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Negatively and positively charged bacterial aerosol concentration and diversity in natural environments

Chinese Science Bulletin 2013年第26期58卷 3169-3176页

作者： SHEN FangXia KAI Wei YAO MaoSheng State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University

Bioaerosol charge information is of vital importance for their electrostatic collection. Here, electrostatic means and molecular tools were applied to studying bioaerosol charge dynamics. Positively or negatively charged bioaerosols were collected using an electrostatic sampler operated with a field strength of 1.1 kV cm 1 at a flow rate of 3 L min 1 for 40 min. Those with fewer or no charges bypassing the sampler were also collected using a filter at the downstream of the electrostatic sampler in one environment. The experiments were independently conducted three times in three different environments. The collected bacterial aerosols were cultured directly on agar plates at 26°C, and the colony forming units (CFU) were manually counted. In addition, the CFUs were washed off from the agar plates, and further subjected to polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) for culturable diversity analysis. The results revealed remarkable differences in positively and negatively charged culturable bacterial aerosol concentration and diversity among the studied environments. In the office environment, negatively charged culturable bacterial aerosols appeared to dominate (P = 0.0489), while in outdoor and hotel environments both polarities had similar concentration levels (P = 0.078, P = 0.88, respectively). DGGE patterns for positively charged culturable bacterial aerosols were shown strikingly different from those of negatively charged regardless of the sampling environments. In addition, for each of the environments positively charged culturable bacterial aerosols collected were found to have more band pattern similarity with those positively charged for respective regions of agar plates than those negatively charged, and vice versa. The information developed here is useful for developing efficient electrostatic sampling protocols for bioaerosols.

关键词：气溶胶浓度多样性分析办公环境正电荷细菌生物气溶胶变性梯度凝胶电泳静电收集

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environmental impact of radionuclide migration in groundwater from a low intermediate level radioactive waste repository

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Journal of environmental Sciences 2001年第2期13卷 180-184页

作者： J S Wang Z F Yang S S Li Z M Wang Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository environmental impact of radionuclide migration in groundwater from a low

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Synergetic PM_(2.5) and O_(3) control strategy for the Yangtze River Delta,China

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Journal of environmental Sciences 2023年第1期123卷 281-291页

作者： Zhaoxin Dong Jia Xing Fenfen Zhang Shuxiao Wang Dian Ding Hongli Wang Cheng Huang Haotian Zheng Yueqi Jiang Jiming Hao State Key Joint Laboratory of Environmental 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 Environmental Protection Key Laboratory of the Formation and Prevention of Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China

PM_(2.5)concentrations have dramatically reduced in key regions of China during the period 2013-2017,while O_(3)has *** there is an urgent demand to develop a synergetic regional PM_(2.5)and O_(3)control *** study develops an emission-to-concentration response surface model and proposes a synergetic pathway for PM_(2.5)and O_(3)control in the Yangtze River Delta(YRD)based on the framework of the Air Benefit and Cost and Attainment Assessment System(ABaCAS).Results suggest that the regional emissions of NOx,SO_(2),NH3,VOCs(volatile organic compounds)and primary PM_(2.5)should be reduced by 18%,23%,14%,17%and 33%compared with 2017 to achieve 25%and 5% decreases of PM_(2.5)and O_(3)in 2025,and that the emission reduction ratios will need to be 50%,26%,28%,28% and 55%to attain the National Ambient Air Quality *** effectively reduce the O_(3) pollution in the central and eastern YRD,VOCs controls need to be strengthened to reduce O_(3)by 5%,and then NOx reduction should be accelerated for air quality ***,control of primary PM_(2.5)emissions shall be prioritized to address the severe PM_(2.5)pollution in the northern *** most cities in the YRD,the VOCs emission reduction ratio should be higher than that for NOx in Spring and *** control should be increased in summer rather than winter when a strong VOC-limited regime ***,regarding the emission control of industrial processes,on-road vehicle and residential sources shall be prioritized and the joint control area should be enlarged to include Shandong,Jiangxi and Hubei Province for effective O_(3)control.

关键词： PM_(2.5) O_(3) Response surface model Synergistic control pathway Cost-benefit analysis

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Releasing characteristics of phosphorus and other substances during thermal treatment of excess sludge

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Journal of environmental Sciences 2007年第10期19卷 1153-1158页

作者： XUE Tao HUANG Xia Department of Environmental Science and Engineering State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua University Beijing 100084 China

The releasing characteristics of phosphorus, nitrogen compounds, organics, and some metal cations during thermal treatment of excess sludge were investigated. It was found that during heating not only phosphorus, but also nitrogen compounds, organics, and some metal cations could be released in abundance. The maximum orthophosphate （ortho-P） release of about 90 mg/L in concentration was observed at 50℃ in 1 h. Except for volatile fatty acids （VFAs）, comparatively little total nitrogen （TN）, total organic carbon （TOC）, and metal cations were released at the same time. Such results might favor further process of phosphorus recovery. VFAs were considerably released only at 50℃. Acetic, butyric, and propionic acid were the most abundant components in turn and their releasing profiles exhibited good linear relationship with time （R2 = 0.9977, 0.9624, and 0.8908, respectively）. The concentrations of Mg^2＋ and K^＋ increased with time and temperature during thermal treatment, but Ca^2＋ decreased. The release of Mg^2＋ and K^＋ agreed well with TP release （R^2 = 0.9892 and 0.9476, respectively）. Temperature in the experimental range had very little impact on the linear relationships, especially of Mg^2＋. Moreover, the parameter of mixed liquor suspended solids （MLSS） was found to be an important factor for thermal sludge treatment as the released ortho-P and total phosphorus （TP） at 50℃ increased more than one-fold when MLSS was increased from 4000 to 8000 mg/L.

