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Journal of environmental Sciences 2019年第1期31卷 388-395页

作者： Zhenli Sun Fengkui Duan Kebin He Jingjing Du Liu Yang Hui Li Tao Ma Shuo Yang state key joint laboratory of environment simulation and pollution control School of Environment Tsinghua University state environmental Protection key laboratory of Sources and control of Air pollution Complex Tsinghua University state key laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Fine particles associated with haze pollution threaten the health of more than 400 million people in China. It is therefore of great importance to thoroughly investigate and understand their composition. To determine the physicochemical properties in atmospheric fine particles at the micrometer level, we described a sensitive and feasible surface-enhanced Raman scattering(SERS) method using Ag foil as a substrate. This novel method enhanced the Raman signal intensities up to 10,000 a.u. for ν(NO_3^-) in fine *** SERS effect of Ag foil was further studied experimentally and theoretically and found to have an enhancement factor of the order of ～10~4. Size-fractionated real particle samples with aerodynamic diameters of 0.4–2.5 μm were successfully collected on a heavy haze day,allowing ready observation of morphology and identification of chemical components, such as soot, nitrates, and sulfates. These results suggest that the Ag-foil-based SERS technique can be effectively used to determine the microscopic characteristics of individual fine particles, which will help to understand haze formation mechanisms and formulate governance policies.

关键词： SERS PM2.5 Individual particle Atmospheric

Realizing stable operation of anaerobic ammonia oxidation at low temperatures treating low strength synthetic wastewater

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Journal of environmental Sciences 2019年第1期31卷 193-200页

作者： Bowen Zhang Jian Zhao Jiane Zuo Xuchuan Shi Jiayi Gong Haiteng Ren state key joint laboratory of environment simulation and pollution control School of Environment Tsinghua University Beijing Enterprises Water Group Limited SUEZ NWS Company Limited

The low activity of Anammox bacteria at low temperatures and competition from nitrite oxidation bacteria(NOB) when treating low strength wastewater have been major bottlenecks in implementing Anammox in mainstream wastewater treatment. By intermittent high strength feeding(IHSF) and stepwise temperature reduction, stable operation of a granular Anammox reactor was realized at low temperatures(down to 15°C) for 28 days when treating low strength synthetic wastewater. The nitrogen loading rate reached 1.23–1.34 kgN/m^3/day,and the total nitrogen removal rate reached 0.71–0.98 kgN/m^3/day. The IHSF enriched the Anammox sludge in high strength cycles and compensated for sludge loss in low strength cycles, and the high concentration of ammonium in high strength cycles inhibited NOB. The 16 SrRNA gene sequencing results revealed that Candidatus Kuenenia was predominant in the reactor at low temperatures.

关键词： Biological nitrogen removal Low temperature Granular Anammox SBR Microbial community

Application of internal standard method in recombinant luminescent bacteria test

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Journal of environmental Sciences 2015年第9期27卷 128-134页

作者： Yong-zhi Wang Dan Li Miao He environmental simulation and pollution control (ESPC) state key joint laboratory School of Environment Tsinghua University Fudan University Department of Environmental Science & Engineering

Mercury and its organic compounds have been of severe concern worldwide due to their damage to the ecosystem and human health. The development of effective and affordable technology to monitor and signal the presence of bioavailable mercury is an urgent *** Mer gene is a mercury-responsive resistant gene, and a mercury-sensing recombinant luminescent bacterium using the Mer gene was constructed in this study. The mer operon from marine Pseudomonas putida strain SP1 was amplified and fused with prompterless lux CDABE in the p UCD615 plasmid within Escherichia coli cells, resulting in p THE30–E. *** recombinant strain showed high sensitivity and specificity. The detection limit of Hg^2＋was 5 nmol/L, and distinct luminescence could be detected in 30 min. Cd^2＋, Cu^2＋, Zn^2＋, Ca^2＋,Pb^2＋, Mg^2＋, Mn^2＋, and Al^3＋did not interfere with the detection over a range of 10-5–1 m *** of recombinant luminescent bacteria testing in environmental samples has been a controversial issue： especially for metal-sensing recombinant strains, false negatives caused by high cytotoxicity are one of the most important issues when applying recombinant luminescent bacteria in biomonitoring of heavy metals. In this study, by establishing an internal standard approach, the false negative problem was overcome;furthermore, the method can also help to estimate the suspected mercury concentration,which ensures high detection sensitivity of bioavailable Hg2＋.

