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1.
Environ Sci Technol ; 58(12): 5567-5577, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38488517

RESUMO

The development of efficient defluorination technology is an important issue because the kind of emerging pollutant of hexafluoropropylene oxide dimer acid (GenX) as an alternative to perfluorooctanoic acid (PFOA) has the higher environmental risks. In the UV/bisulfite system, we first developed a hydrophobic confined α-Fe2O3 nanoparticle layer rich in oxygen vacancies, which accelerated the enrichment of HSO3- and GenX on the surface and pores through electrostatic attraction and hydrophobic interaction, retaining more hydrated electrons (eaq-) and rapidly destroying GenX under UV excitation. Especially, under anaerobic and aerobic conditions, the degradation percentage of GenX obtain nearly 100%, defluorination of GenX to 88 and 57% respectively. It was amazed to find that the three parallel H/F exchange pathways triggered by the rapid reactions of eaq- and GenX, which were unique to anaerobic conditions, improved the efficiency of fluoride removal and weaken the interference of dissolved oxygen and H+. Therefore, this study provided an available material and mechanism for sustainable fluoride removal from wastewater in aerobic and anaerobic conditions.


Assuntos
Poluentes Ambientais , Fluorocarbonos , Poluentes Químicos da Água , Elétrons , Fluoretos , Caprilatos/química
2.
Environ Sci Technol ; 56(8): 5020-5028, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35383459

RESUMO

Microplastics (MPs) in soils may be ingested by terrestrial animals. While the application of bioplastics is increasing, the ingestion and excretion characteristics of bio-MPs by terrestrial animals are poorly understood as compared to fossil-MPs. Here, the approach-avoidance behavior of adult earthworms Eisenia fetida to MP-contaminated soil was assessed. Fossil-based poly(ethylene terephthalate) (PET) and bio-based poly(lactic acid) (PLA) MPs were found to be preferred by the earthworms, which might be due to the odor of polymer monomers. MPs in earthworm casts were analyzed by microscopy counting and liquid chromatography-tandem mass spectrometry. The amount of microscopically recognizable excreted PET and PLA was 553 and 261 items/g, respectively, while a higher proportion of smaller PLA particles also presented. Bio-based PLA is much easy to break down by earthworms than fossil-based PET. Submicron and nanocron PLA accounted for 57 and 13% of the excreted PLA on the 10th day of excretion. MP excretion was well described with the first-order kinetic model, and the elimination half-life was 9.3 (for PET) and 45 h (for PLA). A longer excretion period of PLA may be related to its potential to break down in the earthworms' digestive tract. This not only promotes the environmental degradation of PLA but also suggests the ecological risk caused by nanoparticles.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Dieta , Microplásticos , Plásticos , Poliésteres , Solo , Poluentes do Solo/análise
3.
Chemistry ; 27(58): 14508-14519, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34431146

RESUMO

Two dithienocyclopentafluorene-based small-molecule acceptors (SMAs) were developed that feature methylene-functionalized conjugated side chains, to study the effect of arylmethylene substitution and its number on structure, optoelectronic properties and device performance. Results showed that two SMAs have better absorption properties and planarity, lower bandgaps and higher LUMOs compared with the control SMA without conjugated side chains. The synthesized SMAs were tested in polymer solar cells for examples of their applicability. This work argues that the introduction of methylene-functionalized conjugated side chains has great potential in tuning molecular structure, optoelectronic properties, device physics and photovoltaic performance of SMAs.

4.
Anal Chem ; 92(20): 13930-13935, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32969220

RESUMO

The quantitative detection methods for many microplastic (MP) polymers in the environment are inadequate. For example, effective detection methods for nylon (polyamide, PA), a widely used plastic, in different environmental samples are still lacking. In the present study, a method based on acid depolymerization-liquid chromatography-tandem mass spectrometry (LC-MS/MS) and without the separation of MPs from samples was developed to quantify nylon MPs. After removing the background monomer compounds, PA6 and PA66 were efficiently depolymerized to 6-aminocaproic acid and adipic acid, respectively, and detected by LC-MS/MS. Accordingly, the quantity of nylon MPs was accurately calculated. By using the proposed method, the recovery of spiked PA6 and PA66 MPs in the environmental samples ranged from 90.8 to 98.8%. The limits of quantification for PA6 and PA66 MPs were 0.680 and 4.62 mg/kg, respectively. PA MPs were widely detected in indoor dust, sludge, marine sediment, freshwater sediment, fishery sediment, and fish guts and gills with concentrations of 0.725-321 mg/kg. Extremely high concentrations of PA66 MPs were detected in indoor dust and fish guts and gills, indicating the unequivocal risk of human exposure through dust ingestion and dietary exposure.