关键词： phosphorus recovery excess sludge volatile fatty acids （VFAs） metal cations

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A review of atmospheric mercury emissions, pollution and control in China

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Frontiers of environmental Science & Engineering 2014年第5期8卷 631-649页

作者： Shuxiao WANG Lei ZHANG Long WANG Qingru WU FengyangWANG Jiming HAO State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084 China

Mercury, as a global pollutant, has significant impacts on the environment and human health. The current state of atmospheric mercury emissions, pollution and control in China is comprehensively reviewed in this paper. With about 500-800 t of anthropogenic mercury emissions, China contributes 25%-40% to the global mercury emissions. The dominant mercury emission sources in China are coal combustion, non-ferrous metal smelting, cement production and iron and steel production. The mercury emissions from natural sources in China are equivalent to the anthropogenic mercury emissions. The atmospheric mercury concentration in China is about 2-10 times the background level of North Hemisphere. The mercury deposition fluxes in remote areas in China are usually in the range of 10-50μg·m^-2·yr^-1. To reduce mercury emissions, legislations have been enacted for power plants, non-ferrous metal smelters and waste incinerators. Currently mercury contented in the flue gas is mainly removed through existing air pollution control devices for sulfur dioxide, nitrogen oxides, and particles. Dedicated mercury control technologies are required in the future to further mitigate the mercury emissions in China.

关键词： atmospheric mercury emissions pollution,control China

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Evaluation of the technoeconomic feasibility of electrochemical hydrogen peroxide production for decentralized water treatment

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Frontiers of environmental Science & Engineering 2021年第1期15卷 31-45页

作者： Yang Li Yixin Zhang Guangshen Xia Juhong Zhan Gang Yu Yujue Wang School of Environment State Key Joint Laboratory of Environmental Simulation and Pollution ControlBeijing Key Laboratory for Emerging Organic Contaminants ControlTsinghua UniversityBeijing 100084China

This study evaluated the feasibility of electrochemical hydrogen peroxide(H2O2)production with gas diffusion electrode(GDE)for decentralized water *** black-polytetrafluoroethylene GDEs were prepared and tested in a continuous flow electrochemical cell for H2O2 production from oxygen *** showed that because of the effective oxygen transfer in GDEs,the electrode maintained high apparent current efficiencies(ACEs,>80%)for H_(2)O_(2) production over a wide current density range of 5–400 mA/cm^(2),and H_(2)O_(2) production rates as high as~202 mg/h/cm^(2) could be ***-term stability test showed that the GDE maintained high ACEs(>85%)and low energy consumption(<10 kWh/kg H2O2)for H_(2)O_(2) production for 42 d(~1000 h).However,the ACEs then decreased to~70%in the following 4 days because water flooding of GDE pores considerably impeded oxygen transport at the late stage of the *** on an electrode lifetime of 46 days,the overall cost for H2O2 production was estimated to be~0.88$/kg H_(2)O_(2),including an electricity cost of 0.61$/kg and an electrode capital cost of 0.27$/*** a 9 cm^(2) GDE and 40 mA/cm^(2) current density,~2–4 mg/L of H2O2 could be produced on site for the electro-peroxone treatment of a 1.2 m^(3)/d groundwater flow,which considerably enhanced ibuprofen abatement compared with ozonation alone(~43%–59%vs.7%).These findings suggest that electrochemical H_(2)O_(2) production with GDEs holds great promise for the development of compact treatment technologies for decentralized water treatment at a household and community level.

关键词： Advanced oxidation process Electro-peroxone Gas diffusion electrode Hydrogen peroxide Oxygen reduction

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Perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs)in surface and tap water around Lake Taihu in China

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Frontiers of environmental Science & Engineering 2010年第3期4卷 301-310页

作者： Yong QIU He JING Hanchang SHI State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Perfluorinated compounds(PFCs)are ubiquitously distributed in the environment mainly as perfluorocarboxylic acids(PFCAs)and perfluoroalkyl sulfonates(PFASs).In this paper,six PFCAs and two PFASs were quantified in surface and tap water samples from 12 sites around Lake Taihu near Shanghai City in East *** PFCs were perfluorooctanoic acid(PFOA)and perfluorooctane sulfonate(PFOS),of which the concentration ranges were 6.8–206 and 1.2–45 ng·L^(–1),the geometric means were 35.3 and 9.4 ng·L^(–1),and the median(quartile range)values were 31.4(34.4)and 10.4(10.7)ng·L^(–1),*** PFCs were also detected but in much lower concentrations than *** sources of the PFCs were expected to be direct industrial discharges in the Lake Taihu area,and this area was also a possible source of PFCs contaminations in Shanghai district in the *** distributions were found different in the upstream,downstream and north part of Lake *** of PFCs in the tap water in Lake Taihu area indicated their exposure to the local people.A brief estimation of the environmental risks by PFCs implied no acute or immediate risks from PFCs to local human health,but chronic risks from PFOA in the tap water should be considered in the downstream regions.