关键词： Mercury Biomonitoring Recombinant luminescent bacteria p THE30–E.coli Internal standard method False negative

Microbial aerosol chemistry characteristics in highly polluted air

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Science China Chemistry 2019年第8期62卷 1051-1063页

作者： Ting Zhang Xinyue Li Minfei Wang Haoxuan Chen Maosheng Yao state key joint laboratory of environmental simulation and pollution control College of Environmental Sciences and EngineeringPeking University

Aerosol chemistry is often studied without considering microbial involvements. Here, we investigated time-and size-resolved bacterial aerosol dynamics in air. Under high particulate matter(PM) polluted episodes, bacterial aerosols exhibited a viability of up to 50%–70% in the 0.56–1 μm size range, at which elevated levels of SO42-, NO3- and NH4+ were concurrently *** or acclimated for both industrial use, bacteria such as Psychrobacter spp., Massilia spp., Acinetobacter lwoffii,Exiguobacteriumaurantiacum and Bacillusmegaterium were shown to have experienced massive abundance shifts in polluted air on early mornings and late afternoons, on which rapid new particle formation events were widely reported. Here, Psychrobacter spp. were shown to account for >96% abundance at a corresponding PM2.5 level of 208 μg/m3. These observed bacterial aerosol changes corresponded to the PM2.5 mass peak shift from 3.2–5.6 μm to the high viability size range of 0.56–1 μm. Additionally,elevated levels of soluble Na, Ca, Mg, K, Al, Fe and P elements, required for bacterial growth, were observed to co-occur with those significant bacterial aerosol structure shifts in the air. For particular time-resolved PM2.5 pollution episodes, Acinetobacter,Psychrobacter and Massilia were shown to alternate in dominating the time-resolved aerosol community structures. The results from a HYSPLIT trajectory model simulation suggested that air mass transport played a minor role in affecting the observed bacterial aerosol structure dynamics. All the data here suggested that airborne bacteria in the size range of 0.56–1 μm could be extensively involved in aerosol chemistry in highly polluted humid air.

关键词： bacterial aerosol dynamics in air particulate matter size-and time-resolved bacterial aerosol aerosol chemistry

Spatial and temporal variation of haze in China from 1961 to 2012

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Journal of environmental Sciences 2016年第8期28卷 134-146页

作者： Rui Han Shuxiao Wang Wenhai Shen Jiandong Wang Kang Wu Zhihua Ren Mingnong Feng National Meteorological Information Center China Meteorological Administration state key joint laboratory of environment simulation and pollution control School of Environment Tsinghua University state environmental Protection key laboratory of Sources and control of Air pollution Complex Department of Precision Instrument Tsinghua University

The purpose of this study is to analyze the climatic characteristics and long-term spatial and temporal variations of haze occurrence in China. The impact factors of haze trends are also discussed. Meteorological data from 1961 to 2012 and daily PM10 concentrations from2003 to 2012 were employed in this study. The results indicate that the annual-average hazy days at all stations have been increasing rapidly from 4 days in 1961 to 18 days in 2012. The maximum number of haze days occur in winter（41.1%） while the minimum occur in summer（10.4%）. During 1961-2012, the high occurrence areas of haze shifted from central to south and east regions of China. The Beijing-Tianjin-Hebei（Jing-Jin-Ji） region, Shanxi,Shaanxi, and Henan Province are the high occurrence areas for haze, while the Yangtze River Delta（YRD） and the Pearl River Delta（PRD） have become regions with high haze occurrences in the last 25 years. Temperature and pressure are positively correlated with the number of haze days. However, wind, relative humidity, precipitation, and sunshine duration are negatively correlated with the number of haze days. The key meteorological factors affecting the formation and dissipation of haze vary for high and low altitudes, and are closely related to anthropogenic activities. In recent years, anthropogenic activities have played a more important role in haze occurrences compared with meteorological factors.

