FUEL
·
2021
·
IF 6.609
Yong Wei,Guijian Liu,Biao Fu,Yuan Liu,Xuan Xue
Fine particulate matter (PM) emitted from coal-fired power plants (CFPPs) has aroused widespread environmental and human health concerns. Cadmium (Cd), as one of the prime toxic air pollutants, which exists in fine PM intensifies its toxicity. In this research, three particle sizes of PM (PM 1 , PM 2.5 , and PM 10 ) at the outlet of electrostatic precipitator (ESP), along with feed coal, bottom ash, and ESP ash, were collected from a 300-MW pulverized CFPP. Results showed that Cd was more enriched in the fly ash than in bottom ash. With the PM diameter decreasing, the relative enrichment index (REI) value of Cd increases from 2.30 to 7.84. The concentration of Cd was found to be intimately related to Ti in the PM. Abundant Ti-rich particles were identified in the PM 1 , having quite different chemical compositions as compared to particles larger than 2.5 μm. The major processes governing the formation of Ti-rich particles included melting of silicate-bound Ti and heterogeneous condensation of gaseous Ti from the decomposition of organic-associated Ti in coal. The transformation behavior of Cd to PM in a coal combustion process was discussed based on its occurrence mode in coal, thermodynamic property, and the possible interactions with ash particle compositions. The retention of Cd (g) by Ti-rich particle were probably dominated by chemisorption at high temperature; at lower temperature, physical adsorption or condensation may be the primary mechanisms for capturing CdCl 2 (g).
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Yiquan Guo,Junying Zhang,Yongchun Zhao,Shaolong Wang,Cheng Jiang,Chuguang Zheng
Fly ash fine particles emitted from coal-fired power plants are the primary atmospheric pollutant in China. The pressure, temperature, and velocity distribution of the flow field in a chamber was simulated to evaluate chemical agglomeration. The effect on the removal efficiency of composition, concentration, pH, K + content, and zeta potential of the chemical agglomeration solutions as well as surfactant and flue gas temperature were evaluated. The results suggested that suitable solutions could significantly improve the removal efficiency of fine particles. Among these, kappa-carrageenan performed best and achieved a removal efficiency of 47.1%. Synergism was detected as two different chemical agglomeration solutions were mixed together: a mixture of kappa-carrageenan and konjac glucomannan attained a removal efficiency of 59.3%, higher than their individual values. The efficiency improved initially and then decreased as the solution K + concentration increased. Also surfactants affected agglomeration: cationic and non-ionic surfactants enlarged the removal efficiency by 9.0% and 3.7%, respectively, whereas anionic surfactants lessened average removal efficiency by 5.6%. Zeta potential influenced the removal efficiency as well: it peaked as the zeta potential was around 0 mV.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Yong Wei,Guijian Liu,Biao Fu,Ruwei Wang,Yuan Liu,Xuan Xue,Mei Sun
Inhalable fine particulate matter (PM), which is rich in Pb and other pollutants from coal-fired power plants, can cause air pollution and severe health problems. To facilitate the development of efficient techniques for controlling fine particulate Pb emissions, in this study, various types of size-resolved fine PM (<10.0 μm) were collected from the outlets of fabric filter units (FFs) at an industrial circulating fluidized bed (CFB) power plant to assess the distribution and partitioning behavior of Pb. The results showed that the mass particle size distribution (PSD) of the collected fine PM followed unimodal distribution, peaking at 5.8–4.7 μm, which might be caused by the fragmentation of limestone additives and new-formed CaSO 4 . However, the mass PSD of Pb for size-fractionated PM displayed different distribution pattern. Two peaks were observed in the size ranges of 5.8–4.7 μm and 1.1–0.7 μm. The mechanism of Pb enrichment in the supermicron particles was mainly controlled by the surface adsorption reaction, which could be explained by 1/d p dependence and be improved using excess active CaO produced by the injected limestone. For submicron particles, gas-film transfer or heterogenous condensation (mass transfer) might represent the deposition mechanism . Besides Pb enrichment, it was found that the submicron particles (<0.7 μm) mainly consisted of Si-rich and Si–Al phases. The emission of those fine SiO 2 -bearing particles should be limited as they can be inhaled and can damage the respiratory system.
