37 results on '"Xianfa Su"'
Search Results
2. Serratia spp. Are Responsible for Nitrogen Fixation Fueled by As(III) Oxidation, a Novel Biogeochemical Process Identified in Mine Tailings
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Yongbin Li, Lifang Guo, Max M. Häggblom, Rui Yang, Mengyan Li, Xiaoxu Sun, Zheng Chen, Fangbai Li, Xianfa Su, Geng Yan, Enzong Xiao, Haihan Zhang, and Weimin Sun
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Environmental Chemistry ,General Chemistry - Published
- 2022
3. The impact of three related emission industries on regional atmospheric chlorinated paraffins pollution
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Qilu Li, Shanshan Jiang, Yajing Li, Jingjing Su, Jingfang Shangguan, Mengdi Zhan, Yan Wang, Xianfa Su, Jun Li, and Gan Zhang
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China ,Paraffin ,Health, Toxicology and Mutagenesis ,Hydrocarbons, Chlorinated ,General Medicine ,Polyvinyl Chloride ,Environmental Pollution ,Toxicology ,Pollution ,Environmental Monitoring - Abstract
Identifying the contributions of various chlorinated paraffins (CPs) sources in the environment plays an important practical role in the prevention and control of the CPs contamination. However, little is known about how main CP-related emission industries affect the regional atmospheric characteristics of CPs, including CP products industry, metal working industry, and polyvinyl chloride (PVC) industry. In this study, 60 passive air samples were collected from five typical cities in Henan Province, China, which had serious CP pollution and different structures of CP-related emission industry. Short chain CPs (SCCPs) and medium chain CPs (MCCPs) were detected in all samples in concentrations ranging of 2.6-7.7 × 10
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- 2023
4. A seriously air pollution area affected by anthropogenic in the central China: temporal–spatial distribution and potential sources
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Jinglan Feng, Hao Yu, Yi Li, Jianhui Sun, and Xianfa Su
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Pollution ,China ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Air pollution ,Central china ,010501 environmental sciences ,Spatial distribution ,medicine.disease_cause ,01 natural sciences ,Air quality monitoring ,Spatio-Temporal Analysis ,Geochemistry and Petrology ,Air Pollution ,medicine ,Environmental Chemistry ,Cities ,0105 earth and related environmental sciences ,General Environmental Science ,Water Science and Technology ,media_common ,Air Pollutants ,General Medicine ,Particulates ,HYSPLIT ,Environmental science ,Particulate Matter ,Physical geography ,Environmental Monitoring - Abstract
This study used the officially released data by the Chinese air quality monitoring network to analyze the pollution characteristics of six air pollutants (PM2.5, PM10, SO2, NO2, CO, and O3) for 29 cities in the Central Plains Economic Zone (CPEZ; China) in 2015. During 2015, serious particulate matter (PM) pollution often occurred, and the concentrations of PM2.5 and PM10 were 77 μg m−3 and 128 μg m−3, respectively. Air pollutants were at higher concentrations in the northern cities than those in the southern region of the CPEZ, and the correlation among the cities indicated that there was regional pollution in CPEZ. Generally, PM, SO2, NO2, and CO showed similar seasonal characteristics and the highest and lowest concentrations appeared in winter and summer, respectively. In addition, we used the HYSPLIT model and trajStat model to identify the potential source contribution function and concentration-weighted trajectory of Zhengzhou, the central city of CPEZ. More serious air pollution occurred when air masses were transported from the west of the CPEZ. Shaanxi Province, Hubei Province, Anhui Province and the northwest of the CPEZ were found to be the main exogenous sources of total PM with contributions of > 100 μg m−3 PM2.5 and > 180 μg m−3 PM10. Therefore, the concentrations of PM in 2015 at Zhengzhou were probably influenced by both long-distance transmission and local emissions.
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- 2020
5. Distribution characteristics and noncarcinogenic risk assessment of culturable airborne bacteria and fungi during winter in Xinxiang, China
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Han Jingru, Xianfa Su, Hongyan Sun, Jianhui Sun, Jie Yang, Zheng Shikan, Xu Yan, Dezhi Qiu, and Wei Yue
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China ,Veterinary medicine ,Ultraviolet Rays ,Health, Toxicology and Mutagenesis ,Indoor bioaerosol ,Air Microbiology ,010501 environmental sciences ,Risk Assessment ,01 natural sciences ,Air Pollution ,Humans ,Environmental Chemistry ,Ecotoxicology ,Particle Size ,Air quality index ,0105 earth and related environmental sciences ,Aerosols ,Bacteria ,biology ,Diurnal temperature variation ,Fungi ,Humidity ,General Medicine ,Particulates ,biology.organism_classification ,Pollution ,Environmental science ,Particulate Matter ,Seasons ,Environmental Monitoring ,Bioaerosol - Abstract
Bioaerosols are an important component of particulate matter in the atmosphere and are harmful to human health. In this study, the concentration, size distribution, and factors influencing culturable airborne bacteria and fungi in the atmosphere were investigated using a six-stage impactor device in the city of Xinxiang, China, during the winter season. The results revealed that the concentration of culturable airborne bacteria and fungi varied significantly during the sampling period: 4595 ± 3410 and 6358 ± 5032 CFU/m3, respectively. The particle sizes of the bioaerosols were mainly within stage V (1.1-2.1 μm), and fine particulate matter accounted for 45.9% ± 18.9% of airborne bacteria and 52.0% ± 18.5% of airborne fungi, respectively. With the deterioration of air quality, the concentration of airborne fungi gradually increased, and that of airborne bacteria increased when the air quality index was lower than 200 and decreased when it was higher than 200. With respect to the diurnal variation pattern of bioaerosol concentration, the highest and lowest concentrations were registered at night and noon, respectively, probably because of changes in ultraviolet radiation intensity. Bioaerosol concentration positively correlated with humidity, concentration of PM2.5, PM10, SO2, and NO2 and negatively correlated with O3 concentration. The risk of exposure of humans to the airborne bacteria was primarily associated with the respiratory inhalation pathway, and the risk of skin exposure was negligible. These results should improve our understanding of the threat of bioaerosols to public health.