关键词： China Haze Spatial distribution Interannual trend Meteorological factors Anthropogenic activities

Evolution of soil DOM during thermal remediation below 100℃:concentration,spectral characteristics and complexation ability

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Frontiers of environmental Science & Engineering 2024年第8期18卷 31-41页

作者： Wan Huang Ziren Wan Di Zheng Lifeng Cao Guanghe Li Fang Zhang state key joint laboratory of environment simulation and pollution control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China National Engineering laboratory for Site Remediation Technologies Beijing 100015China

The impact of thermal remediation on soil function has drawn increasing *** far,as the most active fraction of soil organic matter,the evolution of dissolved organic matter(DOM)during the thermal remediation lacks in-depth investigation,especially for the temperatures value below 100℃.In this study,a series of soil thermal treatment experiments was conducted at 30,60,and 90℃ during a 90-d period,where soil DOM concentration increased with heating temperature and *** molecular weight,functional groups content and aromaticity of DOM all decreased during the thermal *** excitation-emission matrices(EEM)results suggested that humic acid-like substances transformed into fulvic acid-like substances(FIII/FV increased from 0.27 to 0.44)during the heating process,and five DOM components were further identified by *** change of DOM structures and components indicated the decline of DOM stability and hydrophilicity,and can potentially change the bioavailability and *** temperature also resulted in the decline of DOM complexation ability,which may be caused by the loss of binding sites due to the decrease of polar function groups,aromatic structures and hydrophilic *** study provides valuable information about the evolution of DOM during thermal remediation,which would potentially change the fate of metal ions and the effectiveness of the post-treatment technologies in the treated region.

关键词： Thermal remediation below 100℃ Heating temperature Soil DOM concentration DOM spectral characteristics Excitation-emission matrices(EEM) Complexation ability

Characteristics of volatile organic compounds,NO_2,and effects on ozone formation at a site with high ozone level in Chengdu

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Journal of environmental Sciences 2019年第1期31卷 334-345页

作者： Yuanyuan Deng Jing Li Yaqi Li Rongrong Wu Shaodong Xie College of environmental Sciences and Engineering State Key Joint Laboratory of Environmental Simulation and Pollution ControlPeking University

Chengdu is a megacity in the southwest of China with high ozone(O_3) mixing *** of volatile organic compounds(VOCs), NO_2 and O_3 with high temporal resolution was conducted in Chengdu to investigate the chemical processes and causes of high O_3 levels. The hourly mixing ratios of VOCs, NO2, and O_3 were monitored by an online system from 28 August to 7 October, 2016. According to meteorological conditions,Chengdu, with relative warm weather and low wind speed, is favorable to O_3 *** of the O_3 in Chengdu may be transported from the downtown area. In O_3 episodes,the average mixing ratios of NO_2 and O_3 were 20.20 ppbv and 47.95 ppbv, respectively. In non-O_3 episodes, the average mixing ratios of NO_2 and O_3 were 16.38 ppbv and 35.15 ppbv,respectively. The average mixing ratio of total VOCs(TVOCs) was 40.29 ppbv in non-O_3 episodes, which was lower than that in O_3 episodes(53.19 ppbv). Alkenes comprised51.7% of the total O_3 formation potential(OFP) in Chengdu, followed by aromatics which accounted for 24.2%. Ethylene, trans-pentene, propene, and BTEX(benzene, ethylbenzene,toluene, m/p-xylene, o-xylene) were also major contributors to the OFP in Chengdu. In O_3 episodes, intensive secondary formations were observed during the campaign. Oxygenated VOCs(OVOCs), such as acetone, Methylethylketone(MEK), and Methylvinylketone(MVK)were abundant. Isoprene rapidly converted to MVK and Methacrolein(MACR) during O_3 episodes. Acetone was mainly the oxidant of C3-C5 hydrocarbons.

关键词： Ozone formation VOCs NO2 OFP Diurnal variation

Estimating emissions from crop residue open burning in China based on statistics and MODIS fire products

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Journal of environmental Sciences 2016年第6期28卷 158-170页

作者： Jing Li Yu Bo Shaodong Xie College of environmental Sciences and Engineering State Key Joint Laboratory of Environmental Simulation and Pollution ControlPeking University

With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer（MODIS） Thermal Anomalies/Fire Daily Level3 Global Product（MOD/MYD14A1）. Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO2, CO, CH4,nonmethane volatile organic compounds（NMVOCs）, N2O, NOx, NH3, SO2, fine particles（PM2.5）,organic carbon（OC）, and black carbon（BC） were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June（37%）.Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N2O to a high of within ± 169% for NH3.