研究领域:
环境科学
·
公共卫生
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2022
·
IF 5.64
Jie Yin,Jun Zhang,Li Lv,Hui Zhong
Heterogeneous condensation preconditioning technology has generated broad interest in removing fine particles from coal-fired flue gas due to its economic and environmental advantages. Here, a flow cloud chamber was used to study the effect of 0%–90% CO 2 concentrations on the growth performance of insoluble fine particles with different operational conditions. The results suggest that a higher CO 2 concentration in the particle growth environment is detrimental to the fine particles growth. The higher the CO 2 concentration, the worse the growth performance. The adverse effect of CO 2 on the growth performance decreases with the increase of growth time and the increase of supersaturation caused by temperature, and does not change significantly with the increasing particle concentration.
研究领域:
环境科学
·
大气科学
✓ 已验证
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Yiquan Guo,Yongchun Zhao,Shaolong Wang,Cheng Jiang,Junying Zhang
Fly ash fine particles emitted from flue gas during coal combustion are the primary atmospheric pollutants in China. The purpose of this study was to investigate the characteristics of the zeta potential of fine particle suspensions. The relationship between the zeta potential and the fine particle removal efficiency was also discussed. Batch experiments were conducted to evaluate the zeta potential of fine particle aqueous solutions under various pH, ion concentration, surfactant, polymer, and chemical agglomeration solution conditions. A chemical agglomeration system was designed to simulate the removal process of the fine particles. The test results indicated that the zeta potential absolute value of the solution decreased initially and then increased as the pH increased. As the pH increased from 4 to 12, the zeta potential decreased from Zp = 9.4 mV to Zp = −45.4 mV. The isoelectric point (IEP) was 4.3. Also at the IEP, the highest fine particle removal efficiency of 25.9% was achieved. The zeta potential increased as the metal cation concentration of the solutions increased. The trivalent cation Al 3+ exhibited the best performance, which increased Zp from −32.1 mV to −11.2 mV and produced the highest fine particle removal efficiency of 9.2%. Polymers significantly impacted the zeta potential. As the concentration of kappa-carrageenan (CAR) increased from 0.01% to 5%, the zeta potential increased from −30.1 mV to 12.6 mV. The highest fine particle removal efficiency of 41.8% was acquired at a concentration of 0.5%, which had the lowest zeta potential absolute value of 3.5 mV. It can be inferred that the increase in the zeta potential induced the growth of the energy barrier, which prevented particle agglomeration. The suspension with a lower zeta potential exhibited a better fine particle removal efficiency.
研究领域:
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2018
·
IF 6.653
Qingcai Chen,Haoyao Sun,Mamin Wang,Zhen Mu,Yuqin Wang,Yanguang Li,Yansong Wang,Lixin Zhang,Zimeng Zhang
To understand the nature and possible sources of environmentally persistent free radicals (EPFRs) in atmospheric aerosols, the present study used a solvent extraction method to fractionate aerosol components with different polarities and solvent resistance in fine particulate matter (PM2.5) from Xi’an, China. The characteristics of EPFRs, that is., their concentration, type and lifetime, were obtained based on their electron paramagnetic resonance spectra. The results showed that the EPFRs in the PM2.5 samples were carbon-centered with a nearby heteroatom (g = 2.0031) and had a long half-life of more than 3 years. Nearly all of the extractable EPFRs were detected in the water-insoluble organic fraction and showed characteristics indicating that may contain oxygen-centered radical (g = 2.0038). Most of the total EPFRs in the PM2.5 were derived from solvent-resistant organic matter (88%), which likely consisted of graphene oxide analogues. The results suggest that previous studies may have missed the major proportion of EPFRs in atmospheric particulates if they only focused on solvent-extractable or metallic oxide-formed EPFRs. Our results showed that the EPFR concentration was significantly and positively correlated with the elemental carbon and NO2 concentrations, suggesting that traffic emissions may be an important source of EPFRs in PM2.5 over Xi’an.
