Functions and behaviors of activated sludge extracellular polymeric substances (EPS): a promising environmental interest

Extracellular polymeric substances （EPS） are the predominant constituents of activated sludge and represent up to 80% of the mass of activated sludge. They play a crucial role in the flocculation, settling and dewatering of activated sludge. Furthermore, EPS also show great efficiency in binding heavy metals. So EPS are key factors influencing reduction in sludge volume and mass, as well as activity and utilization of sludge. EPS are of considerable environmental interest and hundreds of articles on EPS have been published abroad, while information on EPS in China is limited. In this paper, results of over 60 publications related to constituents and characteristics of EPS and their influences on flocculation, settling and dewatering of sludge are compiled and analyzed. Metal-binding ability of EPS is also discussed, together with a brief consideration of possible research interests in the future.

Investigates of substrate mingling ratio and organic loading rate of KOH pretreated corn stover and pig manure in batch and semi-continuous system:Anaerobic digestion performance and microbial characteristics

The effects of substrate mingling ratio(SMR)(1:1,1:2,1:3,3:1,and 2:1)and organic loading rate(OLR)(50-90 g total solids per liter per day)on anaerobic co-digestion performance and microbial characteristics were investigated for pig manure(PM)and pretreated/untreated corn stover in batch and semicontinuous anaerobic digestion(AD)system.The results showed that SMR and pretreatment affected co-digestion performance.The maximum cumulative methane yield of 428.5 ml·g^(-1)(based on volatile solids(VS))was obtained for PCP13,which was 35.7%and 40.0%higher than that of CSU and PM.In the first 5 days,the maximum methane yield improvement rate was 378.1%for PCP13.The daily methane yield per gram VS of PCP13 was 11.4%-18.5%higher than that of PC_(U)13.Clostridium_sensu_stricto_1,DMER64,and Bacteroides and Methanosaeta,Methanobacterium,and Methanospirillum had higher relative abundance at the genus level.Therefore,SMR and OLR are important factor affecting the AD process,and OLR can affect methane production through volatile fatty acids.

Influence of climate fluctuations on Pinus palustris growth and drought resilience

The longleaf pine(Pinus palustris Mill.)ecosystem is an endangered ecosystem in the southeastern USA,and efforts to restore the species are ongoing.However,in recent decades,the region has experienced drastic fluctuations between wet and dry growing season conditions from year to year,and it is not fully understood how these fluctuations have influenced the growth of P.palustris.To address this topic,we cored P.palustris trees in woodlands of southwest Georgia and used dendrochronology techniques to determine how climate fluctuations have influenced the growth and drought resilience of P.palustris.We also cored slash pine(Pinus elliottii Engelm.)trees in the same woodlands to compare growth between species.While P.palustris growth was less impacted by adverse climate conditions compared to P.elliottii,the strength of correlations between P.palustris growth and temperature,precipitation,and Palmer Drought Severity Index(PDSI)changed over time.In recent decades,climate conditions during the growing season became more influential on P.palustris growth than the previous year's conditions.This is concerning given that drought severity during the growing season has been increasing.Our results also indicate that P.palustris was less resilient to droughts during the 2000s and 2010s than to those of the 1950s.Under this new climate paradigm,our results suggest that P.palustris might be more susceptible to growth reductions and less resistant to droughts than once expected.This work highlights the importance of understanding the impact of novel climate conditions on P.palustris and has implications for restoration efforts,such as using silvicultural treatments that reduce tree vulnerability to drought(e.g.,thinning)and promote other climate-adapted species in mixture with P.palustris.