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- 2019
6. π-π conjugation driving degradation of aromatic compounds with in-situ hydrogen peroxide generation over Zn2In2S5 grown on nitrogen-doped carbon spheres
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Cuiwei Du, Weiwei Feng, Shiyu Nie, Xianfa Su, Haijin Liu, Jinglan Feng, Jianhui Sun, Chun Hu, and Shuying Dong
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Process Chemistry and Technology ,Catalysis ,General Environmental Science - Published
- 2022
7. Spatiotemporal distribution and mass loading of organophosphate flame retardants (OPFRs) in the Yellow River of China (Henan segment)
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Wei Guo, Han Jing, Shuying Dong, Xianfa Su, Xu Yan, Jinglan Feng, Jian Tian, and Jianhui Sun
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China ,Health, Toxicology and Mutagenesis ,Moderate level ,Organophosphate ,Suspended particles ,Dust ,General Medicine ,Particulates ,Contamination ,Toxicology ,Phosphate ,Pollution ,Mass loading ,Organophosphates ,chemistry.chemical_compound ,Organophosphorus Compounds ,chemistry ,Rivers ,Environmental chemistry ,Phase (matter) ,Flame Retardants - Abstract
During three sampling periods in 2014, systematic investigations were conducted into contamination profiles of ten organophosphate flame retardants (OPFRs) in both suspended particulate phase and water phase in the Yellow River (Henan Area). This research shows that OPFRs exist at lower concentrations in the suspended phase than in the water phase. The median concentration of 10 OPFRs (∑10OPFRs) in the suspended particulate phase was 62.5 ng/g (fluctuating from ND to 6.17 × 103 ng/g, dw), while their median concentration in the water phase was 109 ng/L (fluctuating from 35.6 to 469 ng/L). Among the selected 10 OPFRs, triethylphosphate (TEP), tris(1-chloro-2-propyl) phosphate (TCPP), and tris(2-chloroethyl) phosphate (TCEP) were the predominant compounds in the water phase (occupying 91.6% of the ∑10OPFRs), while TCPP, TCEP, and tri-o-tolyl phosphate (o-TCP) were the most common in the suspended particulate phase, accounting for 90.1% of the ∑10OPFRs. Across the three sampling periods, there was no significant seasonable variation for OPFRs either in the water phase or in the suspended particulate phase, except for TCEP and TCPP in the water phase. Compared with research findings relating to concentrations of OPFRs around China and abroad, the OPFRs of the Yellow River (Henan Area) in the water phase were at a moderate level. Suspended particles (SS) had a very important impact on the transportation of OPFRs in the studied area, with about 83.9% of ∑10OPFRs inflow attributed to SS inflow and about 81.7% of ∑10OPFRs outflow attributed to SS outflow. The total annual inflow and outflow of OPFRs were 7.72 × 104 kg and 6.62 × 104 kg in the studied area, respectively.
- Published
- 2021
8. Spatial and Temporal Distribution of Greenhouse Gas Emissions From Municipal Wastewater Treatment Plants in China From 2005 to 2014
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Dezhi Qiu, Ke Cheng, Yunping Han, Xianfa Su, Xu Yan, Zheng Shikan, and Jianhui Sun
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Wastewater ,business.industry ,Greenhouse gas ,Earth and Planetary Sciences (miscellaneous) ,Environmental engineering ,Environmental science ,Distribution (economics) ,China ,business ,Spatial distribution ,General Environmental Science - Published
- 2019
9. Fabrication of 3D ultra-light graphene aerogel/Bi2WO6 composite with excellent photocatalytic performance: A promising photocatalysts for water purification
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Zhang Fangyuan, Yongfa Zhu, Dong Shuying, Xia Longji, Li Kuiying, Cui Lingfang, Jinglan Feng, Canyu Liu, Xianfa Su, and Jianhui Sun
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Materials science ,Graphene ,General Chemical Engineering ,Composite number ,Aerogel ,Portable water purification ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Adsorption ,chemistry ,Chemical engineering ,law ,Rhodamine B ,Photocatalysis ,0210 nano-technology ,Visible spectrum - Abstract
Herein, we fabricated an ultra-light graphene aerogel/Bi2WO6 (GA/BW) photocatalyst with macroscopic 3D architecture via in-situ synthesis, which had preferable activity for organic wastewater purification. We carefully characterized the physical and chemical properties of this macroscopic 3D architecture, finding that the flower-like Bi2WO6 (BW) uniformly loaded on the surface of GA, improving the visible light absorption performance, photon-generated carrier separation efficiency and organic contaminants adsorption ability, as well as photocatalytic ability compared with that of pure BW powders. When the mass ratio of GA and BW is 6:8, the degradation efficiency of rhodamine B (RhB) and sulfanilamide (SN) can reach 97.49% and 55.81% in 120 min, respectively. The as-prepared GA/BW composite is ultra-light and suitable for practical wastewater purification due to its flexibility and recyclability. The trapping experiments involved the main active species in the photocatalytic process were carried out and the results indicated that the h+ is the dominant oxidative species for the degradation of RhB.
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- 2019
10. Comparison of Black Carbon, Total Organic Carbon, and PAH Concentrations in Surface Sediments from Two Main Rivers in Henan Province, China
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Nannan Xi, Jianhui Sun, Jinglan Feng, and Xianfa Su
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Total organic carbon ,010504 meteorology & atmospheric sciences ,Environmental chemistry ,Environmental science ,Carbon black ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,China ,01 natural sciences ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Black carbon (BC) in surface sediments from Henan section of Yellow River and Huaihe River, China, was determined. Average content of BC in Huaihe River was 0.33%, higher than that in Yellow River ...
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- 2019
11. Crystal structure and photocatalytic properties of perovskite MSn(OH)6 (M = Cu and Zn) composites with d10-d10 configuration
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Zhang Chunyan, Xianfa Su, Shuying Dong, Wei Guo, Wu Yawen, Cui Lingfang, Jianhui Sun, Dong Wang, Xia Longji, and Yinlan Zhao
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Ionic radius ,Materials science ,Diffuse reflectance infrared fourier transform ,Coprecipitation ,General Physics and Astronomy ,02 engineering and technology ,Surfaces and Interfaces ,General Chemistry ,Crystal structure ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Surfaces, Coatings and Films ,law.invention ,Chemical bond ,law ,Photocatalysis ,Physical chemistry ,Calcination ,0210 nano-technology ,Perovskite (structure) - Abstract
In this study, hexahydroxy-stannates (MSn(OH)6 (M = Cu, Zn)) with d10-d10 configuration were synthesized by using a simple coprecipitation method at room temperature to investigate the effect of cationic substitution with similar ionic radius. The obtained samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis, Fourier transform-infrared spectra (FT-IR) and UV–Vis diffuse reflectance spectroscopy, etc. The photocatalytic properties of the obtained samples were evaluated by the degradation of methylene blue (MB). It is found that the difference of M2+ in MSn(OH)6 bring a change in crystal structure, morphology, chemical bond energy and photocatalytic property. The obtained MSn(OH)6 nanoparticles can be used to the preparation of the different mixtures by simple calcination, but the photocatalytic performance could not be improved after the heat treatment duo to the change of crystal structure by forming the mixture of oxide. These results suggested that metal cations in A sites could induce lattice distortion of the hexahydroxy-stannates with d10-d10 configuration although they have the similar ionic radius, accordingly inducing the change of morphology, chemical bond energy and photocatalytic activity.