Assuntos
Microplásticos/análise , Nylons/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão , Monitoramento Ambiental , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção
5.
Cardiology ; 135(3): 151-159, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27344599

RESUMO

OBJECTIVES: Atrial fibrosis, a marker of atrial structural remodeling, plays a critical role in atrial fibrillation (AF). α- Actinin-2 is associated with structural remodeling related to stretching. The transforming growth factor-ß1 (TGF-ß1)/Smad pathway plays an important role in atrial fibrosis. We investigated the effects of the TGF-ß1/Smad signaling pathway on α-actinin-2 in atrial fibrosis in patients with AF. METHODS: Forty-one right atrial specimens obtained from patients with rheumatic heart disease (RHD) were divided into a chronic (c)AF group, i.e. RHD + cAF (n = 29), and a sinus rhythm group, i.e. RHD + sinus rhythm (n = 12). Patients with congenital heart disease (CHD) and sinus rhythm who underwent heart surgery served as controls (n = 10). Fibrosis was assessed by histological examination, and expression of α-actinin-2, TGF-ß1 and Smad2/phosphorylated Smad2 (p-Smad2) was evaluated by immunohistochemistry, quantitative real-time PCR and Western blotting. In rat atrial fibroblasts treated with TGF-ß1, the collagen content was measured using hydroxyproline detection, and α-actinin-2 and p-Smad2 were evaluated by semiquantitative reverse-transcription PCR and Western blotting. RESULTS: The histology results revealed a significant increase in atrial fibrosis in AF patients. The collagen content, mRNA and protein expression levels of α-actinin-2 and the components of the TGF-ß1/Smad signaling pathway were significantly gradually increased in the CHD + sinus rhythm, RHD + sinus rhythm and RHD + cAF groups (p < 0.05). The mRNA and protein levels of α-actinin-2 and TGF-ß1 in RHD patients were positively correlated with the collagen volume fraction. A positive correlation between the expression of α-actinin-2 and TGF-ß1 was also observed. In rat atrial fibroblasts treated with TGF-ß1, the collagen content was greater than that in the control group (p < 0.05), and the expression levels of α- actinin-2 and p-Smad2 were also upregulated (p < 0.05). CONCLUSIONS: α-Actinin-2 expression was increased in the atrial tissues of patients with AF secondary to RHD. α-Actinin-2 was upregulated via the TGF-ß1/Smad pathway in atrial fibroblasts, which suggests that it may be involved in TGF-ß1/Smad pathway-induced atrial fibrosis in patients with AF.


Assuntos
Actinina/metabolismo , Fibrilação Atrial/metabolismo , Átrios do Coração/metabolismo , Cardiopatia Reumática/complicações , Actinina/genética , Animais , Fibrilação Atrial/etiologia , Western Blotting , Células Cultivadas , Feminino , Fibroblastos/metabolismo , Átrios do Coração/citologia , Átrios do Coração/patologia , Humanos , Masculino , Redes e Vias Metabólicas , Microscopia Eletrônica , Pessoa de Meia-Idade , Miocárdio/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima
6.
J Oral Maxillofac Surg ; 74(5): 927.e1-927.e13, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26851314

