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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121884, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36179563

RESUMO

The AIE bio-probes have attracted extensive attention because of their good brightness, long-term in situ retention ability, photostability and low cytotoxicity. Recently, the transformation of ACQ to AIE has become very popular, which is very important for the further development of AIE probes. Herein, a series of novel dyes (NR-Lyso-Ⅰ, NR-Lyso-Ⅱ, NR-Lyso-III, NR-Lyso-IV) were designed and synthesized. It was found that alkylation of 4-aminonaphthalimide could achieve the transformation of the dye from ACQ to AIE effect due to the growth of carbon chain. Moreover, the AIE probe NR-Lyso-IV exhibited dual-state emission (DSE) and large Stokes shift (>100 nm), excellent selectivity, photostability, and low cytotoxicity, which was able to simultaneous visualize the lipid droplets (LDs) and lysosomes of HeLa cells and zebrafish.


Assuntos
Corantes Fluorescentes , Gotículas Lipídicas , Humanos , Animais , Células HeLa , Peixe-Zebra , Lisossomos
2.
Chemosphere ; 298: 134222, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35259365

RESUMO

Pharmaceuticals residual in the human urine are difficult to remove in the conventional wastewater treatment plants (WWTPs) and cause a serious environmental issue. Hence, we developed a FeOCl-coated ceramic membrane coupled with the Photo-Fenton system for direct removing pharmaceuticals from human urine. In this study, the removal efficiency of CBZ from hydrolyzed urine was higher than that from fresh urine. The apparent rate constant (kobs) of CBZ from hydrolyzed urine could reach 0.0163 min-1, 1.39 times higher than that from fresh urine (0.0117 min-1). Interestingly, this performance was not caused by the solution pH. The effect of substrates in the hydrolyzed urine was further explored, verifying that ammonia played a key role in quenching the hydroxyl radicals (•OH). The nitrogen reactive species (RNS) were then generated, resulting in that the kobs of CBZ from hydrolyzed urine sharply decreased, compared with the phosphate buffer solution (pH = 9). The quenching experiment was further to confirm that the RNS was primary reactive oxide species in the hydrolyzed urine. Based on the data of kinetic study and reported previously, competitive kinetic modeling was set up, which could successfully predict the removal efficiency of pharmaceuticals from hydrolyzed urine. The study provided a new method for removing pharmaceuticals residual in human urine and the kinetic modeling could be widely used to predict the removal of pharmaceuticals from human urine.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Carbamazepina , Cerâmica , Humanos , Cinética , Oxirredução , Preparações Farmacêuticas , Poluentes Químicos da Água/análise
3.
Org Lett ; 24(6): 1323-1328, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35129353

RESUMO

An efficient PhIO-mediated oxidative C═C bond cleavage and reassembly of enaminone toward oxazolone with high regioselectivity has been reported. DFT calculations revealed that the reaction proceeded through an oxygen atom transfer, C═C bond cleavage, alkylthio migration, and reassembly cascade. This strategy is highlighted by high atom and step economy with formation of five bonds in one pot and generation of a high-valued oxazolone skeleton under mild conditions.

4.
J Hazard Mater ; 419: 126452, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198220

RESUMO

To enable efficient degradation of perfluorooctanoic acid (PFOA), we prepared and investigated a nanosheet photocatalyst (Pt/La2Ti2O7). Doping platinum nanoparticles on La2Ti2O7 varied the band structure and improved the photocatalytic activity due to the enhanced charge separation. Methanol as the electron donor and sacrificial reagent significantly promoted the photocatalytically reductive degradation of PFOA that reduced by 40% within 180 min under UV254 irradiation (1 mW∙cm2). The density functional theory calculations were used to analyze the effects of Pt doping and band structures on interfacial electron transfer and degradation pathways. As opposed to photocatalytic oxidation, this UV/Pt/La2Ti2O7/CH3OH photocatalysis could abstract electrons from methanol and convert to free reactive radicals and photo-generated electrons to reductively defluorinate PFOA and potentially other polyhalogenated or perhalogenated organic compounds.

5.
Adv Colloid Interface Sci ; 282: 102207, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32688044

RESUMO

Catalytic membranes combine catalytic activity with conventional filtration membranes, thus enabling diverse attractive benefits into the conventional membrane filtration processes, such as easy catalyst reuse, antifouling, anti-microbial, and enhancing process efficiency. Up to date, tremendous progresses have been made on functional catalytic membrane preparation and applications, which significantly advances the competitiveness of membrane technologies in process industries. The present article provides a critical and holistic overview of the current state of knowledge on existing catalyst coating techniques for functional catalytic membrane development. Based on coating mechanisms, the techniques are generally categorized into physical and chemical surface coating routes. For each technique, we first introduce fundamental principle, followed by a critical discussion of their applications with representative case studies. Advantages and drawbacks are also emphasized for different surface coating technologies. Finally, future perspectives are highlighted to provide deep insights into their future developments.

