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Individual particle analysis of aerosols collected at Lhasa City in the Tibetan Plateau

Journal of environmental Sciences 2015年第3期27卷 165-177页

作者： Bu Duo Yunchen Zhang Lingdong Kong Hongbo Fu Yunjie Hu Jianmin Chen Lin Li A.Qiong Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science & EngineeringFudan University Department of Chemistry & environmental Science Tibet University environmental monitoring center Station of Tibet Autonomous Region

To understand the composition and major sources of aerosol particles in Lhasa City on the Tibetan Plateau （TP）, individual particles were collected from 2 February to 8 March, 2013 in Tibet University. The mean concentrations of both PM2.5 and PM10 during the sampling were 25.7 ± 21.7 and 57.2 ± 46.7 μg/m^3, respectively, much lower than those of other cities in East and South Asia, but higher than those in the remote region in TP like Nam Co, indicating minor urban pollution. Combining the observations with the meteorological parameters and back trajectory analysis, it was concluded that local sources controlled the pollution during the sampling. Transmission electron microscopy （TEM） combined with energydispersive X-ray spectra （EDS） was used to study 408 particles sampled on four days. Based on the EDS analysis, a total of 8 different particle categories were classified for all 408 particles, including Si-rich, Ca-rich, soot, K-rich, Fe-rich, Pb-rich, Al-rich and other particles. The dominant elements were Si, A1 and Ca, which were mainly attributed to mineral dust in the earth＇s crust such as feldspar and clay. Fe-, Pb-, K-, Al-rich particles and soot mainly originated from anthropogenic sources like firework combustion and biomass burning during the sampling. During the sampling, the pollution mainly came from mineral dust, while the celebration ceremony and religious ritual produced a large quantity of anthro- pogenic metal-bearing particles on 9 and 25 February 2013. Cement particles also had a minor influence. The data obtained in this study can be useful for developing pollution control strategies.

关键词： Individual particles Fireworks Biomass burning Lhasa TEM

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Water quality characteristics along the course of the Huangpu River (China)

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Journal of environmental Sciences 2007年第10期19卷 1193-1198页

作者： YANG Hong-jun SHEN Zhe-min ZHANG Jin-ping WANG Wen-hua School of environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Xuhui District environmental Protection Bureau Shanghai 200030 China Shanghai environmental monitoring center Shanghai 200030 China

Huangpu River is about 114.5 km from upriver Dianfeng to downriver Wusong, near the estuary of the Yangtze River. It plays a key role in supplying water for production, life, shipment and irrigation. With the industrial development, the pollution of the Huangpu River has become serious recently. The biological oxygen demand （BOD）, total nitrogen （TN）, total phosphorus （TP）, oil, phenol and suspended solids （SS） were lower in the upstream sites than in the downstream sites, indicating pollutants being input along its course. Water quality was the worst in the Yangpu site, near the center of Shanghai City. Dissolved oxygen （DO） content was less than 2 mg/L in the site of Yangpu in July. Among relations between thirteen characteristics, relations between BOD, DO, TN, TP, NH4^＋ -N, NO3^- -N and the count of total bacteria or Escherichia coli were significant and interdependent. Inner relationships between these main characteristics in the Huangpu River were studied. High nutrient concentration led to growth of microorganisms, including E. coli. Degradation of organic matters and respiration of bacteria made oxygen concentration decreased in the water body, and DO was a key factor for nitrification-denitrification process of nitrogen. In the Yangpu site, DO was decreased to less than 3.0 mg/L with BOD higher than 7.5 mg/L in May and July. Low DO concentration will decrease nitrification rate. Nitrification need at higher DO value than other organic substrate oxidation. Consequently, river water contains low NO3^- -N values with high amounts of TN and NH4^＋ -N there. This will block the self-purification of surface water, by decreasing the rate of nitrification-denitrification transformation process in the water body.

