Yang College of Architecture and Environment Sichuan UniversityChengdu 610065China Chengdu Academy of Environmental Sciences Chengdu 610072China

Nowadays,the fine particle pollution is still severe in some megacities of China,especially in the Sichuan Basin,southwestern *** order to understand the causes,sources,and impacts of fine particles,we collected PM_(2.5)samples and analyzed their chemical composition in typical months from July 2018 to May 2019 at an urban and a suburban (background) site of Chengdu,a megacity in this *** daily average concentrations of PM_(2.5)ranged from5.6-102.3μg/m^(3)and 4.3-110.4μg/m^(3)at each *** inorganics and organic matters were the major components in PM_(2.5)at both *** proportion of nitrate in PM_(2.5)has exceeded sulfate and become the primary inorganic ***_(2)was easier to transform into sulfate in urban areas because of Mn-catalytic heterogeneous *** contrast,NO_(2)was easily converted in suburbs with high aerosol water ***,organic carbon in urban was much greater than that in rural,other than elemental *** Cr and As were the key cancer risk *** main sources of PM_(2.5)in urban and suburban areas were all secondary aerosols (42.9%,32.1%),combustion (16.0%,25.2%) and vehicle emission (15.2%,19.2%).From clean period to pollution period,the contributions from combustion and secondary aerosols increased *** addition to tightening vehicle controls,urban areas need to restrict emissions from steel smelters,and suburbs need to minimize coal and biomass combustion in autumn and winter.

关键词： PM_(2.5) Seasonal variation Regional characteristics chemical compositions Source apportionment Chengdu

Physicochemical Properties and Gasification Reactivity of the Ultrafine Semi-char derived from a Bench-scale Fluidized Bed Gasifier

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Journal of Thermal Science 2017年第4期26卷 362-370页

作者： ZHANG Yukui ZHANG Haixia ZHU Zhiping NA Yongjie LU Qinggang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Zhtmdong coalfield is the largest intact coalfield worldwide and fluidized bed gasification has been considered as a promising way to achieve its clean and efficient utilization. The purpose of this study is to investigate the phy- sicochemical properties and gasification reactivity of the ultrafme semi-char, derived from a bench-scale fluidized bed gasifier, using Zhundong coal as fuel. The results obtained are as follows. In comparison to the raw coal, the carbon and ash content of the semi-char increase after partial gasification, but the ash fusion temperatures of them show no significant difference. Particularly, 76.53% of the sodium in the feed coal has released to the gas phase after fluidized bed gasification. The chemical compositions of the semi-char are closely related to its particle size, attributable to the distinctly different natures of diverse elements. The semi-char exhibits a higher graphitization degree, higher BET surface area, and richer meso- and macropores, which results in superior gasification reactiv- ity than the coal char. The chemical reactivity of the semi-char is significantly improved by an increased gasifica- tion temperature, which suggests the necessity of regasification of the semi-char at a higher temperature. Conse- quently, it will be considered feasible that these carbons in the semi-char from fluidized bed gasitiers are rec- laimed and reused for the gasification process.

关键词： fluidized bed semi-char physicoehemical properties chemical compositions gasification reactivity

Surrogate atmospheric dust particles generated from dune soils in laboratory: Comparison with field measurement

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Particuology 2023年第1期72卷 29-36页

作者： Feng Wu Na Song Tafeng Hu Steven Sai Hang Ho Junji Cao Daizhou Zhang State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Key Laboratory of Aerosol Chemistry and Physics Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China CAS Center for Excellence in Quaternary Science and Global Change Xi’an710061China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing100029China Faculty of Environmental and Symbiotic Sciences Prefectural University of KumamotoKumamoto 862-8502Japan Division of Atmospheric Sciences Desert Research InstituteRenoNV 89512United States

Desert dust strongly influences the climate and the environment by altering the radiation budget, participating in atmospheric chemical reactions, and engaging the biogeochemical cycle. Studying its impacts requires knowledge of the physical and chemical properties of the original particles from the source origin. Unfortunately, the field collection of atmospheric samples in the desert is impractical. Fine surface soil is thus considered an alternative material from which to obtain the information applicable to dust particles from the desert soil. In this study, a laboratory system was set up to generate dust particles with simulated natural wind erosion processes from surface soils or directly from desert surfaces. Surface soils and field dust were simultaneously collected during a local blowing dust event. The comparison between the laboratory-generated dust and the field dust showed a consistent trend in particle size distribution and chemical composition. The chemical compositions were found to have explainable differences with the Certified Reference Materials for Asian dust (CJ-2). The laboratory-generated dust particles with the system could be applied as surrogates for soil-emitted dust in desert areas.

关键词： Laboratory dust simulation system Asian dust Source profiles Particle sizes chemical compositions