6.
Sci Total Environ ; 722: 137657, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32199356

RESUMO

The treatment of sewage with high-nitrogen/-phosphorus and low-carbon remains a challenge. A novel iron-carbon galvanic cells strengthened anaerobic/anoxic/oxic process (Fe/C-A2O) was developed for high-nitrogen/-phosphorus and low-carbon sewage treatment. The cost-effective iron-scraps (ISs) was recycled as Fe(0)-source under the mediation of Fe/C galvanic cell reaction to develop effective Fe(0)-oxidizing autotrophic-denitrification and -dephosphorization. Utilizing practical high-nitrogen/-phosphorus and low-carbon sewage as target wastewater, the performance, impact factors, contribution of Fe/C galvanic cell reactions, microbial characteristics, strengthening mechanisms, and application potential of Fe/C-A2O process were investigated. The Fe/C-A2O process achieved high TN and TP removal efficiencies of 92.0 ± 1.3% and 97.2 ± 0.9% with removal loads of 0.176 ± 0.002 kg TN/(m3·d) and 0.017 ± 0.002 kg TP/(m3·d), respectively. Optimal HRT of 12 h, DO of 4.0-4.5 mg/L, and reflux-ratio of 4:1 were obtained, and no sludge-reflux was required. Autotrophic-denitrification and -dephosphorization supported by the Fe/C galvanic cell reactions contributed 63.1% and 75.3% of TN and TP removal, respectively. Microbial characterization revealed the dominance of autotrophic denitrifiers (e.g., Thiobacillus), AOB (e.g., Nitrosomonas), NOB (e.g., Nitrospira), and heterotrophic denitrifiers (e.g., Zoogloea). The mechanism analysis demonstrated that Fe/C galvanic cells strengthened nitrogen removal by raising Fe2+/H2-supported autotrophic denitrification; and strengthened dephosphorization by introducing Fe3+-based PO43--precipitation and enhancing the denitrifying phosphate-accumulation by denitrifying phosphate-accumulating organisms (DPAOs). Based on the efficiency and cost evaluation, the ISs-based Fe/C-A2O process showed significant application potential as an upgrade strategy for traditional A2O process in advanced high-nitrogen/phosphorus and low-carbon sewage treatment.


Assuntos
Esgotos , Anaerobiose , Reatores Biológicos , Carbono , Desnitrificação , Ferro , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos , Águas Residuárias
7.
Sci Total Environ ; 711: 135087, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000338

RESUMO

Oxygen has not been purposely introduced to the autotrophic denitrification systems and simultaneous nitrification/autotrophic denitrification (SNAD) has not been proposed. In this study, oxygen was introduced into a micro-electrolysis-enhanced Fe0-supported autotrophic denitrification (mFe0AD) system. The nitrogen removal performance was investigated and the application potential of iron-scraps-supported simultaneous nitrification/mFe0AD was evaluated. The results showed that Fe0AD was surprisingly enhanced by oxygen together with nitrification at average dissolved oxygen (DO) of 0.08-1.56 mg/L. The ammonia oxidizing bacterial, nitrite oxidizing bacteria, facultative autotrophic denitrificans, and iron compounds transformation bacteria were markedly enriched. Average denitrification rate shifted from 0.116 to 0.340 kg N/(m3·d) with increase of average total nitrogen removal efficiency from 31.4% to 90.5%. Oxygen could enhance the biological conversion and storage of iron compounds, which was capable of reducing the coating of Fe0 surface.The accelerating of oxygen on  Fe0 passivation appeared when increasing the average DO from 1.56 to 2.17 mg/L. Therefore, the SNAD was recommended to be operated at the DO range of 0.08-1.56 mg/L. ME significantly enhanced Fe0AD, and the utilization of iron-scraps reduced its cost. The denitrification rate is comparable with methanol supported heterotrophic denitrification with 58.9% reduction on the cost. The iron-scraps supported SNAD is competitive in both denitrification rate and costs in the ammonia contaminated low-carbon water treatment.