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- 2019
12. Impact of suspended sediment on the behavior of polycyclic aromatic hydrocarbons in the Yellow River: Spatial distribution, transport and fate
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Jianhui Sun, Qilu Li, Jinglan Feng, Xianfa Su, Yi-Fan Li, and Pengtuan Hu
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010504 meteorology & atmospheric sciences ,Geochemistry and Petrology ,Environmental chemistry ,Environmental Chemistry ,Environmental science ,Sediment ,010501 environmental sciences ,Spatial distribution ,01 natural sciences ,Pollution ,0105 earth and related environmental sciences - Abstract
A total of 150 samples were collected from 25 sites in the Yellow River of Henan Province during 2014 to demonstrate the impact of suspended sediment (SS) load on the behavior of semi-volatile organic compounds (SVOCs) in the Yellow River. The average concentrations of SS ranged from
- Published
- 2018
13. Effect of carbon source on nitrous oxide emission characteristics and sludge properties during anoxic/aerobic wastewater treatment process
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Jiahui Ma, Xianfa Su, Xu Yan, Jie Yang, Jianhui Sun, and Guo Dongli
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Nitrogen ,Health, Toxicology and Mutagenesis ,Nitrous Oxide ,chemistry.chemical_element ,010501 environmental sciences ,01 natural sciences ,Waste Disposal, Fluid ,Water Purification ,chemistry.chemical_compound ,Denitrifying bacteria ,Acetic acid ,Extracellular polymeric substance ,Bioreactors ,Aerobic denitrification ,Environmental Chemistry ,0105 earth and related environmental sciences ,Sewage ,Extracellular Polymeric Substance Matrix ,General Medicine ,Nitrous oxide ,equipment and supplies ,Pollution ,Anoxic waters ,Nitrification ,Carbon ,chemistry ,Environmental chemistry ,Denitrification ,Sewage treatment - Abstract
Carbon sources are an important parameter in wastewater treatment processes and are closely related to treatment efficiency and nitrous oxide (N2O) emissions. In this study, three parallel sequencing batch reactors (SBRs) were processed with acetic acid, propionic acid, and a 1:1 mixture of both acids (calculated in COD) to study the effect of carbon sources on N2O generation and sludge properties (including intracellular polymer content, extracellular polymeric substance (EPS) composition, particle size distribution, settleability, and microbial community structure). The results showed that the highest COD, NH4+-N, and TP removal efficiencies (92.2%, 100%, and 82.3%, respectively) were achieved by the reactor with mixed acid as the carbon source, whereas the reactor using acetic acid had the highest TN removal rate (82.6%) and the lowest N2O-N conversion rate (1.4%, based on TN removal). The reactor with the carbon source of mixed acid produced the highest polyhydroxyalkanoate (PHA) content, which led to an increase in N2O generation from the aerobic denitrification pathway. The SBR with mixed acid carbon source also had the highest concentration of EPS, which resulted in the largest particle size and the lowest settleability of sludge flocs among the SBRs. Microbial analysis results revealed that the difference in carbon sources resulted in a variation in the microbial community as well as in the relative abundances of functional microbes involved in biological nitrogen removal processes. The mixed acid promoted the development of ammonia-oxidizing bacteria (AOB), which conducted the primary N2O generation pathway of aerobic denitrification bioreactions. The carbon source of acetic acid promoted the growth of denitrifying bacteria (DNB), which led to the highest TN removal rate. This study provides a comprehensive understanding of the effects of carbon sources on N2O generation and sludge properties for WWTPs.
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- 2020
14. Degradation of Diclofenac Sodium by Pre-magnetization Fe0/Persulfate System: Efficiency and Degradation Pathway Study
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Yan Jia, Minghua Zhou, Xianfa Su, Jianhui Sun, Xiang Li, and Linjie Ding
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Environmental Engineering ,Chemistry ,Ecological Modeling ,Diclofenac Sodium ,010501 environmental sciences ,Persulfate ,01 natural sciences ,Pollution ,Mineralization (biology) ,law.invention ,Magnetization ,Reaction rate constant ,law ,Environmental Chemistry ,Degradation (geology) ,Electron paramagnetic resonance ,Degradation pathway ,0105 earth and related environmental sciences ,Water Science and Technology ,Nuclear chemistry - Abstract
The degradation of diclofenac sodium (DCF) in pre-magnetization Fe0/persulfate (Pre-Fe0/PS) and Fe0/PS systems were studied in detail in this study. The influencing operational conditions (initial PS dosage, Fe0 dosage, and pH) were studied for their effects on the DCF degradation. The removal rate constant for DCF by the Pre-Fe0/PS system was 2.1–6.2 times higher than that of the Fe0/PS system. A higher TOC removal efficiency (81.5%) was observed during the mineralization of DCF in the Pre-Fe0/PS process than that of the Fe0/PS process (70%). The results of electron paramagnetic resonance (EPR) confirmed that the Pre-Fe0/PS system could produce much more •OH and SO4−• at a faster rate than the Fe0/PS system. Moreover, the degradation mechanism of DCF by the Pre-Fe0/PS process was elucidated. This work would provide a perspective on the Pre-Fe0/PS process for efficient degradation of DCF, exhibiting advantages to removing DCF, such as broaden the range of working pH and reduce the amount of chemicals. So, it is an efficient and potential method to remove DCF from wastewater by the Pre-Fe0/PS process.
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- 2020
15. Effects of hydrodynamic shear stress on sludge properties, N
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Xu, Yan, Shikan, Zheng, Jie, Yang, Jiahui, Ma, Yunping, Han, Jinglan, Feng, Xianfa, Su, and Jianhui, Sun
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Bioreactors ,Sewage ,Nitrogen ,Microbiota ,Denitrification ,Hydrodynamics ,Nitrous Oxide - Abstract
Sludge properties are critical to the treatment performance and potentially correlate with nitrous oxide (N
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- 2020
16. Utilization of all components in biomass through high reducing sugar production and lignin nanoparticles preparation
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Kejing Zhang, Shi Yan, Aizi Tong, Xianfa Su, Wei Liu, Shengnan Zhuo, and Mengying Si
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chemistry.chemical_classification ,chemistry.chemical_compound ,chemistry ,Biomass ,Production (economics) ,Lignin ,Nanoparticle ,Pulp and paper industry ,Reducing sugar - Abstract
BackgroundLignocellulosic biomass for biofuel production was considered as an effective way to develop new energy. However, the efficient sugar conversion of cellulose and practical utilization of lignin are great challenges for sustainable biorefinery. In addition, sugar conversion and lignin utilization are generally performed separately. In this study, high reducing sugar production and multiple lignin nanoparticles preparation were realized in a pattern based on tetrahydrofuran-water (THF-H2O) pretreatment of corn straw (CS). ResultsThe maximum production of the reducing sugar was 26.79 g/l, which was significantly higher than the theoretical yield of 20.65 g/l. Lignin nanoparticles with different sizes ranged from 239 to 798 nm were prepared using dissolved lignin in the supernatant fluid from different THF-H2O pretreatment conditions through self-assembly with introducing water. The formation of lignin particles with different sizes were influenced by soluble lignin characteristics in the pretreatment liquid. The lignin molecular, functional groups, and structure were explored to elucidate the effects on the variation of lignin particles sizes by GPC, FTIR, and 2D-HSQC-NMR. The guaiacyl (G)-type lignin was easier to be dissolved in the mild pretreatment liquid, contributing to form smaller lignin nanoparticles with a good dispersibility. Comparatively, a small content of syringyl- and G-type lignin which caused by the lignin depolymerization retained in the severe pretreatment liquid to form the larger sphere particles. ConclusionsThe optimal pretreatment under TH22 (THF-H2O pretreatment at 120 °C for 2 h) simultaneously realized the utilization of all components in biomass through high reducing sugar production and the smaller lignin particles preparation. This new pattern of CS pretreatment plays a novel perspective for the technical design of lignocellulosic biomass conversion.