研究领域:
环境科学
·
大气化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Yanhao Zhang,Zifang Peng,Peiru Luo,Lin Zhu,Qingyun He,Congcong Pei,Dan Yin,Wenfen Zhang,Shusheng Zhang,Zongwei Cai
The broad application of various pesticides guarantees the development of agriculture all over the word but has ultimately led to their ubiquitous release into the environment as hazardous chemical residues. Diamide insecticides (DAIs) are regarded as new choice for prevention and protection of agricultural crops and city landscaping plants from the pests in more and more countries. However, their presence in fine particulate matter (PM 2.5 ) and associated health risks have not been studied. We reported for the first time the extensive distributions of PM 2.5 -bound DAIs in rural and urban areas of China, one of the world’s largest agricultural countries. Eight DAIs were analyzed, and five were consistently detected in PM 2.5 samples at concentrations primarily of pg m −3 level. Evident spatial/temporal variations were observed, with generally more serious DAIs’ contamination and long-term health risks in rural areas during spring, summer and autumn. The first exploration of DAIs’ toxicities on human bronchial epithelial cells discovered their capability of inhibiting cell viabilities, further demonstrating the potential detrimental effects of these emerging pollutants in PM 2.5 . This study confirms the widespread appearance of DAIs in PM 2.5 , emphasizing the need and urgency for concern about their pollution in both rural and urban air.
研究领域:
环境科学
·
毒理学
·
公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 33
·17482-17491
·
IF 8.867
Zhi-Chao Xiong,Ri-Long Yang,Ying-Jie Zhu,Fei-Fei Chen,Li-Ying Dong
Fine particulate matter (PM) air pollution has been attracting much attention due to its great threat to human health. Herein, we report a new kind of air filter paper with high removal efficiencies for PM2.5 and PM10 prepared using ultralong hydroxyapatite (HAP) nanowires and cotton (CT) fibers as building blocks through a simple vacuum filtration process. Flexible and biocompatible ultralong HAP nanowires with lengths over 200 μm and diameters of approximately 20 nm are employed for significant improvement of the air filtration performance of commercial CT fibers. The ultralong HAP nanowires intertwine with CT fibers and form the highly porous HAP/CT air filter paper. In addition, by optimizing the proportion of HAP and CT, the as-prepared HAP/CT air filter paper exhibits high removal efficiencies of over 95% for PM2.5 and PM10; more importantly, it shows a lower pressure drop and a smaller thickness than a commercial breathing mask. Moreover, the fabrication of a large-sized HAP/CT air filter paper with desirable properties through a commercial sheet former is demonstrated. As a proof-of-concept, a homemade breathing mask is fabricated by imbedding the HAP/CT air filter paper into a commercial breathing mask. Furthermore, benefiting from the unique characteristics of ultralong HAP nanowires, other functions such as antibacterial activity can be achieved by the immobilization of silver nanoparticles as the representative bactericide, enabling the fabrication of multifunctional air filter paper. The experimental results suggest that the ultralong HAP nanowire-based air filter paper is promising for various applications in the environmental field.
研究领域:
环境科学
·
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2023
·
IF 9.5
Mengke Tang,Liang Jiang,Cunmin Wang,Xinyu Li,Xinjian He,Yichen Li,Changhui Liu,Yanqing Wang,Jiefeng Gao,Huan Xu
Despite the great potential in fabrication of biodegradable and eco-friendly air filters by electrospinning poly(lactic acid) (PLA) membranes, the filtering performance is frequently dwarfed by inadequate physical sieving or electrostatic adsorption mechanisms to capture airborne particulate matters (PMs). Here, using the parallel spinning approach, the unique micro/nanoscale architecture was established by conjugation of neighboring PLA nanofibers, creating bimodal fibers in electrospun PLA membranes for the enhanced slip effect to significantly reduce the air resistance. Moreover, the bone-like nanocrystalline hydroxyapatite bioelectret (HABE) was exploited to enhance the dielectric and polarization properties of electrospun PLA, accompanied by the controlled generation of junctions induced by the microaggregation of HABE (10–30 wt %). The incorporated HABE was supposed to orderly align in the applied E-field and largely promote the charging capability and surface potential, gradually increasing to 7.2 kV from the lowest level of 2.5 kV for pure PLA. This was mainly attributed to HABE-induced orientation of PLA backbone chains and C═O dipoles, as well as the interfacial charges trapped at the interphases of HABE–PLA and crystalline region–amorphous PLA. Given the multiple capturing mechanisms, the micro/nanostructured PLA/HABE membranes were characterized by excellent and sustainable filtering performance, e.g., the filtration efficiency of PM0.3 was promoted from 59.38% for pure PLA to 94.38% after addition of 30 wt % HABE at a moderate airflow capacity of 32 L/min and from 30.78 to 83.75% at the highest level of 85 L/min. It is of interest that the pressure drop was significantly decreased, mainly arising from the slip effect between the ultrafine nanofibers and conjugated microfibers. The proposed combination of the nanostructured electret and the multistructuring strategy offers the function integration of efficient filtration and low resistance that are highly useful to pursue fully biodegradable filters.