Assuntos
Desnitrificação , Nitrificação , Reatores Biológicos , Eletrólise , Ferro , Nitrogênio , Oxigênio
8.
Nanomaterials (Basel) ; 10(1)2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31968619

RESUMO

Pharmaceutical residuals are increasingly detected in natural waters, which made great threat to the health of the public. This study evaluated the utility of the photo-Fenton ceramic membrane filtration toward the removal and degradation of sulfamethoxazole (SMX) as a model recalcitrant micropollutant. The photo-Fenton catalyst Goethite (α-FeOOH) was coated on planar ceramic membranes as we reported previously. The removal of SMX in both simulated and real toilet wastewater were assessed by filtering the feed solutions with/without H2O2 and UV irradiation. The SMX degradation rate reached 87% and 92% respectively in the presence of UV/H2O2 for the original toilet wastewater (0.8 ± 0.05 ppb) and toilet wastewater with a spiked SMX concentration of 100 ppb. The mineralization and degradation by-products were both assessed under different degradation conditions to achieve deeper insight into the degradation mechanisms during this photo-Fenton reactive membrane filtration. Results showed that a negligible removal rate (e.g., 3%) of SMX was obtained when only filtering the feed solution through uncoated or catalyst-coated membranes. However, the removal rates of SMX were significantly increased to 67% (no H2O2) and 90% (with H2O2) under UV irradiation, respectively, confirming that photo-Fenton reactions played the key role in the degradation/mineralization process. The highest apparent quantum yield (AQY) reached up to approximately 27% when the H2O2 was 10 mmol·L-1 and UV254 intensity was 100 µW·cm-2. This study lays the groundwork for reactive membrane filtration to tackle the issues from micropollution.

9.
J Hazard Mater ; 386: 121955, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887563

RESUMO

Micropollution such as pharmaceutical residuals potentially compromises water quality and jeopardizes human health. This study evaluated the photo-Fenton ceramic membrane filtration toward the removal of sulfadiazine (SDZ) as a common antibiotic chemical. The batch experiments verified that the photo-Fenton reactions with as Goethite (α-FeOOH) as the photo-Fenton catalyst achieved the degradation rates of 100% within 60 min with an initial SDZ concentration of 12 mg·L-1. Meanwhile, a mineralization rate of over 80% was obtained. In continuous filtration, a negligible removal rate (e.g., 4%) of SDZ was obtained when only filtering the feed solution with uncoated or catalyst-coated membranes. However, under Ultraviolet (UV) irradiation, both the removal rates of SDZ were significantly increased to 70% (no H2O2) and 99% (with H2O2), respectively, confirming the active degradation by the photo-Fenton reactions. The highest apparent quantum yield (AQY) reached up to approximately 25% when the UV254 intensity was 100 µW·cm-2 and H2O2 was 10 mmol·L-1. Moreover, the photo-Fenton reaction was shown to effectively mitigate fouling and prevent flux decline. This study demonstrated synchronization of photo-Fenton reactions and membrane filtration to enhance micropollutant degradation. The findings are also important for rationale design and operation of photo-Fenton or photocatalytic membrane filtration systems.


Assuntos
Antibacterianos/análise , Antibacterianos/efeitos da radiação , Cerâmica/química , Compostos de Ferro/química , Membranas Artificiais , Minerais/química , Sulfadiazina/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Filtração , Peróxido de Hidrogênio/química , Modelos Teóricos , Oxirredução , Fotólise , Sulfadiazina/efeitos da radiação , Raios Ultravioleta , Poluentes Químicos da Água/efeitos da radiação
10.
Huan Jing Ke Xue ; 41(1): 368-376, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854939

RESUMO

The Shen-Fu region is an important urban area in northeast China. We report on a study of the distribution of polybrominated diphenyl ethers (PBDEs) in representative topsoil from this region. In the summer of 2016, 72 soil samples from three cities (Shenyang, Fushun, and Shen-Fu New City) were collected, which covered four land use types:urban, rural residential, cultivated, and woodland. We report on the concentrations, compositions, and distributions of 14 PBDEs in soil and explore their sources, and additionally undertake human exposure analysis and health risk assessments. The results showed that the concentration of ∑14PBDEs in the topsoil ranged from 0.279-50.719 ng·g-1(dry weight), with a mean of (10.466±9.246) ng·g-1. The concentrations of PBDEs was ranked for the cities as:Fushun > Shenyang > Shen-Fu New City > background, and for different land use types as:urban land > rural residential land > cultivated land > forest. Deca-PBDE had the highest proportion of all congeners, accounting for 81.25%-89.23% of all PBDEs. Source analysis indicated that commercial Deca-PBDE was the main source, contributing 66.06% of the total Deca-PBDE according to principal component analysis/multiple linear regression (PCA-MLR). Among five different age groups assessed for exposure, children in Fushun had the highest exposure dose:(20.98±25.01) ng·(kg·d)-1. In terms of different land types, the highest exposure dose was for children living in urban areas:(18.54±20.27) ng·(kg·d)-1. The non-oncogenic health risks in the Shen-Fu region are of a relatively low level.