RESUMO

PURPOSE: Temporomandibular joint osteoarthritis (TMJOA) is an important subtype of temporomandibular disorder. This study investigated the inflammatory role of the stromal cell-derived factor-1 (SDF-1) and C-X-C chemokine receptor-4 (CXCR4) axis and the probable signaling pathway involved in matrix metalloprotease (MMP)-3 and MMP-9 productions stimulated by the SDF-1-CXCR4 axis in an experimental rat model of TMJOA. MATERIALS AND METHODS: Rats were randomly divided into a control group, a pathologic model group, and an AMD3100 group. Effects of the bicyclam derivative AMD3100 (the specific antagonist of SDF-1-CXCR4 axis) were studied in TMJOA experimentally induced by monosodium iodo-acetate. Productions of SDF-1 and CXCR4 were compared in the normal and pathologic model groups, and cartilage changes and expressions of MMP-3, MMP-9, and phosphorylated extracellular signal-regulated kinase (p-ERK) were compared in the control, pathologic model, and AMD3100 groups. RESULTS: Expressions of SDF-1 and CXCR4 in the pathologic model group were increased compared with the control group (P < .05). Releases of MMP-3, MMP-9, and p-ERK and cartilage changes were downregulated in the AMD3100 group compared with the pathologic model group (P < .05), and these changes occurred in a dose-dependent manner with AMD3100 concentrations. Moreover, there were strong predictive relations between the expression of p-ERK with MMP-3 (r(2) = 0.419; P < .001) and with MMP-9 (r(2) = 0.542; P < .001). CONCLUSIONS: The SDF-1-CXCR4 signaling pathway plays a proinflammatory role in experimental TMJOA, the bicyclam derivative AMD3100 can alleviate the severity of experimental TMJOA, and there might be a potential relation between the SDF-1-CXCR4 axis and the ERK signaling pathway.


Assuntos
Compostos Heterocíclicos/uso terapêutico , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Inibidores de Metaloproteinases de Matriz/uso terapêutico , Osteoartrite/tratamento farmacológico , Transtornos da Articulação Temporomandibular/tratamento farmacológico , Animais , Benzilaminas , Cartilagem/metabolismo , Quimiocina CXCL12/fisiologia , Ciclamos , Modelos Animais de Doenças , Feminino , Ratos , Ratos Wistar , Receptores CXCR4/fisiologia , Acetato de Sódio/farmacologia
7.
Environ Sci Pollut Res Int ; 31(19): 28525-28537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38558348

RESUMO

Herein, novel catalysts of Fe-containing zeolite-A (Fe/zeolite-A) were synthesized by exchanging iron ions into zeolite-A framework, and short-chain organic acids (SCOAs) were employed as chelating agents. Reactive Brilliant Blue KN-R (KN-R) was used as a model pollutant to evaluate the performance of these catalysts based on the heterogeneous Fenton reaction. The results showed that Fe-OA/3A, which applied zeolite-3A as the supporter and oxalic as the chelating agent, presented the most prominent KN-R decolorization efficiency. Under the initial pH of 2.5, 0.4 mM KN-R could be totally decolorized within 20 min. However, the mineralization efficiency of KN-R was only 58.2%. Therefore, anthraquinone dyes were introduced to modify zeolite-3A. As a result, the mineralization efficiency of KN-R was elevated to 92.7% when using Alizarin Violet (AV) as the modifier. Moreover, the modified catalysts exhibited excellent stability, the KN-R decolorization efficiency could be maintained above 95.0% within 20 min after operating for nine cycles. The mechanism revealed that the Fe(II)/Fe(III) cycle was accelerated by AV-modified catalyst thus prompting the KN-R decolorization in Fenton-like system. These findings provide new insights for preparing catalysts with excellent activity and stability for dye wastewater treatment.


Assuntos
Ferro , Zeolitas , Zeolitas/química , Ferro/química , Corantes/química , Poluentes Químicos da Água/química , Catálise , Antraquinonas/química , Benzenossulfonatos/química , Peróxido de Hidrogênio/química
8.
J Sep Sci ; 36(2): 414-20, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23255332

RESUMO

An ionic liquid (IL) based dispersive liquid-liquid microextraction combined with HPLC hydride generation atomic fluorescence spectrometry method for the preconcentration and determination of mercury species in environmental water samples is described. Four mercury species (MeHg(+), EtHg(+), PhHg(+), and Hg(2+)) were complexed with dithionate and the neutral chelates were extracted into IL drops using dispersive liquid-liquid microextraction. Variables affecting the formation and extraction of mercury dithizonates were optimized. The optimum conditions found were as follows: IL-type and amount, 0.05 g of 1-octyl-3-methylimidazolium hexafluorophosphate; dispersive solvents type and amount, 500 µL of acetone; pH, 6; extraction time, 2 min; centrifugation time, 12 min; and no sodium chloride addition. Under the optimized conditions, the detection limits of the analytes were 0.031 µg/L for Hg(2+), 0.016 µg/L for MeHg(+), 0.024 µg/L for EtHg(+), and 0.092 µg/L for PhHg(+), respectively. The repeatability of the method, expressed as RSD, was between 1.4 and 5.2% (n = 10), and the average recoveries for spiked test were 96.9% for Hg(2+), 90.9% for MeHg(+), 90.5% for EtHg(+), 92.3% for PhHg(+), respectively. The developed method was successfully applied for the speciation of mercury in environmental water samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Compostos de Mercúrio/análise , Compostos de Mercúrio/isolamento & purificação , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Líquidos Iônicos/química
9.
Chemosphere ; 327: 138516, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36972874