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- 2019
17. Controlled synthesis of flexible graphene aerogels macroscopic monolith as versatile agents for wastewater treatment
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Zhang Fangyuan, Shuying Dong, Teng Guo, Dong Wang, Jianhui Sun, Xia Longji, Wei Guo, Cui Lingfang, and Xianfa Su
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Materials science ,Oxide ,General Physics and Astronomy ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Industrial wastewater treatment ,chemistry.chemical_compound ,law ,Monolith ,Porosity ,geography ,geography.geographical_feature_category ,Aqueous solution ,Graphene ,Aerogel ,Surfaces and Interfaces ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry ,Chemical engineering ,0210 nano-technology ,Carbon - Abstract
Emerging applications for environmental purification require agents that not only possess high decontamination efficiency, but also are capable of withstanding mechanical deformation without secondary pollution and degradation of performance. To this end, we have controlled synthesis of mechanically flexible graphene aerogel (GA) by vacuum freeze-drying of their hydrogel precursors obtained from heating the aqueous mixtures of graphene oxide (GO) and Vitamin C (VC) without stirring. Through the adaptable process conditions, such as the particle size of carbon, GO concentration, dosage of reducing agent and solution pH, the highly porous, ultralight and mechanically flexible GA are synthesized. Owing to the porous, robust and stable structure, the resulting GA show very promising performance in water purification including enrichment of organic liquid solvents (alcohols, oil and alkanes), removal of hexavalent chromium Cr(VI) and purified industrial wastewater, as well as flexible conductors. The successful creation of the GA may provide new insights into the design of carbon-based aerogels for various applications, as the GA can be prepared via a very simple procedure and available in macroscopic diverse morphologies with tunable porosity.
- Published
- 2018
18. One year study of PM2.5 in Xinxiang city, North China: Seasonal characteristics, climate impact and source
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Qilu Li, Jinglan Feng, Jianhui Sun, Xianfa Su, Hao Yu, Kai Mi, and Yi Li
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010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,North china ,General Medicine ,010501 environmental sciences ,01 natural sciences ,Pollution ,Ambient air ,Climate impact ,Environmental chemistry ,Environmental science ,Composition (visual arts) ,0105 earth and related environmental sciences - Abstract
This study was conducted in order to explore the seasonal characteristics, climate impact and source of PM2.5 in Xinxiang, China. Daily PM2.5 samples were collected at urban site from January to December in 2015. Average PM2.5 concentration was 100.6 ± 65.8 μg m−3 in Xinxiang, which was several times higher than China Ambient Air Quality Standards (GB3095-2012). Secondary inorganic aerosols (SIA) constituted 70% of the total ionic concentrations. The average concentration of SO42- was 6.4 ± 12.0 μg m−3, which ranked the highest among the water-soluble ions analyzed. Seasonal variations of PM2.5 and its major chemical components were significant, most of them with high values in winter and the lowest values in summer, especially with heavier PM2.5 events (more than 200 μg/m3) in December. SIA and OC on polluted days were 2.1–2.3 times higher than those of on clean days. It was estimated that Fe, Li, Na, Mg, Al, K, Ca and Sr were emitted from crustal sources and Pb, Cr, Ni, Cu, Zn, As, Cd and V were emitted from anthropogenic emissions using the EF values. Analysis using the tracer and PCA/MLR revealed that vehicle exhausts were the most important source of PM2.5, which contributed 26.9% of PM2.5 over the whole study period. This study provides detailed composition data and first comprehensive analysis of PM2.5 in Xinxiang during a whole year.
- Published
- 2018
19. Polychlorinated biphenyls in the Yellow River of Henan section: occurrence, composition, and impact factors
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Jinglan Feng, Qi Liu, Jianhui Sun, Xianfa Su, and Liya Guo
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China ,Geologic Sediments ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,010501 environmental sciences ,01 natural sciences ,Rivers ,Tributary ,Environmental Chemistry ,Ecotoxicology ,Water pollution ,Ecosystem ,0105 earth and related environmental sciences ,Total organic carbon ,No-Observed-Adverse-Effect Level ,geography ,geography.geographical_feature_category ,Atmosphere ,Sediment ,General Medicine ,Polychlorinated Biphenyls ,Pollution ,Congener ,Environmental chemistry ,Environmental science ,Spatial variability ,Water quality ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
The levels, spatial variation, congener profiles, impact factors, and ecological risk of polychlorinated biphenyls (PCBs) in the sediment from the Yellow River of Henan section, China, were investigated in this paper. Total concentration of 31 PCBs and seven indicator PCBs varied from ND to 1015 pg g-1 and ND to 423 pg g-1, respectively. Compared with other aquatic environments around China, PCB levels in the studied area were relatively low. Spatial variations revealed that tributaries possessed higher PCB levels, in comparison to mainstream, which acted as input sources of PCBs in the mainstream. The homolog profiles were dominated by lighter PCBs (Tri-PentaCBs), contributing above 70% of total PCBs. Correlation analysis between PCB concentrations and total organic carbon indicated that local input or atmospheric deposition was the primary controls of spatial variation of PCBs. According to simple sediment quality guidelines (SQG), the risks posed by PCBs in the sediments might be negligible.
- Published
- 2018
20. Legacy and emerging halogenated flame retardants in the middle and lower stream of the Yellow River
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Liya Guo, Xianfa Su, Jinglan Feng, Jianhui Sun, and Qilu Li
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Pollutant ,education.field_of_study ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Population ,Environmental engineering ,Sediment ,010501 environmental sciences ,Dechlorane plus ,01 natural sciences ,Pollution ,chemistry.chemical_compound ,chemistry ,Environmental chemistry ,Environmental Chemistry ,Environmental science ,education ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Halogenated flame retardants (HFRs), mainly encompassing polybrominated diphenylethers (PBDEs), dechlorane plus (DP) and emerging bromine flame retardants (EBFRs), are widely employed nowadays in daily lives. However, limited knowledge has been gained to date on the concentrations and distributions of HFRs in particular within certain regions. In the present study, legacy and emerging HFRs were systematically measured in suspended particle matter (SPM) and sediments collected in 2014 from the middle and lower reach of the Yellow River in Henan province. The total concentrations of HFRs in SPM among the three seasons were 42.2±91.2ngg-1, which was far higher than the corresponding values of HFRs in sediments (1.82±2.94ngg-1). In this study, PBDEs, DP and EBFRs in sediment almost exhibited relatively lower levels as compared to those found in other studies, where the limited usage of HFRs in the middle and lower stream of the Yellow River was probably the major impact factor. EBFR was the predominate pollutant from SPM and sediments in most of the sampling sites, suggesting that EBFRs were widely used nowadays as substitute materials of 'old' FRs. The mean concentration values of DBDPE/BDE-209 in SPM and sediments were apparently higher than those of previous studies. Furthermore, it is interesting to reveal that herein almost all of the HFR concentrations were unrelated to the population and GDP, which might be attributed to the characteristics of 'elevated stream' of the Yellow River as well as the complex river systems in Henan province.