关键词： Crop residue open burning Air quality Emission inventory Moderate resolution imaging spectroradiometer(MODIS)

Chemical characteristics and sources of water-soluble organic aerosol in southwest suburb of Beijing

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Journal of environmental Sciences 2020年第9期32卷 99-110页

作者： Ruolan Hu Qingcheng Xu Shuxiao Wang Yang Hua Noshan Bhattarai Jingkun Jiang Yu Song Kaspar R.Daellenbach Lu Qi Andre S.H.Prevot Jiming Hao state key joint laboratory of environment simulation and pollution control School of EnvironmentTsinghua UniversityBeijing 100084China state environmental Protection key laboratory of Sources and control of Air pollution Complex Beijing 100084China state key joint laboratory of environment simulation and pollution control Department of Environmental SciencePeking UniversityBeijing 100871China laboratory of Atmospheric Chemistry Paul Scherrer Institute5232 VilligenSwitzerland Institute for Atmospheric and Earth System Research University of HelsinkiFinland

PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site(referred herein as "LLH site") located in the southwest of *** offline aerosol mass spectrometry(offline-AMS) analysis and positive matrix factorization(PMF) were applied for measurement and source apportionment of watersoluble organic aerosol(WSOA).Organic aerosol(OA) always dominated PM2.5 during the sampling period,especially in *** pollution was serious during the polluted period both in autumn(31.1 μg/m3) and winter(31.9 μg/m3),while WSOA accounted for 54.4%of OA during the polluted period in autumn,much more than that(21.3%) in *** oxidation degree of WSOA at LLH site was at a high level(oxygen-to-carbon ratio,O/C=0.91)and secondary organic aerosol(SOA) contributed more mass ratio of WSOA than primary organic aerosol(POA) during the whole observation *** winter,coal combustion OA(CCOA) was a stable source of OA and on average accounted for 25.1% of *** autumn,biomass burning OA(BBOA) from household combustion contributed 38.3% of WSOA during polluted *** addition to oxygenated OA(OOA),aqueous-oxygenated OA(aq-OOA) was identified as an important factor of *** heavy pollution period,the mass proportion of aq-OOA to WSOA increased significantly,implying the significant SOA formation through aqueous-phase *** result of this study highlights the concentration on controlling the residential coal and biomass burning,as well as the research needs on aqueous chemistry in OA formation.

关键词： pollution aerosol winter

Fabrication of TiO_2 Nanotube Arrays by Rectified Alternating Current Anodization

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Journal of Materials Science & Technology 2015年第1期31卷 23-29页

作者： Han Song Jing Shang Chen Suo state key joint laboratory of environmental simulation and pollution control College of Environmental Sciences and EngineeringPeking University

Anodization is a popular method of preparing TiO2nanotube array films（TiNTs） by using direct current（DC）power as the driving *** this study,three driving voltage modes,namely,the sine alternating current（sine） mode,the full-wave rectification of sine waves via four diodes（sine-4D,where D means diode） mode,and the DC mode,were used to prepare TiNTs by *** 20 V,TiNTs were formed under sine-4D mode but only irregular porous TiO2films were formed under DC *** 50 V,TiNTs formed under both the sine-4D and DC *** TiNTs formed in the sine mode anodization at either 20 or 50 *** with the DC mode,the sine-4D mode required a lower oxidation voltage for TiNT formation,which suggests that sine-4D is an economical,convenient,and efficient driving voltage for TiNT preparation by *** morphologies and structures of TiNT samples anodized at 50 V in the sine-4D and DC modes at different oxidation time（1,5,10,30,60,and 120 min） were *** growth processes were similar between the studied ***,the growth rate of the films was faster under the sine-4D mode than the DC mode during the first 30 min of anodization.

关键词： TiO2nanotube Anodization Alternating current Growt