RESUMO

An amorphous porous iron material (FH) was firstly self-synthesized using a simple coprecipitation approach and then utilized to activate peroxymonosulfate (PMS) for the catalytic degradation of pyrene and remediation of PAHs contaminated soil on site. FH exhibited more excellent catalytic activity than traditional hydroxy ferric oxide and possessed stability at a pH range of 3.0-11.0. According to quenching studies and electron paramagnetic resonance (EPR) analyses, non-radicals (Fe(IV) = O and 1O2) were the major reactive oxygen species (ROS) in the FH/PMS system's degradation of pyrene. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) of FH before and after the catalytic reaction, as well as active site substitution experiments and electrochemical analysis all verified that PMS adsorbed on FH could produce more abundant bonded hydroxyl groups (Fe-OH) which dominated the radical and non-radical oxidation reactions. Then, a possible pathway for pyrene degradation was presented according to gas chromatography-mass spectrometry (GC-MS). Furthermore, the FH/PMS system exhibited excellent catalytic degradation in the remediation of PAH-contaminated soil at real sites. This work provides a remarkable potential remediation technology of persistent organic pollutants (POPs) in environmental and will contribute to understanding the mechanism of Fe-based hydroxides in advanced oxidation processes.


Assuntos
Ferro , Peróxidos , Ferro/química , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Peróxidos/química , Pirenos
10.
Chemosphere ; 325: 138409, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36925015

RESUMO

The application of sludge biochar (SC) materials as efficient catalysts for organic pollutants mineralization via advanced oxidation process meets the good strategy of "make waste profitable". The catalytic oxidations of methyl orange (MO) and pyrene by oxalic acid modified sludge biochar (SC-OA) with and without H2O2 were carried out. The analysis of Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), electronic paramagnetic resonance spectrometer (EPR) and free radical quenching experiment were performed and the definite relationships between persistent free radicals (PFRs) type and specific reactive oxygen species (ROS) were made clear. It is suggested for the first time that carbon-centered type PFRs in SC-OA without H2O2 could form O2•- and •OH from COOH groups, while oxygen-centered type PFRs induced H2O2 to produce •OH. The degradation intermediates of MO and pyrene were identified and the transformation pathways were proposed. SC-OA, possessing good sustainable utilization and clean catalytic property, is expected to be popularized and applied in the mineralization of organic pollutants, especially in the in-situ remediation of contaminated soil where is no continuous supply of H2O2.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Esgotos , Ácido Oxálico , Poluentes Ambientais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Peróxido de Hidrogênio , Carvão Vegetal/química , Radicais Livres , Poluentes Químicos da Água/análise
11.
Chemosphere ; 333: 138869, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37156290

RESUMO

Arsenic pollution in environment has always been an important environmental problem that has attracted wide attention in recent years. Adsorption is one of the main methods of treatment for arsenic in the aqueous solution and soil because of the advantages of high efficiency, low cost and wide application. Firstly, this report summarizes the commonly and widely used adsorbent materials such as metal-organic frameworks, layered bimetallic hydroxides, chitosan, biochar and their derivatives. The adsorption effects and mechanisms of these materials are further discussed, and the application prospects of these adsorbents are considered. Meanwhile, the gaps and deficiencies in the study of adsorption mechanism was pointed out. Then, this study comprehensively evaluated the effects of various factors on arsenic transport, including (i) the effects of pH and redox potential on the existing form of As; (ii) complexation mechanism of dissolved organic matter and As; (iii) factors affecting the plant enrichment of As. Finally, the latest scientific researches on microbial remediation of arsenic and the mechanisms were summarized. The review finally enlightens the subsequent development of more efficient and practical adsorption material.