- Published
- 2017
21. Studies on thermokinetic of Chlorella pyrenoidosa devolatilization via different models
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Dabin Guo, Zhihua Chen, Yunbei Li, Jianshen Lei, Zhiquan Hu, and Xianfa Su
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Environmental Engineering ,Order of reaction ,020209 energy ,Thermodynamics ,Bioengineering ,Chlorella ,02 engineering and technology ,Activation energy ,010501 environmental sciences ,Kinetic energy ,01 natural sciences ,Botany ,0202 electrical engineering, electronic engineering, information engineering ,Chlorella pyrenoidosa ,Waste Management and Disposal ,0105 earth and related environmental sciences ,Logistic distribution ,biology ,Renewable Energy, Sustainability and the Environment ,Chemistry ,General Medicine ,biology.organism_classification ,Kinetics ,Logistic Models ,Thermokinetics ,Distribution function ,Thermogravimetry ,Mass fraction - Abstract
The thermokinetics of Chlorella pyrenoidosa (CP) devolatilization were investigated based on iso-conversional model and different distributed activation energy models (DAEM). Iso-conversional process result showed that CP devolatilization roughly followed a single-step with mechanism function of f(α) = (1 − α)3, and kinetic parameters pair of E0 = 180.5 kJ/mol and A0 = 1.5E + 13 s−1. Logistic distribution was the most suitable activation energy distribution function for CP devolatilization. Although reaction order n = 3.3 was in accordance with iso-conversional process, Logistic DAEM could not detail the weight loss features since it presented as single-step reaction. The un-uniform feature of activation energy distribution in Miura-Maki DAEM, and weight fraction distribution in discrete DAEM reflected weight loss features. Due to the un-uniform distribution of activation and weight fraction, Miura-Maki DAEM and discreted DAEM could describe weight loss features.
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- 2017
22. Effect of feed water characteristics on nanofiltration separating performance for brackish water treatment in the Huanghuai region of China
- Author
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Tiemei Li, Yuefei Song, Congjie Gao, and Xianfa Su
- Subjects
Brackish water ,Fouling ,Chemistry ,Process Chemistry and Technology ,Environmental engineering ,Ultrafiltration ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Pulp and paper industry ,Total dissolved solids ,Membrane ,020401 chemical engineering ,Dissolved organic carbon ,Water quality ,Nanofiltration ,0204 chemical engineering ,0210 nano-technology ,Safety, Risk, Reliability and Quality ,Waste Management and Disposal ,Biotechnology - Abstract
In this paper, one brackish groundwater quality, which represented typically the water quality in the Huanghuai region of China, was simulated and used to run a bench-scale ultrafiltration (UF)–nanofiltration (NF) system. The influences of feed pH (3.0–10.0), feed total dissolved solids (TDS) (1182–5319 mg L−1) and feed dissolved organic carbon (DOC) (0.54–2.43 mg L−1) on the separating efficiencies of two different NF membranes (Thin-Film Composite (DL) and Polyamide (DK)) were investigated. In addition, long-term operation for 580 h was also conducted by the superior NF membrane to evaluate the performance stability and fouling potential after a number of subsequent cleaning cycles. Within the scope of the test, NF separating performance in terms of salt rejection showed different changing tendencies: V-shaped curve for pH, inverted V-shaped curve for TDS and linear curve for DOC. While in general, specific permeate flux was reduced in different degrees except for DK membrane with feed pH variation. The observed separating performance decline with operating time was mainly due to the scale formation on the NF membrane surface, which was rinsed effectively (FR1 = 97.80% and RR1 = 61.63%; FR2 = 95.40% and RR2 = 49.35%) by chemical cleaning, as certified by FESEM−EDX and AFM images.
- Published
- 2017
23. Pollution characteristics, temporal records, and risks associated with parabens and mercury in sediments from the upper Huai River, Henan Province
- Author
-
Jinglan Feng, Wei Guo, Jiahui Zhao, Xiangli Ru, Jianhui Sun, Shuying Dong, and Xianfa Su
- Subjects
Total organic carbon ,Pollution ,geography ,geography.geographical_feature_category ,Methylparaben ,media_common.quotation_subject ,chemistry.chemical_element ,010501 environmental sciences ,010502 geochemistry & geophysics ,01 natural sciences ,Mercury (element) ,chemistry.chemical_compound ,chemistry ,Geochemistry and Petrology ,Environmental chemistry ,Tributary ,Environmental science ,Economic Geology ,Precipitation ,0105 earth and related environmental sciences ,media_common - Abstract
Mercury (Hg), six alkyl esters of p-hydroxybenzoic acid (parabens), and their metabolite, 4-hydroxybenzoic acid (PHBA), were simultaneously studied in sediments from the upper Huai River, Henan Province, China. There were higher concentrations of Hg in the surface sediments from the Huai River during the moderate precipitation season (MPS②) as compared to the minimal precipitation (MPS①) and high precipitation seasons (HPS), and as compared to core sediments. The Hg values in all sediments were above the background value. The Hg contents in the tributaries were much higher than those in the mainstream. The concentrations of ∑parabens in the core sediments ranged from 2.45 to 22.2 ng/g while the concentrations of PHBA ranged from 11.3 to 155 ng/g. Methylparaben (MeP) and propylparaben (PrP) were the most commonly detected parabens. Total organic carbon (TOC) and black carbon (BC) played important roles in the distribution of Hg in the surface sediments during the minimal precipitation and high precipitation seasons and affect the distribution of Hg and parabens in core sediments. Sand (>63 μm) was another factor affecting the distribution of Hg and parabens in core sediments. The concentrations of PHBA and Hg in core sediments were positively correlated. Temporal records of Hg and parabens in core sediments reflected local social changes. Hg content in the surface sediments during the MPS② was associated with relatively high ecological risks while parabens in the core sediments were associated with low level risks.