Elemental geochemistry and Nd isotopic characteristics of the metasedimentary rocks from the metamorphic belt in central Jiangxi: Provenance and tectonically environmental constraints

The metamorphic belt in central Jiangxi, located in the compound terrain within the Cathaysia, Yangtze Block and Caledonian fold zone of South China, is composed dominantly of meta-argillo-arenaceous rocks, with minor amphibolite. These rocks underwent amphibolite-facies metamorphism. The meta-argillo-arenaceous rocks show large variations in major element composition, but have similar REE patterns and trace element composition, incompatible element and LIE enrichments [high Th/Sc ({0.57}-{3.59}), La/Sc ({1.46}-{12.4}), La/Yb ({5.84}-{19.0})] and variable Th/U ratios, with ΣREE=129-296μg/g, δEu={0.51}-{0.86}, and (La/Yb)-N={3.95}-{12.9}. The Nd isotopic model ages t-{DM} of these rocks vary from 1597 to 2124 Ma. Their {}+{143}Nd/+{144}Nd values are low [ε-{Nd}(0)={-11.4} to {-15.8}]. Some conclusions have been drawn as follows: (1) The metamorphic rocks in central Jiangxi Province are likely formed in a tectonic environment at the passive continental margin of the Cathaysia massif. (2) The metamorphosed argillo-arenaceous rocks are composed dominantly of upper crustal-source rocks (Al- and K|rich granitic or/and sedimentary rocks of Early Proterozoic), which experienced good sorting, slow deposition and more intense chemical weathering. (3) According to the whole-rock Sm-Nd isochron ages (1113±49 to 1199±26 Ma) of plagioclase-amphibole (schist) and Nd isotopic model age t-{DM} (1597-2124 Ma) of meta-argillo-arenaceous rocks, the metamorphic belt in central Jiangxi Province was formed during the Middle Proterozoic (1100-1600 Ma).

Diverse transformations of sulfur in seabird-affected sediments revealed by microbial and stable isotope analyses

Microbial communities,sulfur isotope of sulfides(δ^(34)S_(AVS)and δ^(34)S_(CRS)),and sulfur and oxygen isotopes of sulfate(δ^(34)S_(SO_(4))and δ^(18)O_(SO_(4)))in sediments were analyzed to reveal the biogeochemical transformations of sulfur in a seabird-affected lake Y2 and a se abird-free YO from Fildes Peninsula,Antarctic Peninsula.The microbial communities in Y2 were mainly associated with penguin activities,while those in YO were limited by nutrients.The much enriched δ^(34)S_(SO_(4))recorded at depth of 30,41,and 52 cm in Y2indicates very strong sulfate reduction therein.The sulfur-degrading bacteria Pseudomonas in 0-23 cm of Y2 was 3.5 time s as abundant as that of sulfur oxidizing bacteria(SOB),indicating remarkable remineralization of organic sulfur.The abundant SOB and ^(34)S-depleted sulfate indicate considerable sulfur oxidation in 34-56-cm layer in Y2.In YO sediments,the highest abundance of Desulfotalea and the most enriched δ^(34)S_(SO_(4))(35.2‰)and δ^(34)S_(CRS)(2.5‰)indicate the strongest sulfate reduction in 28-cm layer.High abundance of Pseudomonas indicates active remineralization of organic sulfur in 3-5-cm layer in YO.The medium δ^(34)S_(SO_(4))and considerable abundance of SOB and sulfate-reducing bacteria(SRB)indicate concurrence of sulfur oxidation and sulfate reduction in other layers in YO.Therefore,a high level of organic matter input from penguin populations supported the diverse microbial community and transformations of sulfur in aquatic ecosystems in Antarctica.