Assuntos
Arsênio , Poluentes do Solo , Arsênio/análise , Solo , Carvão Vegetal , Água , Poluição Ambiental , Poluentes do Solo/análise , Adsorção
12.
J Hazard Mater ; 458: 131979, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37423136

RESUMO

In the study, we investigated the different compositions of biochar-derived dissolved organic matter (BDOM) that play a key role in the biodegradation of sulfamethoxazole (SMX) and chloramphenicol (CAP) by P. stutzeri and S. putrefaciens, and found that aliphatic compounds in Group 4, fulvic acid like in Region III, and solid microbial byproduct like in region IV are key common factors. The growth and antibiotic degradation efficiency of P. stutzeri and S. putrefaciens are positively correlated with the content of Group 4 and Region III, and negatively correlated with Region IV. This is consistent with the optimal biodegradation results of BDOM700 with the highest content of Group 4 and Region III. Additionally, the degradation efficiency of SMX by Pseudomonas stutzeri is negatively correlated with the percentage of polycyclic aromatics in Group 1, but not with CAP. Similarly, the percentage of fatty acids in S. putrefaciens was positively correlated with Group 1, whereas P. stutzeri did not. This indicates that some components of BDOM have varying effects on different bacteria or types of antibiotics. This study provides new insights into enhancing antibiotic biodegradation by controlling the composition of BDOM.


Assuntos
Cloranfenicol , Sulfametoxazol , Sulfametoxazol/metabolismo , Biodegradação Ambiental , Antibacterianos
13.
Chemosphere ; 313: 137450, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36464017

RESUMO

The remediation for industrial site soil has attracted public concerns because of the hazardous and hydrophobic properties of organic pollutants existed in the soil. The persulfate oxidation activated by Fe2+ chelated with sodium citrate (PS/Fe2+/SC) was used to remediate different types of industrial site soils in the present study. The maximum removal rates of Σ16 PAHs in the Nanjing site soil (NJS) and Hefei site soil (HFS) were 73.6% and 85.8% after the second-stage oxidation, respectively. The late oxidation stages couldn't enhance the degradation efficiency of PAHs due to the increase of high crystalline Fe mineral phases both in the NJS and HFS, which significantly decreased the Fe2+/Fe3+ recycle and further inhibited the reactive oxygen species production during the remediation. The remediation using PS/Fe2+/SC could change the soil physicochemical properties, such as the functional groups, specific surface area (SSA), total pore volume (TPV) and some UV spectral parameters of soil particles. Additionally, the oxidation of PS/Fe2+/SC also altered the composition of soil dissolve organic matters, especially the fulvic acid, which further affected the Fe2+ oxidation. The study mainly discloses the mechanism of limitation using persulfate oxidation activated by Fe materials at late oxidation stage.


Assuntos
Recuperação e Remediação Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Oxirredução , Hidrocarbonetos Policíclicos Aromáticos/análise , Citrato de Sódio , Solo/química , Poluentes do Solo/análise , Sulfatos/química , Ferro/química , Quelantes/química
14.
Front Physiol ; 14: 1181510, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637145

RESUMO

Introduction: Coronary artery disease (CAD) is one of the most life-threatening cardiovascular emergencies with high mortality and morbidity. Increasing evidence has demonstrated that the degree of hypoxia is closely associated with the development and survival outcomes of CAD patients. However, the role of hypoxia in CAD has not been elucidated. Methods: Based on the GSE113079 microarray dataset and the hypoxia-associated gene collection, differential analysis, machine learning, and validation of the screened hub genes were carried out. Results: In this study, 54 differentially expressed hypoxia-related genes (DE-HRGs), and then 4 hub signature genes (ADM, PPFIA4, FAM162A, and TPBG) were identified based on microarray datasets GSE113079 which including of 93 CAD patients and 48 healthy controls and hypoxia-related gene set. Then, 4 hub genes were also validated in other three CAD related microarray datasets. Through GO and KEGG pathway enrichment analyses, we found three upregulated hub genes (ADM, PPFIA4, TPBG) were strongly correlated with differentially expressed metabolic genes and all the 4 hub genes were mainly enriched in many immune-related biological processes and pathways in CAD. Additionally, 10 immune cell types were found significantly different between the CAD and control groups, especially CD8 T cells, which were apparently essential in cardiovascular disease by immune cell infiltration analysis. Furthermore, we compared the expression of 4 hub genes in 15 cell subtypes in CAD coronary lesions and found that ADM, FAM162A and TPBG were all expressed at higher levels in endothelial cells by single-cell sequencing analysis. Discussion: The study identified four hypoxia genes associated with coronary heart disease. The findings provide more insights into the hypoxia landscape and, potentially, the therapeutic targets of CAD.