关键词： water quality ecological assessment Huangpu River nitrification

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Molecular Simulation of Naphthenic Acid Removal on Acidic Catalyst(I) Mechanism of Catalytic Decarboxylation

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China Petroleum Processing & Petrochemical Technology 2008年第1期10卷 49-54页

作者： Fu Xiaoqin Dai Zhenyu Tian Songbai Hou Suandi Wang Xieqing (1 Ningbo environmental monitoring center, Ningbo 315012 2 Research Institute of Petroleum Processing , Beijing 100083) Ningbo environmental monitoring center Ningbo 315012 Research Institute of Petroleum Processing Beijing 100083

In this paper, the charge distribution, the chemical bond order and the reactive performance of carboxylic acid model compounds on acidic catalyst were investigated by using molecular simulation technology. The simulation results showed that the bond order of C—O was higher than that of C—C, and C—C bond connected to the carbon atom in the carboxyl radical had the lowest bond order. The charge distributions of model naphthenic acids were similar in characteristics that the negative charges were concentrated on carboxyls. According to the simulation results, the mechanisms of catalytic decar- boxylation over acidic solid catalyst were proposed, and a new route was put forward regarding removal of the naphthenic acid from crude oil through catalytic decarboxylation.

关键词： naphthenic acid catalytic decarboxylation molecular simulation mechanism

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Diagnostic model construction and example analysis of habitat degradation in enclosed bay: I. diagnostic model construction

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Chinese Journal of Oceanology and Limnology 2014年第3期32卷 626-635页

作者：于格孙芃刘光兴徐东晖丁光茂黄东仁 Key Laboratory of Marine environmental Science and Ecology College of Environmental Sciences and EngineeringOcean University of China Fujian Provincial Ocean and Fisheries monitoring center

Presently, research is lacking regarding the diagnosis and evaluation of habitat degradation in enclosed bay systems. We established a diagnostic model for enclosed bay habitat degradation(EBHD model) using a multi-approach integrated diagnostic method in consideration of driving force-pressurestate-infl uence-response. The model optimizes the indicator standardization with annual average change rate of habitat degradation as the basic element, to refl ect accurately the impact of the change and speed of degradation on the diagnostic results, to quantify reasonably the contribution of individual diagnostic indicator to habitat degradation, and to solve the issue regarding the infl uence of subjective factors on the evaluation results during indicator scoring. We then applied the EBHD model for the Sansha Bay in Fujian Province, China, evaluated comprehensively the situation of habitat degradation in the bay, and screened out the major controlling factors in the study area. Results show that the diagnostic results are consistent in overall with the real situation of the study area. Therefore, the EBHD model is advantageous in terms of objectivity and accuracy, making a breakthrough in diagnosis and evaluation for habitat degradation in enclosed bay systems.

关键词： enclosed bay habitat degradation diagnostic model Sansha Bay

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Selective separation of polychlorinated naphthalene (PCNs), hexabromocyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA) in soil matrices

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Chinese Science Bulletin 2013年第4期58卷 500-506页

作者： TENG Man JIN Jing FU Qiang CAI YaQi CHEN JiPing WEI FuSheng Research center for Eco-environmental Sciences Chinese Academy of Sciences China National environmental monitoring center Dalian Institute of Chemical Physics Chinese Academy of Sciences

A method for the selective separation of polychlorinated naphthalene (PCNs), hexabromocyclododecanes (HBCDs) and tetrabro-mobisphenol A (TBBPA) in complex matrices was developed. In the present study, the type of sorbents and the volume and composition of eluting solvents were investigated in detail. Under the optimal conditions, the recoveries of PCNs, HBCDs and TBBPA in different fractions were determined with liquid/gas chromatography tandem mass spectrometry (LC or GC-MS/MS), which was nearly close to 100%. To investigate the feasibility of the developed method, it was applied to isolate target compounds from spiked soil extracts. PCNs, HBCDs and TBBPA could be subsequently eluted with hexane, hexane/dichloromethane (1:1), and hexane/dichloromethane (1:3), and the recoveries of the analysts from three fractions were satisfactory (70.9%-107%) with the exception of -HBCD at low levels. The results indicated that the method exhibited good performance for the selective separation of PCNs, HBCDs and TBBPA and showed great potential in sample pretreatment in terms of alleviating influence from different class of impurities to some extent.