Spatial and Temporal Variations in the Atmospheric Age Distribution of Primary and Secondary Inorganic Aerosols in China

The aging timescale of particles is a key parameter in determining their impacts on air quality,human health,and climate.In this study,a one-year simulation of the age distributions of the primary and secondary inorganic fine particulate matter(PM_(2.5))components was conducted over China using an age-resolved Community Multiscale Air Quality(CMAQ)model.The results indicate that primary PM_(2.5)(PPM)and ammonium mainly originate from fresh local emissions,with approximately 60%-80%concentrated in 0-24 h age bins in most of China throughout the year.The average age is about15-25 h in most regions in summer,but increases to 40-50 h in southern region of China and the Sichuan Basin(SCB)in winter.Sulfate is more aged than PPM,indicating an enhanced contribution from regional transport.Aged sulfate with atmospheric age>48 h account for 30%-50%of total sulfate in most regions and seasons,and the concentrations in the>96 h age bin can reach up to 15μg·m-3 in SCB during winter.Dramatic seasonal variations occur in the Yangtze River Delta,Pearl River Delta,and SCB,with highest average age of 60-70 h in winter and lowest of 40-45 h in summer.The average age of nitrate is 20-30 h in summer and increases to 40-50 h in winter.The enhanced deposition rate of nitric acid vapor combined with the faster chemical reaction rate of nitrogen oxides leads to a lower atmospheric age in summer.Additionally,on pollution days,the contributions of old age bins(>24 h)increase notably for both PPM and secondary inorganic aerosols in most cities and seasons,suggesting that regional transport plays a vital role during haze events.The age information of PM_(2.5),provided by the age-resolved CMAQ model,can help policymakers design effective emergent emission control measures to eliminate severe haze episodes.

Characteristics of PM_(2.5) and Its Reactive Oxygen Species in Heating Energy Transition and Estimation of Its Impact on the Environment and Health in China——A Case Study in the Fenwei Plain

To reduce the adverse effects of traditional domestic solid fuel,the central government began implementing a clean heating policy in northern China in 2017.Clean coal is an alternative low-cost fuel for rural households at the present stage.In this study,18 households that used lump coal,biomass,and clean coal as the main fuel were selected to evaluate the benefits of clean heating transformation in Tongchuan,an energy city in the Fenwei Plain,China.Both indoor and personal exposure(PE)samples of fine particulate matter(PM_(2.5))were synchronically collected.Compared with the lump coal and biomass groups,the indoor PM_(2.5)concentration in the clean coal group is 43.6%and 20.0%lower,respectively,while the values are 16.8%and 21.3%lower,respectively,in the personal exposure samples.PM_(2.5)-bound elements Cd,Ni,Zn,and Mn strongly correlated with reactive oxygen species(ROS)levels in all fuel groups,indicating that transition metals are the principal components to generate oxidative stress.Using a reliable estimation method,it is predicted that after the substitution of clean coal as a household fuel,the all-cause,cardiovascular,and respiratory disease that causes female deaths per year could be reduced by 16,6,and 3,respectively,in the lump coal group,and 22,8,and 3,respectively,in the biomass group.Even though the promotion of clean coal has led to impressive environmental and health benefits,the efficiencies are still limited.More environmental-friendly energy sources must be promoted in the rural regions of China.

Comparison of three flocculants for heavy cyanobacterial bloom mitigation and subsequent environmental impact

Cyanobacteria can accumulate as a heavy biomass on the leeward side of large eutrophic lakes,posing a potential threat to public health.The mitigating capacity of three flocculants and their potential impacts on the major environmental features of water and sediments was evaluated.Results indicate that polyaluminum chloride(PAC)and ferric chloride(FeCl)are efficient flocculants that can rapidly mitigate cyanobacterial blooms with chlorophyll-a concentrations higher tnan 1500 ug/L within 15 min.In comparison,cationic starch with chitosan could only treat cyanobacterial blooms in chlorophyll-a concentrations of less than 200μg/L.The addition of FeClcaused a decline in the pH value,while dissolved oxygen in the water column dropped to 2 mg/L during cationic starch with chitosan treatment for a high cyanobacterial biomass group.Thus,a combination of flocculants and oxygenators should be considered when treating high-concentration cyanobacterial blooms for emergency purposes.Additionally,the cell lysis of cyanobacteria caused by cationic starch with chitosan can result in an increase in total dissolved phosphorus and total dissolved nitrogen.Furthermore,the high accumlation of nutrients in sediments after the settling of cyanobacteria can cause high internal phosphorus pollution.The increase in the total organic carbon of the sediments can threaten lake restoration achieved by planting submerged macrophytes.