研究领域:
材料科学
·
环境科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Applied Spectroscopy
·
2019
·Vol. 86
·期 1
·89-95
·
IF 0.675
Wang Haojiang,Wang Xuan,Bian Wei,Sun Tijian,Cai Zongwei,Wei Jiancong
Core-shell magnetic metal organic nanocrystals were synthesized and used as matrix for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Four nitropolycyclic aromatic hydrocarbons (nitro-PAHs) were successfully detected by using negative-ion MALDI-TOF MS without background interference. Furthermore, the magnetic nanocomposites (MNCs) coated with zeolitic imidazolate framework-8 (ZIF-8) showed excellent adsorption and enrichment capacity, and can be isolated with a magnet and directly spotted on the stainless steel plate for MALDI measurement. It was also analyzed nitro-PAHs in PM2.5 samples using the ZIF-8-coated magnetic nanocomposite as adsorbent and matrix.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2015
·
IF 4.169
Liang Hao,Dapeng Wu,Kun Ding,Hu Meng,Xiaohui Yan,Yafeng Guan
Thermal desorption–gas chromatography–mass spectrometer (TD–GC–MS) technique has been widely used for analysis of semi-violate organic compounds on atmospheric aerosol . To prevent GC column from being damaged by fine solid particles during thermal desorption process, glass wool as filter mat is indispensible. However, the filtration efficiency has never been validated. In this paper, the most penetrating particle size and the minimum packing thickness of glass wool were calculated based on classical filtration theory. According to the calculation results, packing parameters of glass wool were optimized experimentally using silica particles. It is demonstrated that glass wool with a packing thickness of 30 mm, solidity of 0.039 can effectively block these fine solid particles from penetrating at normal thermal desorption conditions ( T = 300 °C, u = 0.4–4 cm/s). Finally, the filtration efficiency of glass wool was further confirmed with real PM2.5 samples. Under the validated filtration condition, TD–GC–MS was applied for the analysis of non-polar organic compounds on real PM2.5 samples, and very good results were obtained.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Fanglin Shen,Dan Li,Jianmin Chen
Fuel exhaust particulate matter (FEPM) is an important source of air pollution worldwide. However, the comparative and mechanistic toxicity of FEPMs emitted from combustion of different fuels is still not fully understood. This study employed pathway-based approaches via human cells to evaluate mechanistic toxicity of FEPMs. The results showed that FEPMs caused concentration-dependent (0.1–200 μg/mL) cytotoxicity and oxidative stress. FEPMs at low concentration (10 μg/mL) induced cell cycle arrest in S and G2 phases, while high level of FEPMs (200 μg/mL) caused cell cycle arrest in G1 phase. Different FEPMs induced distinct expression profiles of toxicity-related genes, illustrating different toxic mechanisms. Furthermore, FEPMs inhibited the phosphorylation of protein kinase A (PKA), which related with reproductive toxicity. Spearman rank correlations among the chemicals carried by FEPMs and the toxic effects revealed that PAHs and metals promoted cell cycle arrest in the G1 phase and suppressed PKA activity. Furthermore, PAHs (Nap and Acy) and metals (Al and Pb) in FEPMs were highly and positively correlated with the expression of genes involved in apoptosis, ER stress, metal stress and inflammation. Our findings offered more mechanistic information of FEPMs at the level of subcellular toxicity and help to better understand their potential health effects.
研究领域:
环境科学
·
毒理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）