关键词： surface and tap water perfluorocarboxylic acids(PFCAs) perfluoroalkyl sulfonates(PFASs) Lake Taihu area ultra performance liquid chromatography with tandem mass spectrometry(UPLC-MS)

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"Smoke Detector"of Human Diseases for environmental Aerosol Exposure

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Chinese Journal of Chemistry 2022年第12期40卷 1471-1477,I0002页

作者： Maosheng Yao State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Air consists of various different pollutants(both biological and non-biological).COVID-19 pandemic further threatens the air *** exposure causes many diseases including asthma,respiratory infections and *** protein bi-omarker for early diagnosis often fails due to its lower level at the very beginning of a *** another front,different technologies were attempted for realtime monitoring of air ***,many aerosol exposures occur silently without any knowledge due to limitation of available analytical *** breath has emerged as a promising non-invasive sample for disease diagnosis,in-cluding cancer and *** recently,it was shown that rats emitted distinc-tive profile of volatile organic compounds(VOCs)within minutes when exposed to different air pollutants including ozone and *** the pandemic times,breath-borne VOC was also used to rapidly screen *** exposure could result in changes in metabolism,thus releasing different pat-terns of VOCs via breath within very short *** monitoring of exhaled biomarker profile could spot the early signs of a disease,thus offering an earlier *** array and machine learning together can lend a great hand toward such an *** mini review is undertaken to share such endeavors and inspire further innovations.

关键词： Bioaerosol environmental aerosol exposure Breath biomarkerl Disease Detection Analytical Sensor

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Recent advances in membrane bioreactor technology for wastewater treatment in China

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Frontiers of environmental Science & Engineering 2010年第3期4卷 245-271页

作者： Xia HUANG Kang XIAO Yuexiao SHEN State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Since the introduction of the membrane bioreactor(MBR)in China in the early 1990s,remarkable progress has been achieved on the research and application of this *** has now become one of the most active fields in the world in this *** review outlines the development of MBR-based processes in China and their performance of treating municipal and industrial *** membrane fouling is a critical operational problem with MBR processes,this paper also proposes updated understanding of fouling mechanisms and strategies of fouling control,which are mainly compiled from publications of Chinese *** for the commercial application of MBR in the country,the latest statistics of large-scale MBR plants(>10000 m^(3)·d^(–1))are provided,and the growth trend of total treatment capacity as well as its driving force is analyzed.

关键词： membrane bioreactor(MBR) municipal wastewater treatment industrial wastewater treatment membrane fouling commercial application China

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Efficient photocatalytic reduction of chromium(Ⅵ) using photoreduced graphene oxide as photocatalyst under visible light irradiation

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Journal of Materials Science & Technology 2021年第32期91卷 17-27页

作者： Mei Yu Jing Shang Yu Kuang Department of Environment and Health State Key Joint Laboratory of Environmental Simulation and Pollution ControlCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

Graphene oxide(GO),a new and promising material,has been widely used as a co-catalyst in photocatalytic reactions;however,its capacity as a sole photocatalyst has rarely been *** this study,ultraviolet(UV) light irradiation was used as a modification method to obtain reduced GO(rGO) *** samples were used as photocatalysts to examine their visible light photocatalytic activity toward hexavalent chromium(Cr(Ⅵ)) *** force microscopy(AFM),X-ray diffraction(XRD),UV-vis spectrophotometry,Raman spectroscopy,X-ray photoelectron spectroscopy(XPS),and electron spin resonance(ESR) spectroscopy were applied to interpret the surface and structure changes with UV *** oxygen-containing functional groups(OFGs) on the GO surface were reduced to defective carbons andπ-conjugated C=C(sp^(2) domains) under UV light;this led to a decrease in the interlayer distance between GO sheets,GO fragmentation,and increased disorder on the GO *** restoration of sp^(2) domains led to a narrower band gap of GO,which favored the rGO excitation by visible light to generate electron-hole *** rGO pre-irradiated with UV for 1 h(rGO-1),possessing the highest defect density and electron generation efficiency,exhibited the best Cr(Ⅵ) reduction efficiency,which was about three times that of the GO sample;moreover,it outperformed most of the reported GO-based *** addition,low pH and the addition of citric acid as a hole scavenger could further improve the photocatalytic *** study proves that GO or rGO can be used as a sole photocatalyst under visible light to remove environmental pollutants such as heavy-metal ions,and it paves the way for the development of this kind of material and its UV-irradiation modification for further applications.

关键词： Graphene oxide Chromium(Ⅵ) Defect density UV-irradiation modification Photocatalytic reduction

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