Profiles and Source Apportionment of Nonmethane Volatile Organic Compounds in Winter and Summer in Xi’an, China, based on the Hybrid Environmental Receptor Model

Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).

Volatile Solid and Bury Period Influence on Odorous Material Production in Simulating Landfill Treatment

Odor pollution in landfill area has attracted more social attention in China. It is very important to control the generation of odor pollutants in situ. Analyzing odorous materials production form buried waste, simulated columns of different volatile solid (VS) content and different buried period waste were designed. Gas compounds produced from the columns were collected and analyzed by comprehensive two-dimensional gas chromatography (GC × GC) method. It has remarkable relationship between VS content and concentrations of odorous material. When VS content more than 40%, the total amount of odorous compounds increases remarkably. It can be inferred that reduced VS content of original waste may effective decreasing odorous materials production in landfill area. The old rubbish produced more odorous compounds than that of fresh one in simulated columns.

Effects of field application of phosphate fertilizers on the availability and uptake of lead, zinc and cadmium by cabbage (Brassica chinensis L.) in a mining tailing contaminated soil

A field trial was conducted to evaluate the reduction of bioavailability of heavy metals including lead (Pb), zinc (Zn) and cadmium (Cd) in a soil contaminated by mining tailings in Shaoxing, Zhejiang, China. Three commercial phosphate (P) fertilizers including phosphate rock (PR), calcium magnesium phosphate (CMP), and single superphosphate (SSP) were applied to the plot at three P application rates, 50, 300, and 500 g/m2 with 9 treatments and control (CK). Plants, water soluble and exchangeable (WE) extra...

Combined alkaline and ultrasonic pretreatment of sludge before aerobic digestion

Alkaline and ultrasonic sludge disintegration can be used as the pretreatment of waste activated sludge （WAS） to promote the subsequent anaerobic or aerobic digestion. In this study, different combinations of these two methods were investigated. The evaluation was based on the quantity of soluble chemical oxygen demand （SCOD） in the pretreated sludge as well as the degradation of organic matter in the subsequent aerobic digestion. For WAS samples with combined pretreatment, the released COD levels were higher than those with ultrasonic or alkaline pretreatment alone. When combined with the ultrasonic treatment, NaOH treatment was more efficient than Ca（OH）2 for WAS solubilization. The COD levels released in various sequential options of combined NaOH and ultrasonic treatments were in the the following descending order： simultaneous treatment 〉 NaOH treatment followed by ultrasonic treatment 〉 ultrasonic treatment followed by NaOH treatment. For simultaneous treatment, low NaOH dosage （100 g/kg dry solid）, short duration （30 min） of NaOH treatment, and low ultrasonic specific energy （7500 kJ/kg dry solid） were suitable for sludge disintegration. Using combined NaOH and ultrasonic pretreatment with optimal parameters, the degradation efficiency of organic matter was increased from 38.0% to 50.7%, which is much higher than that with ultrasonic （42.5%） or with NaOH pretreatment （43.5%） in the subsequent aerobic digestion at the same retention time.