关键词：选择性分离四溴双酚A 矩阵A 氯化土壤四溴双酚-A 六溴环十二烷萘

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Molecular Simulation of Naphthenic Acid Removal on Acidic Catalyst II. Experimental results of catalytic decarboxylation over acidic catalysts

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China Petroleum Processing & Petrochemical Technology 2008年第2期10卷 29-33页

作者： Fu Xiaoqin Tian Songbai Hou Shuandi Longjun Wang Xieqing Ningbo environmental monitoring center Ningbo Research Institute of Petroleum Processing Beijing 100083

The energy barriers of thermal decarboxylation reactions of petroleum acids and catalytic decarboxylation reactions of Bronsted acid and Lewis acid were analyzed using molecular simulation technology. Compared with thermal decarboxylation reactions of petroleum acids, the decarboxylation reactions by acid catalysts were easier to occur. The decarboxylaton effect by Lewis acid was better than Bronsted acid. The mechanisms of catalytic decarboxylation over acid catalyst were also verified by experiments on a fixed bed and a fluidized bed, the experimental results showed that the rate of acid removal could reach up to 97% over the acidic catalyst at a temperature above 400℃.

关键词： petroleum acids naphthenic acid catalytic decarboxylation molecular simulation solid acidcatalyst

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Agricultural non-point nitrogen pollution control function of dierent vegetation types in riparian wetlands: A case study in the Yellow River wetland in China

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Journal of environmental Sciences 2009年第7期21卷 933-939页

作者： ZHAO Tongqian XU Huashan HE Yuxiao TAI Chao MENG Hongqi ZENG Fanfu XING Menglin Institute of Resources and Environment Henan Polytechnic University Jiaozuo 454003 China Henan Province environmental monitoring center Zhengzhou 450004 China

Riparian wetland is the major transition zone of matter, energy and information transfer between aquatic and terrestrial ecosystems and has important functions of water purification and non-point pollution control. Using the field experiment method and an isotope tracing technique, the agricultural non-point nitrogen pollution control function of different vegetation types in riparian wetland was studied in the Kouma Section of the Yellow River. The results showed that the retention of agricultural non-point nitrogen pollution by riparian wetland soil occurs mainly in top 0-10 cm layer. The amount of nitrogen retained by surface soils associated with three types of vegetation are 0.045 mg/g for Phragmites communis Trin Linn, 0.036 mg/g for Scirpus triqueter Linn, and 0.032 mg/g for Typha angustifolia Linn, which account for 59.21%, 56.25%, and 56.14% of the total nitrogen interception, respectively. Exogenous nitrogen in 0-10 cm soil layer changes more quickly than in other layers. One month after adding KISNO3 to the tested vegetation, nitrogen content was 77.78% for P communis Trin, 68.75% for T. angustifolia, and 8.33% for S. triqueter in the surface soil. After three months, nitrogen content was 93.33% for P. communis Trin, 72.22% for S. triqueter, and 37.50% for T. Angustifolia. There are large differences among vegetation communities respecting to purification of agricultural non-point nitrogen pollution. The nitrogen uptake amount decreases in the sequence： new shoots ofP. communis Trin （9.731 nag/g）〉 old P. communis Trin （4.939 mg/g）〉 S. triqueter （0.620 mg/g）〉 T. angustifolia （0.186 mg/g）. Observations indicated that the presence of riparian wetlands as buffers on and adjacent to stream banks could be recommended to control agricultural non-point pollution.