15.
Oncol Res ; 31(4): 569-590, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415742

RESUMO

Hepatocellular carcinoma (HCC) is the most common fatal cancer worldwide, patients with HCC have a high mortality rate and poor prognosis. PANoptosis is a novel discovery of programmed cell death associated with cancer development. However, the role of PANoptosis in HCC remains obscure. In this study, we enrolled 274 PANoptosis-related genes (PANRGs) and screened 8 genes to set up a prognostic model. A previous scoring system calculated PANscore was utilized to quantify the individual risk level of each HCC patient, and the reliability of the prognostic model has been validated in an external cohort. Nomogram constructed with PANscore and clinical characteristics were used to optimize individualized treatment for each patient. Single-cell analysis revealed a PANoptosis model associated with tumor immune cell infiltration, particularly natural killer (NK) cells. Further exploration of hub genes and assessment of the prognostic role of these 4 hub genes in HCC by quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC). In conclusion, we evaluated a PANoptosis-based prognostic model as a potential prognostic biomarker for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Reprodutibilidade dos Testes , Microambiente Tumoral/genética , Neoplasias Hepáticas/genética , Apoptose , Prognóstico
16.
J Hazard Mater ; 453: 131450, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37088021

RESUMO

The remediation of soil contaminated with hydrophobic organic pollutants has attracted great public concern. In the present study, a novel catalyst using biochar supported ferro ferric oxide modified by carboxymethyl cellulose (CMC-Fe3O4/BC) was developed to activate the Fenton reaction for hazardous hydrophobic organic pollutants, and the degradation mechanisms were analyzed in terms of free radicals, electron transfer pathways and degradation intermediates. The results showed that the CMC-Fe3O4/BC-activated H2O2 system degraded nearly 100% of pyrene in the aqueous system after a 1440-min reaction. The catalyst was also applied to remediate industrial field soil contaminated with PAHs and γ-HCH. The removal rate of the total pollutants reached 61.1% after a 10-day reaction, which was higher than that of Fe3O4/BC without modification. CMC enabled the Fe3O4 particles to more equably distribute on the BC surface, further effectively activating H2O2 to generate more ⋅OH and forming different degradation products compared to the Fe3O4/BC. Additionally, the CMC-Fe3O4/BC-activated H2O2 system obviously enhanced electron transfer on the BC surface. Thus, the PAHs and γ-HCH could be degraded via electron transfer pathways.

17.
J Hazard Mater ; 426: 128083, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34923382

RESUMO

A novel eco-friendly material (CS-U@PS) for persulfate slow-release to effectively degrade organic pollutants (methyl orange and pyrene) was synthesized using chitosan and urea as the encapsulated framework materials via an emulsion cross-linking method for the first time. The obtained CS-U@PS exhibits spherical shapes with a uniform size of approximately 2-3 µm according to the particle-size distribution and SEM image results. The slow-release mechanism was proposed through a kinetics model study and the Ritger-Peppas model fit well (r2 = 0.9699) to indicate that the slow-release process is non-Fickian diffusion. The influences of urea and PS dosages and oxidative conditions on methyl orange degradation were studied, and all the results suggested that urea played an important role in PS slow-release and can also catalyze the activation of PS by iron to further produce radicals and improve the removal efficiency of pollutants. A pyrene removal rate of 90.53% was achieved in aqueous solutions and an above 80% removal rate was obtained in weakly acidic or neutral soil environments by CS-U@PS activated by Fe2+ with citric acid as the chelating agent. Therefore, the fabricated slow-release oxidation materials exhibit application potential for the remediation of organic polluted groundwater and soil.