Assuntos
Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Poluentes do Solo/análise , Criança , China , Cidades , Humanos , Medição de Risco
11.
Huan Jing Ke Xue ; 40(7): 3369-3377, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854740

RESUMO

To study the vertical distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in the soils from different land use types during urbanization, three land use types (urban land, cultivated land, and woodland) were selected in the eastern part of Shenyang, where urbanization is occurring rapidly. In each case, five soil samples were obtained from different depths (0-1 m). Change in the concentrations of PAHs, vertical migration factors, and the distribution and sources of PAHs were analyzed in the vertical soil profiles. Total concentrations of PAHs in the different soil type were ordered as follows:city 1 (513.19-12689.04 µg·kg-1); dry field (36.18-7196.10 µg·kg-1); paddy field (70.92-747.53 µg·kg-1); city 2 (19.39-636.47 µg·kg-1); and woodland (4.79-349.24 µg·kg-1). PAHs were mainly trapped in shallow soils in urban and forest land, but can migrate deeper into the soil profile in cultivated land. High-ring PAHs were abundant at depths of 0-30 cm, while low-ring PAHs were abundant deeper in the soil profiles. SOM had a significant effect on the vertical distribution of PAHs, and the physical and chemical properties of PAHs had a significant influence on their migration ability. However, combustion sources from industrial activities and transportation in the region are still considered the main sources of PAHs despite the fact that some low-ring PAHs derive from petroleum product inputs.

12.
Water Res ; 144: 690-698, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30096694

RESUMO

To develop reactive and antifouling membrane filtration systems, a photo-Fenton ceramic membrane was prepared by coating goethite (α-FeOOH) catalysts on a zirconia/titania alumina membrane via a cross-linking method. Scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize α-FeOOH catalysts and the surface coating quality. The cross linker yielded stable covalent binding between catalyst and membrane under room temperature and produced a homogeneous and smooth coating of catalyst on ceramic membranes. Photo-Fenton reactions were initiated with addition of H2O2 under UV irradiation to improve the foulant degradation on membrane surface while filtration. Membrane fouling was simulated by bovine serum albumin (BSA) and humic acid (HA). Our results show that the photo-Fenton reactions on the coated membranes slowed down the fouling kinetics and even reversed the fouling, leading to a stable transmembrane pressure (TMP) over time of filtration, as opposed to a monotonous increase of TMP due to surface fouling. The batch experiments verified that the photo-Fenton reactions achieved the degradation rates of 76% and 86% for HA and BSA respectively within 60 min, with the mineralization rates of over 80% as indicated by the total organic carbon measurement. This study embarks on a novel antifouling membrane filtration process via incorporation of photo-Fenton reactions. The findings are also important for diverse applications of surface fouling mitigation and rationale design of fouling resistant surfaces or materials through photo-Fenton or other catalytic reactions.


Assuntos
Filtração , Peróxido de Hidrogênio , Cerâmica , Substâncias Húmicas , Membranas Artificiais
13.
Sci Rep ; 7(1): 12165, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28939846

RESUMO

By investigating the uptake of 16 priority polycyclic aromatic hydrocarbons (PAHs) and five heavy metals from soils to maize at the farmlands with industrial wastewater irrigation, this study revealed the effects of heavy metals on PAHs uptake in terms of co-contamination. The results of 15 investigated soils showed medium contamination level and the vertical PAHs distribution in soils indicated that 2-3 rings PAHs with low octanol-water partition coefficient (log Kow < 4.5) were easier to transport in soils, causing a great potential risk immigrating to the groundwater. The 3-ring PAHs were most likely to be taken up by maize roots whereas 2- and 4-6 ring PAHs had the lower likelihood. The translocation of PAHs in maize tissues has positive relationship with log Kow less than 4.5, while negatively correlated otherwise. Redundancy analysis indicated the unexpected results that, except for soil PAHs concentration, the PAHs translocation by maize was reduced by Pb uptake, but not significantly affected by soil organic matters, pH or the other four heavy metals (Cr, Cu, Ni and Zn). This study for the first time provides the restricted factors of PAHs and heavy metal acropetal translocation by maize when they co-exist at wastewater irrigation sites.

14.
Artigo em Chinês | MEDLINE | ID: mdl-22164846

RESUMO

In 2010, there were 385 patients with advanced schistosomiasis in Deyang City, with a prevalence rate of 0.02%. Among all the patients, 14 cases were newly discovered, and 62 received medical assistance. It is suggested that the control of advanced schistosomiasis still should be strengthened.


Assuntos
Esquistossomose/epidemiologia , China/epidemiologia , Humanos , Prevalência , Esquistossomose/diagnóstico , Esquistossomose/patologia
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