关键词： riparian wetland vegetation community agricultural non-point source nitrogen pollution

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Biosynthesized CS-MgO/zeolite hybrid material:An efficient adsorbent for chlorpyrifos removal-Kinetic studies and response surface methodology

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Emerging Contaminants 2024年第3期10卷 304-317页

作者： Mohammed T.M.H.Hamad Belal N.A.Mahran Central Laboratory for environmental Quality monitoring National Water Research CenterEgypt

The prevalence of organophosphate pesticides in aquatic environments raises severe concerns on a global ***,an insecticide,is included in a class of organophosphate *** is widely used on agricultural lands to control pests in cotton,fruit,and *** acute toxicity of chlorpyrifos is still dangerous to all aquatic living *** the treatment of water contaminated with chlorpyrifos is an important *** recent decade has witnessed adsorption technology emerging as an advanced organophosphate pesticide wastewater treatment with great potential and a grand blueprint,in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption *** this study,a CS-MgO/Zeolite composite was prepared by the microbial method as an effective adsorbent for the removal of chlorpyrifos from an aqueous *** adsorbent's properties were carefully characterized using Xray diffraction,scanning electron microscopy,and Fourier-transform infrared *** refinement of experimental conditions,encompassing variations in adsorbent dosage,contact time,and chlorpyrifos concentration at five discrete levels,was systematically undertaken through the utilization of a composite central design rooted in response surface *** solution pH played a key role in chlorpyrifos removal,and a pH of 7.0 was selected according to its high adsorption *** highest removal(80.9%)of chlorpyrifos by CS-MgO/Zeolite was obtained at an optimum pH of 7,a contact time of 40 min,an adsorbent dosage of 0.4 g/L,and a chlorpyrifos concentration of 5 mg/L^(-1).The adsorption results were highly fitted with the Freundlich adsorption isotherm model,and the maximum adsorption was 83.3 mg/*** studies indicate that the removal of chlorpyrifos followed the pseudo-secondorder model of adsorption(0.994).The thermodynamic parameters indicate the sponta

关键词： Chlorpyrifos adsorption CS-MgO/Zeolite Response surface methodology

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Morphology of single inhalable particle in the air polluted city of Shijiazhuang,China

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Journal of environmental Sciences 2008年第4期20卷 429-435页

作者： WANG Zanhong ZHANG Lingzhi ZHANG Yuliang ZHAO Zhou ZHANG Sumin College of Resource and Environment Sciences Hebei Normal University Shijiazhuang 050016 China environmental monitoring center of Shifiazhuang Shijiazhuang 050016 China

In the typical air polluted city of Shijiazhuang, single inhalable particle samples in non-heating period, heating period, dust storm days, and snowy days were collected and detected by SEM/EDS （scanning electron microscopy and energy dispersive X-ray spectrometry）. The particle morphology was characterized by the 6 shape clusters, which are： irregular square, agglomerate, sphere, floccule, column or stick, and unknown, by quantitative order. The irregular square particles are common in all kinds of samples; sphere particles are more, and column or stick are less in winter samples; in the wet deposit samples, agglomerate and floccule particles are not found. The surface of most particles is coarse with fractal edge, which can provide suitable chemical reaction bed in the polluted atmospheric environment. New formed calcium crystal is found to demonstrate the existence of neutralized reaction, explaining the reason for the high SO2 emission and low acid rain frequency in Shijiazhuang. The three sorts of surface patterns of spheres are smooth, semi-smooth, and coarse, corresponding to the element of Si-dominant, Si-Al-dominant, and Fe-dominant, The soot particle is present as floccule with average size around 10 μm, considerably larger than the former reported results, but wrapped or captured with other fine particles to make its appearance unique and enhance its toxicity potentially. The new formed calcium crystal, the 3 sorts of sphere surface patterns, and the unique soot appearance represent the single inhalable particle＇s morphology characteristics in Shijiazhuang City.

关键词： single particle morphology new formed calcium crystal spheres soot

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The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

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Journal of environmental Sciences 2019年第5期31卷 121-134页

作者： Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu Research center for Eco-environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Shenyang Academy of environmental Sciences Shenyang environmental monitoring Centre Chinese Research Academy of environmental Sciences

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang.

关键词： Volatile organic compounds Source apportionment Photochemical ozone formation Field measurement

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