Isolation and algae-lysing characteristics of the algicidal bacterium B5

Water blooms have become a worldwide environmental problem. Recently, algicidal bacteria have attracted wide attention as possible agents for inhibiting algal water blooms. In this study, one strain of algicidal bacterium B5 was isolated from activated sludge. On the basis of analysis of its physiological characteristics and 16S rDNA gene sequence, it was identified as Bacillusfusiformis. Its algaelysing characteristics on Microcystis aeruginosa, Chlorella and Scenedesmus were tested. The results showed that： （1） the algicidal bacterium B5 is a Gram-negative bacterium. The 16S rDNA nucleotide sequence homology of strain B5 with 2 strains of B. fusiformis reached 99.86%, so B5 was identified as B. fusiformis; （2） the algal-lysing effects of the algicidal bacterium B5 on M. aeruginosa, Chlorella and Scenedesrnus were pronounced. The initial bacterial and algal cell densities strongly influence the removal rates of chlorophyll-a. The greater the initial bacterial cell density, the faster the degradation of chlorophyll-a. The greater the initial algal cell density, the slower the degradation of chlorophyll-a. When the bacterial cell density was 3.6 × 10^7 cells/ml, nearly 90% of chlorophyll-a was removed. When the chlorophyll-a concentration was less than 550 μg/L, about 70% was removed; （3） the strain B5 lysed algae by secreting metabolites and these metabolites could bear heat treatment.

Evaluation of laboratory and environmental exposure systems for protein modification upon gas pollutants and environmental factors

Chemical modifications of proteins induced by ambient ozone(O_(3))and nitrogen oxides(NOx)are of public health concerns due to their potential to trigger respiratory diseases.The laboratory and environmental exposure systems have been widely used to investigate their relevant mechanism in the atmosphere.Using bovine serum albumin(BSA)as a model protein,we evaluated the two systems and aimed to reduce the uncertainties of both the reactants and products in the corresponding kinetic study.In the laboratory simulation system,the generated gaseous pollutants showed negligible losses.Ten layers of BSA were coated on the flow tube with protein extraction recovery of 87.4%.For environmental exposure experiment,quartz fiber filter was selected as the upper filter with low gaseous O_(3)(8.0%)and NO_(2)(1.7%)losses,and cellulose acetate filter was appropriate for the lower filter with protein extraction efficiency of 95.2%.The protein degradation process was observed without the exposure to atmospheric oxidants and contributed to the loss of protein monomer mass fractions,while environmental factors(e.g.,molecular oxygen and ultraviolet)may cause greater protein monomer losses.Based on the evaluation,the study exemplarily applied the two systems to protein modification and both showed that O_(3) promotes the protein oligomerization and nitration,while increased temperature can accelerate the oligomerization and increased relative humidity can inhibit the nitration in the environmental exposure samples.The developed laboratory and environmental systems are suitable for studying protein modifications formed under different atmospheric conditions.A combination of the two will further reveal the actual mechanism of protein modifications.

Status quo of soil petroleum contamination and evolution of bioremediation

Along with the rapid development of oil industries internationally,petroleum prospecting and exploitation activities are growing intensively.Especially in China,with the fastest economic growth in the world and shortage of petroleum resources,we are leading the practices of petroleum deep exploitation.Obviously,the risk of damage to the natural environment from these activities is high.Oil contamination in soils and groundwater is becoming a big issue along with pesticide pollution,which makes organic pollution prevention and control （OPPC） much more complex.In this paper,based on recent research on oil-contaminated soil at home and abroad,we make comments on the remediation technologies for polluted soil,emphasizing bioremediation techniques and degradation mechanisms in order to push forward research into bound organic pollution prevention and control （OPPC）,especially in China.

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

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.

Distribution and elimination of polycyclic musks in three sewage treatment plants of Beijing, China

The two representative polycyclic musks, 1-（5,6,7,8-tetrahydro-3,5,5,6,8,8-hexamethyl-2-naphthenyl）-ethanone （AHTN） and 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyrane （HHCB）, were measured in aqueous samples and sludge samples of three sewage treatment plants （STPs） in Beijing, China using a gas chromatograph-mass spectrometry. The HHCB and AHTN concentration ranges in the influents were 1251.4-3003.8 ng/L and 111.9-286.3 ng/L, respectively. Meanwhile, the ranges of 492.8-1285.3 ng/L for HHCB and 47.3-89.3 ng/L for AHTN were present in the effluents. The musks in the sludges were three to four orders of magnitude higher than those in aqueous sewages. The removal efficiencies.of the two musks varied in the ranges of 41.7%- 70.1% for HHCB, and 25.5%-68.8% for AHTN. Adsorption onto suspended particulate matter played an important role in removing musks from the sewages. The HHCB/AHTN ratio along the treatment processes showed that the two musks had high similarity of removal from sewage by each reactor in STP. The musks in the effluent sewages may pose a low potential risk to aquatic environment in terms of the predicted-non-effect concentration. Nevertheless, considering the possible additive and synergistic effects with other compounds emitted via STPs, their bioconcentration and bioaccumulation in aquatic organisms and so on, it is essential to monitor these compounds in various compartments and to study their environmental fate.