- Published
- 2021
24. Impacts of human activities on the spatial distribution and sources of polychlorinated naphthalenes in the middle and lower reaches of the Yellow River
- Author
-
Xianghui Cheng, Xianfa Su, Gan Zhang, Jun Li, Yan Wang, Jianhui Sun, Liya Guo, Kechang Li, Qilu Li, and Zhineng Cheng
- Subjects
China ,Geologic Sediments ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,Health, Toxicology and Mutagenesis ,Coal combustion products ,Naphthalenes ,010501 environmental sciences ,Combustion ,Spatial distribution ,01 natural sciences ,Rivers ,Hydrocarbons, Chlorinated ,Humans ,Environmental Chemistry ,Human Activities ,Coal ,Energy structure ,0105 earth and related environmental sciences ,business.industry ,Public Health, Environmental and Occupational Health ,Sediment ,General Medicine ,General Chemistry ,Particulates ,Pollution ,Congener ,Environmental chemistry ,Environmental science ,business ,Water Pollutants, Chemical ,Environmental Monitoring - Abstract
The concentrations and compositions of polychlorinated naphthalenes (PCNs) in sediments and suspended particulate matters (SPM) in the middle and lower reaches of the Yellow River were investigated. The mean concentrations of PCNs were 7.15 ± 19.3 ng/g dw in the sediment and 38.1 ± 58.4 ng/g dw in SPM. Tri- and tetra-CNs were the dominant homologue groups in most samples. CN-23 was the predominant congener at all sites, and its presence may be attributed to coal combustion. Combustion indicators showed that local combustion source was the main contributor to the PCN concentrations. These sources were related to the energy structure of this region, where coal is the most important energy resource. Human activities, including industrial thermal processes and reservoir construction, were major factors affecting PCN levels and hydrological conditions, which strongly influenced the environmental fate of PCNs in the Yellow River.
- Published
- 2017
25. The pollution characteristics of PM2.5 and correlation analysis with meteorological parameters in Xinxiang during the Shanghai Cooperation Organization Prime Ministers’ Meeting
- Author
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Jianhui Sun, Jinglan Feng, Yunqi Chen, Qilu Li, Hao Yu, Kai Mi, and Xianfa Su
- Subjects
Total organic carbon ,Pollution ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Environmental engineering ,Fossil fuel combustion ,General Medicine ,Limiting ,010501 environmental sciences ,01 natural sciences ,Aerosol ,Geochemistry and Petrology ,Correlation analysis ,Environmental Chemistry ,Environmental science ,Relative humidity ,Elemental carbon ,0105 earth and related environmental sciences ,General Environmental Science ,Water Science and Technology ,media_common - Abstract
The pollution characteristics of PM2.5 and correlation analysis with meteorological parameters in Xinxiang during the Shanghai Cooperation Organization Prime Ministers’ Meeting were investigated. During the whole meeting, nine PM2.5 samples were collected at a suburban site of Xinxiang, and the average concentration of PM2.5 was 122.28 μg m−3. NO3 −, NH4 +, SO4 2− accounted for 56.8% of the total water-soluble ions. In addition, with an exception of Cl−, all of water-soluble ions decreased during the meeting. Total concentrations of crustal elements ranged from 6.53 to 185.86 μg m−3, with an average concentration of 52.51 μg m−3, which accounted for 82.5% of total elements. The concentrations of organic carbon and elemental carbon were 7.71 and 1.52 μg m−3, respectively, lower than those before and after the meeting. It is indicated that during the meeting, limiting motor vehicles is to reduce exhaust emissions, delay heating is to reduce the fossil fuel combustion, and other measures are to reduce the concentration of PM2.5. The directly dispersing by mixing layer height increase and the indirectly reducing the formation of secondary aerosol by low relative humidity, and these are the only two key removing mechanisms of PM2.5 in Xinxiang during the meeting.
- Published
- 2017
26. Chemical composition and source apportionment of PM2.5 during Chinese Spring Festival at Xinxiang, a heavily polluted city in North China: Fireworks and health risks
- Author
-
Yi Li, Hao Yu, Jian-hui Sun, Shuhui Liu, Xianfa Su, Jinglan Feng, and Yuepeng Pan
- Subjects
Atmospheric Science ,Haze ,010504 meteorology & atmospheric sciences ,Meteorology ,Chinese spring ,Air pollution ,North china ,Fireworks ,Heavy metals ,010501 environmental sciences ,medicine.disease_cause ,01 natural sciences ,Environmental chemistry ,medicine ,Environmental science ,Chemical composition ,Air quality index ,0105 earth and related environmental sciences - Abstract
Twenty-four PM 2.5 samples were collected at a suburban site of Xinxiang during Chinese Spring Festival (SF) in 2015. 10 water-soluble ions, 19 trace elements and 8 fractions of carbonaceous species in PM 2.5 were analyzed. Potential sources of PM 2.5 were quantitatively apportioned using principal component analysis (PCA)-multivariate linear regressions (MLR). The threat of heavy metals in PM 2.5 was assessed using incremental lifetime cancer risk (ILCR). During the whole period, serious regional haze pollution persisted, the average concentration of PM 2.5 was 111 ± 54 μg m − 3 , with 95.8% and 79.2% of the daily samples exhibiting higher PM 2.5 concentrations than the national air quality standard I and II. Chemical species declined due to holiday effect with the exception of K, Fe, Mg, Al and K + , Cl − , which increased on Chinese New Year (CNY)'s Eve and Lantern Festival in 2015, indicating the injection of firework burning particles in certain short period. PM 2.5 mass closure showed that secondary inorganic species were the dominant fractions of PM 2.5 over the entire sampling (37.3%). 72-hour backward trajectory clusters indicated that most serious air pollution occurred when air masses transported from the Inner Mongolia, Shanxi and Zhengzhou. Health risk assessment revealed that noncancerous effects of heavy metals in PM 2.5 of Xinxiang were unlikely happened, while lifetime cancer risks of heavy metals obviously exceeded the threshold, which might have a cancer risk for residents in Xinxiang. This study provided detailed composition data and first comprehensive analysis of PM 2.5 during the Spring Festival period in Xinxiang.