Assuntos
Quitosana , Poluentes Ambientais , Poluentes Químicos da Água , Oxirredução , Sulfatos , Ureia , Poluentes Químicos da Água/análise
18.
Environ Sci Pollut Res Int ; 29(55): 83234-83246, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35764728

RESUMO

Once the sludge was directly used in the farmland, it will have a negative impact on human health through the food chain because sludge contains pollutants. Sewage sludge pyrolysis into biochar is an effective way to realize sludge harmless and resourceful utilization. This research used hydrothermal carbonization method to convert sludge into sludge biochar (SLBC) to reduce the types and contents of pharmaceuticals and personal care products (PPCPs) and available heavy metals. Furthermore, migration of the residual caffeine (Caf), acetaminophen (Ace), and heavy metals (Cr, Pb, Cu, Zn) released from the SLBC in the wheat was assessed. The results showed that the levels of Caf, Ace, Pb, Cu, and Zn accumulated in the shoots were lower than the limit regulated by Drug and Food Additive Use Standard in China (Caf: 150 mg/kg; Ace: 2.5 ~ 5 mg/kg; Pb: 0.3 mg/kg; Cu: 10 mg/kg; Zn: 20 mg/kg). The migration of Cr from roots to shoots was also significantly controlled by SBLC. SBLC delayed the germination time of wheat seeds with increasing in hydrothermal temperature, the germination rate and root length showed a decreasing trend. Evans blue and O2- fluorescence staining of root tips also confirmed this conclusion. When the wheat was exposed to the low temperature and dose of SLBC, the chlorophyll contents and growth of wheat can be significantly increased; the oxidative damage of cell plasma membrane and net photosynthetic rate were reduced. However, 0.8 g/L of SLBC made plants suffer abiotic stress and caused oxidative damage to plants, and decreased membrane system stability. The study provides some parameters for sludge to realize resource utilization in the agricultural system.


Assuntos
Metais Pesados , Esgotos , Humanos , Triticum/metabolismo , Chumbo , Solo , Metais Pesados/análise
19.
J Sep Sci ; 34(18): 2371-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21793210

RESUMO

A simple, sensitive and accurate reversed-phase high-performance liquid chromatographic (HPLC) method for simultaneous determination of three naturally occurring estrogenic steroids including estrone (E1), 17ß-estradiol (E2) and estriol (E3) in environmental water samples was developed. Analytes were extracted with ethyl acetate solvents and preconcentrated prior to HPLC analysis. Separations were accomplished in <20 min using a reversed-phase C(18) column (4.6×250 mm id, 5 µm) with a gradient elution of mobile phase containing 3.0 mM ammonium acetate/acetonitrile mixtures (flow rate, 1.0 mL/min). UV light absorption responses at 205 nm were linear over a wide concentration range from 100,000 µg/L to the detection limits of 0.96 µg/L E1, 0.64 µg/L E2 and 0.78 µg/L E3. Quantitation was carried out by the peak area method. The relative standard deviation for the analysis of three estrogens was <3.0%. This method was applied for the simultaneous determination of estrogens in environmental water samples collected in Zhejiang, China. The higher concentrations of both E2 and E3 were found in Tang River and West Lake waters, and E1 was detected in lake water only. All three estrogens were below the detection limits in rain waters.


Assuntos
Estradiol/análise , Estriol/análise , Estrona/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Cromatografia Líquida de Alta Pressão , Conformação Molecular , Estereoisomerismo
20.
Environ Technol ; 42(28): 4426-4433, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32324105

RESUMO

The mixed-metal oxide Ni/Fe3O4/TiO2 with two metal-oxide interfaces to catalyze sequential chemical reactions was first applied in the decomposition of phosphine gas for yellow phosphorus (P4) production. The catalyst was prepared with tunable Ni-Fe3O4 and Ni-TiO2 interactions via annealing and subsequent reduction. Ni/Fe3O4/TiO2 exhibited significantly effective activity and good stability in the PH3 decomposition, which were achieved by modulating the metal-support interaction. The characterizations by scanning electron microscopy(SEM), X-ray diffraction analysis(XRD), BET surface area measurement and X-ray photoelectron spectroscopy(XPS) were carried out. The enhancements of the Ni-Fe3O4 and Ni-TiO2 dual interactions by annealing and reduction were verified and the mechanism of PH3 decomposition over the modulated Ni/Fe3O4/TiO2 catalyst was investigated. NiOOH as an active catalytic intermediate species is produced by the synergistic catalytical dual interfaces. The catalytic reaction pathways of PH3 decomposition by the dual interfaces were firstly revealed. The results provide underlying insights in the way to promote the catalytic performance for synergistic catalysis in PH3 decomposition.


Assuntos
Óxidos , Titânio , Catálise
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