A novel biosorbent: characterization of the spent mushroom compost and its application for removal of heavy metals

The spent mushroom compost of Lentinus edodes was used as a biosorbent for adsorbing cadmium, lead and chromium from solutions under batch conditions for the first time. Titration of the biomass revealed that it contained at least three types of functional groups. The Fourier transform infrared spectrometry showed that the carboxyl, phosphoryl, phenolic groups were the main groups. The simulated values of pK, and molar quantity were 5.00 and 0.44 mmol/g, 7.32 and 1.38 mmol/g, 10.45 and 1.44 mmol/g, respectively. The biosorption ability increased with pH in acid condition. When 10 mg/L biomass dosage was added in, there was no significant increment of metal uptake. The maximum uptake estimated with the Langmiur isotherm model were 833.33 mg/g for Cd（ Ⅱ ）, 1000.00 mg/g for Pb（ Ⅱ ） and 44.44 mg/g for Cr（ Ⅲ ）, respectively. All the results showed that vast potential sorption capacity was existed in the biomass for adsorbing these three kinds of metals studied.

Applications of RS, GIS and GPS technologies in research, inventory and management of wetlands in China

这篇论文在遥感( RS )的应用程序，地理信息系统( GIS )和在沼泽地的全球 PositioningSystem ( GPS )研究的中国和圆盘虎耳草科酷栗属的植物介绍水陆地的国家，包括 land-coverclassification 和变化察觉，沼泽地进化过程，风景变化分析，隧道移植，监视的洪水和沼泽地资源和空间量的分析/建模，生态系统服务评估，生态的进程和风险评价，病害防治，监视/建模的水质， pollutionmonitoring/modeling ，沼泽地水文学，沼泽地信息系统和 WebGIS 。为这些技术的最佳的使用的限制和需要被讨论，例如有限先进技术知识和技巧，低了解和能力，在 GIS 输出之间的不清楚的连接并且政策做，支持政策和标准的缺乏，沼泽地geo信息 networklimite 的缺乏，并且在沼泽地研究的这些技术的使用。为认识到沼泽地相关的 geo 信息的 RS， GIS 和 GPS 技术，可获得性，可接近性，可靠性，同质，和连续性的真应用，启用环境，政策和标准，并且资助被需要，这被建议。

Construction and Characterization of an Atmospheric Simulation Smog Chamber

Currently, air pollution in Beijing has become a complex problem with two types of source pollutants： coal smoke and photochemical smog. Furthermore the maximum hourly mean concentration of O3 increases continuously, especially in the summer. In order to simulate the photochemical reaction, develop an air quality simulation model and further improve the air quality of Beijing, a precisely temperature-controlled, indoor, smog chamber facility was designed and constructed at Tsinghua University. Characterization experiments have been carried out to acquire the basic parameters of the smog chamber, such as the wall loss rates of NO2, NO, O3, C3H6 and particulate matter （PM）, the intensity of ultraviolet （UV） light in the chamber, the reactivity of the purified air and the reproducibility of the experimental results. The results indicate that the facility performs up to specifications, and can meet the demands required for simulating the photochemical reaction. The effect of high primary contaminated PM on the formation of ozone and secondary organic aerosol （SOA） is under investigation.