- Published
- 2016
27. Characteristics of N
- Author
-
Xu, Yan, Shikan, Zheng, Dezhi, Qiu, Jie, Yang, Yunping, Han, Zhaoman, Huo, Xianfa, Su, and Jianhui, Sun
- Subjects
Oxygen ,Sewage ,Nitrogen ,Nitrous Oxide ,Particle Size - Abstract
Nitrous oxide (N
- Published
- 2019
28. Effects of hydrodynamic shear stress on sludge properties, N2O generation, and microbial community structure during activated sludge process
- Author
-
Jianhui Sun, Xu Yan, Yunping Han, Jiahui Ma, Jinglan Feng, Jie Yang, Xianfa Su, and Zheng Shikan
- Subjects
Environmental Engineering ,0208 environmental biotechnology ,02 engineering and technology ,General Medicine ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,020801 environmental engineering ,chemistry.chemical_compound ,Denitrifying bacteria ,Activated sludge ,Extracellular polymeric substance ,Microbial population biology ,chemistry ,Environmental chemistry ,Shear stress ,Sewage treatment ,Aeration ,Nitrite ,Waste Management and Disposal ,0105 earth and related environmental sciences - Abstract
Sludge properties are critical to the treatment performance and potentially correlate with nitrous oxide (N2O) generation during activated sludge processes. The hydrodynamic shear stress induced by aeration has a significant influence on sludge properties and is inevitable for wastewater treatment plants (WWTPs). In this study, the effects of aerobic induced hydrodynamic shear stress on sludge properties, N2O generation, and microbial community structure were investigated using three parallel sequencing batch reactors (SBRs) with identical dissolved oxygen (DO) concentrations. Results showed that with a shear stress increase from 1.5 × 10−2 N/m2 to 5.0 × 10−2 N/m2, the COD and NH4+-N removal rates were enhanced from 89.4% to 94.0% and from 93.9% to 98.0%, respectively, while the TN removal rate decreased from 66.0% to 56.5%. Settleability of the activated sludge flocs (ASFs) also increased with the enhancement of shear stress, due to variation in sludge properties including particle size, regularity, compactibility, and EPS (extracellular polymeric substances) composition. The increase in shear stress promoted oxygen diffusion within the ASFs and mitigated NO2−-N accumulation, leading to a decrease in the N2O–N conversion rate from (4.8 ± 0.3)% to (2.2 ± 0.6)% (based on TN removal). Microbial analysis results showed that the functional bacteria involved in the biological nitrogen removal was closely related with shear stress. The increase in shear stress favored the enrichment of nitrite oxidizing bacteria (NOB) while suppressed the accumulation of ammonia-oxidizing bacteria (AOB) and denitrifying bacteria (DNB).
- Published
- 2020
29. High-efficiency degradation of organic pollutants with Fe, N co-doped biochar catalysts via persulfate activation
- Author
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Yan Jia, Minghua Zhou, Xiang Li, Jianhui Sun, and Xianfa Su
- Subjects
Environmental Engineering ,Iron ,Health, Toxicology and Mutagenesis ,Radical ,Inorganic chemistry ,0211 other engineering and technologies ,Iron oxide ,02 engineering and technology ,010501 environmental sciences ,01 natural sciences ,Catalysis ,law.invention ,chemistry.chemical_compound ,Reaction rate constant ,law ,Peroxydisulfate ,Biochar ,Environmental Chemistry ,Electron paramagnetic resonance ,Waste Management and Disposal ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Sulfates ,Persulfate ,Pollution ,chemistry ,Charcoal ,Environmental Pollutants ,Oxidation-Reduction ,Water Pollutants, Chemical - Abstract
In this study, the Fe, N co-doped biochar (Fe-N-BC) was prepared by pyrolyzing wheat straw, urea and iron salts and used to activate persulfate (peroxydisulfate, PS) for organic contaminant degradation. Iron oxide doping not only introduced magnetism into the biochar for easy separation, but also influenced its catalytic ability for PS activation. In the Fe-N-BC/PS system, almost all acid orange (AO7) was removed within 90 min with an apparent rate constant (kobs) of 0.114 min−1, which was almost 37 times larger than that of pure N-BC (0.003 min−1). Factors influencing the removal of AO7 were investigated, including PS concentration, catalyst dosage, and initial pH. The Fe-N-BC/PS system had high removal efficiencies for various organic contaminants and showed high resistance to inorganic anions in aquatic environments. The radical quenching studies, electron paramagnetic resonance (EPR) measurements, and electrochemical analyses verified that the mechanism of AO7 degradation in the Fe-N-BC/PS system included both radical and non-radical pathways involving the generation of OH, SO4− , O2− , 1O2, and electron transfer. Additionally, persistent free radicals (PFRs) on the catalysts also related to their catalytic efficiencies. These results demonstrated that the Fe-N-BC/PS system had the potential for wastewater treatment applications.
- Published
- 2020
30. PM2.5 levels, chemical composition and health risk assessment in Xinxiang, a seriously air-polluted city in North China
- Author
-
Shuhui Liu, Xianfa Su, Yuepeng Pan, Hao Yu, Jianhui Sun, Jinglan Feng, and Yi Li
- Subjects
Pollution ,Environmental Engineering ,Haze ,010504 meteorology & atmospheric sciences ,media_common.quotation_subject ,Air pollution ,Coal combustion products ,010501 environmental sciences ,medicine.disease_cause ,complex mixtures ,01 natural sciences ,Geochemistry and Petrology ,medicine ,Environmental Chemistry ,Chemical composition ,Air quality index ,0105 earth and related environmental sciences ,General Environmental Science ,Water Science and Technology ,media_common ,Total organic carbon ,Health risk assessment ,Environmental engineering ,General Medicine ,Environmental chemistry ,Environmental science - Abstract
Seventeen PM2.5 samples were collected at Xinxiang during winter in 2014. Nine water-soluble ions, 19 trace elements and eight fractions of carbonaceous species in PM2.5 were analyzed. PM2.5 concentrations and elements species during different periods with different pollution situations were compared. The threat of heavy metals in PM2.5 was assessed using incremental lifetime cancer risk. During the whole period, serious regional haze pollution persisted, and the averaged concentration of PM2.5 was 168.5 μg m−3, with 88.2 % of the daily samples exhibiting higher PM2.5 concentrations than the national air quality standard II. The high NO3 −/SO4 2− ratio suggested that vehicular exhaust made an important contribution to atmospheric pollution. All of organic carbon and elemental carbon ratios in this study were above 2.0 for PM2.5, which might reflect the combined contributions from coal combustion, motor vehicle exhaust and biomass burning. Mean 96-h backward trajectory clusters indicated that more serious air pollution occurred when air masses transported from the Hebei, Shanxi and Zhengzhou. The concentrations of the water-soluble ions and trace elements on haze days were 2 and 1.8 times of those on clear days. The heavy metals in PM2.5 might not cause non-cancerous health issues by exposure through the human respiratory system. However, lifetime cancer risks of heavy metals obviously exceeded the threshold (10−6) and might have a cancer risk for residents in Xinxiang. This study provided detailed composition data and comprehensive analysis of PM2.5 during the serious haze pollution period and their potential impact on human health in Xinxiang.
- Published
- 2016
31. Impact of internal recycle ratio on nitrous oxide generation from anaerobic/anoxic/oxic biological nitrogen removal process
- Author
-
Yan Xu, Qilu Li, Yunping Han, Jianhui Sun, and Xianfa Su
- Subjects
education.field_of_study ,Environmental Engineering ,Denitrification ,0208 environmental biotechnology ,Inorganic chemistry ,Population ,Biomedical Engineering ,Bioengineering ,Nitrous-oxide reductase ,02 engineering and technology ,Nitrous oxide ,010501 environmental sciences ,Nitrite reductase ,01 natural sciences ,Anoxic waters ,020801 environmental engineering ,chemistry.chemical_compound ,chemistry ,Nitrate ,Environmental chemistry ,Aerobic denitrification ,education ,0105 earth and related environmental sciences ,Biotechnology - Abstract
To evaluate the effects of internal recycle ratio on nitrous oxide (N 2 O) generation, we set up three laboratory-scale anaerobic–anoxic–oxic (A 2 O) wastewater treatment processes, with internal recycle ratios of 100%, 200%, and 300%, respectively. Total nitrogen (TN) removal was markedly enhanced from 45.8% to 61.9%, as the internal recycle ratio increased from 100% to 300%. N 2 O generation was increased from 3.47 to 9.81 × 10 −2 mg/L during the treatment process, with the anoxic section showing the largest N 2 O increment from denitrification. This phenomenon is attributed to the increased amount of nitrate (NO 3 − -N) substrate available for denitrification, due to the increased volume of internal recycle liquid, as well as the increased amount of oxygen, which could restrain the activity of nitrous oxide reductase brought to the anoxic section. Nitrous oxide reductase was more sensitive to oxygen than nitrate and nitrite reductases. Microorganism analysis indicated that the population of nosZ gene-containing bacteria was only slightly affected by the recycle ratio. However, the number of nosZ gene copies decreased as the internal recycle ratio increased from 100% to 300%; this result reveals noticeable decreases in the denitrification capacity of the system for reducing N 2 O to N 2 .
- Published
- 2016
32. Seasonal and Particle Size-Dependent Variations of Hexabromocyclododecanes in Settled Dust: Implications for Sampling
- Author
-
Jinglan Feng, Adrian Covaci, Jian-hui Sun, Gang Yu, Xianfa Su, Wenchao Li, Zhiguo Cao, Fuchao Xu, and Mohai Shen
- Subjects
Road dust ,China ,Dust sample ,Dust particles ,medicine ,Humans ,Environmental Chemistry ,Particle Size ,Workplace ,Biology ,Analytic Sample Preparation Methods ,Sampling (statistics) ,Dust ,Stereoisomerism ,General Chemistry ,Contamination ,Seasonality ,medicine.disease ,Hydrocarbons, Brominated ,Chemistry ,13. Climate action ,Environmental chemistry ,Environmental science ,Environmental Pollutants ,Seasons ,Particle size - Abstract
Particle size is a significant parameter which determines the environmental fate and the behavior of dust particles and, implicitly, the exposure risk of humans to particle-bound contaminants. Currently, the influence of dust particle size on the occurrence and seasonal variation of hexabromocyclododecanes (HBCDs) remains unclear. While HBCDs are now restricted by the Stockholm Convention, information regarding HBCD contamination in indoor dust in China is still limited. We analyzed composite dust samples from offices (n = 22), hotels (n = 3), kindergartens (n = 2), dormitories (n = 40), and main roads (n = 10). Each composite dust sample (one per type of microenvironment) was fractionated into 9 fractions (F1-F9: 2000-900, 900-500, 500-400, 400-300, 300-200, 200-100, 100-74, 74-50, and
- Published
- 2015
33. One year study of PM
- Author
-
Jinglan, Feng, Hao, Yu, Kai, Mi, Xianfa, Su, Yi, Li, Qilu, Li, and Jianhui, Sun
- Subjects
Aerosols ,Air Pollutants ,China ,Air Pollution ,Particulate Matter ,Seasons ,Cities ,Particle Size ,Environmental Monitoring ,Vehicle Emissions - Abstract
This study was conducted in order to explore the seasonal characteristics, climate impact and source of PM
- Published
- 2017
34. The pollution characteristics of PM
- Author
-
Jinglan, Feng, Hao, Yu, Kai, Mi, Xianfa, Su, Yunqi, Chen, Jian-Hui, Sun, and Qilu, Li
- Subjects
Aerosols ,Quality Control ,China ,Fossil Fuels ,Solubility ,Politics ,Particulate Matter ,Congresses as Topic ,Particle Size ,Weather ,Carbon ,Vehicle Emissions - Abstract
The pollution characteristics of PM
- Published
- 2017
35. PM
- Author
-
Jinglan, Feng, Hao, Yu, Shuhui, Liu, Xianfa, Su, Yi, Li, Yuepeng, Pan, and Jianhui, Sun
- Subjects
Air Pollutants ,China ,Neoplasms ,Humans ,Particulate Matter ,Environmental Exposure ,Cities ,Particle Size ,Risk Assessment ,Environmental Monitoring - Abstract
Seventeen PM
- Published
- 2016
36. Effect of mixed liquor suspended solid concentration on nitrous oxide emission from an anoxic/oxic sequencing bioreactor.
- Author
-
Xu Yan, Dongli Guo, Dezhi Qiu, Shikan Zheng, Mengke Jia, Mengjiao Zhang, Jingjing Liu, Xianfa Su, and Jianhui Sun
- Abstract
Generation of nitrous oxide (N
2 O), which is a strong greenhouse gas, during the biological nitrogen removal process in wastewater treatment plants has attracted widespread attention in recent years. However, the effect of mixed liquor suspended solid (MLSS) concentration on N2 O generation is poorly understood. We analyzed the N2 O emissions from three parallel anoxic/oxic biological nitrogen removal treatment systems in which the initial MLSS concentrations were 2,000 ± 100, 3,000 ± 100, and 4,000 ± 100 mg/L and the activated sludge loads were identical. The activated sludge properties and microbial community characteristics were also studied. It was found that as the initial MLSS concentration increased, the chemical oxygen demand (COD) as well as the total nitrogen, and total phosphorus removal efficiencies increased, while the nitrification rate decreased. N2 O–N conversion rates of 2.7%, 3.5%, and 4.1% corresponded to systems whose initial MLSS concentrations were 2,000 ± 100, 3,000 ± 100, and 4,000 ± 100 mg/L, respectively. The polyhydroxyalkanoate (PHA) and extracellular polymeric substance contents in the activated sludge were positively correlated with the initial MLSS concentration. The particle size distribution of the activated sludge flocs (ASFs) also varied under different MLSS concentrations; the proportion of large ASFs increased slightly as the initial MLSS concentration increased. High-throughput sequencing results showed that the bacterial species richness and microbial population diversity were enhanced as the initial MLSS concentration was increased. The relative abundance of the ammonia-oxidizing bacteria Nitrosomonas and Sphingomonas decreased while the total relative abundance of the denitrification bacteria with Caldilinea, Ignavibacterium, Solitalea, Steroidobacter, Thauera, Comamonas, Lysobacter, and Rhodobacter increased as the initial MLSS concentration increased. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
37. Seasonal and Particle Size-Dependent Variations of Hexabromocyclododecanes in Settled Dust: Implications for Sampling.
- Author
-
Zhiguo Cao, Fuchao Xu, Wenchao Li, Jianhui Sun, Shen, Mohai, Xianfa Su, Jinglan Feng, Gang Yu, and Covaci, Adrian
- Published
- 2015
- Full Text
- View/download PDF
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