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1.
Ecotoxicol Environ Saf ; 214: 112115, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33691242

RESUMO

Nanoplastics (NPs) are becoming an emerging pollutant of global concern. A potential risk of NPs is that they can serve as carriers and synergistically function with other contaminants to cause diseases. A variety of diseases such as Alzheimer's disease are related to the generation of amyloid fibrils, and insulin is typically used as a model to study the fibrillation process. In this study, we examined the fibrillation of insulin promoted by polystyrene nanoplastics (PSNPs) alone and synergistically with organic contaminants (denoted as X, X = pyrene, bisphenol A, 2,2',4,4'-tetrabromodiphenyl ether, 4,4'-dihydroxydiphenylmethane, or 4-nonylphenol) having different polarities using thioflavin T fluorescence assays, dynamic light scattering, and circular dichroism spectroscopy. The presence of PSNPs and small organic contaminants decreased the lag phase time (tlag) for insulin fibrillation from 54.6 h to 35-51 h and their combination (PS-X) enhanced this process (tlag = 21-30 h). Notably, the lag phase time for insulin fibrillation with PS-nonpolar contaminants, PS-weakly polar contaminants, and PS-polar contaminants is around 20.8, 26.7, and 30.1 h, respectively, indicating the synergistic effect of PS-nonpolar contaminants or PS-weakly polar contaminants was more obvious than that of PS-polar contaminants. Moreover, molecular dynamic simulation reveal the interactions between insulin and PSs or small organic contaminants are primarily driven by van der Waals forces and hydrophobic interactions. Overall, the findings of this study underscore the potentially significant environmental impact of small organic contaminants assisting NPs in promoting insulin fibrillation.


Assuntos
Poluentes Ambientais/química , Insulina/química , Microplásticos/química , Nanopartículas/química , Poliestirenos/química , Compostos Benzidrílicos/química , Éteres Difenil Halogenados/química , Fenóis/química , Pirenos/química
2.
J Chromatogr A ; 1642: 462027, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33714772

RESUMO

Phytotoxins are plant secondary metabolites. They have recently been considered as chemicals of emerging concern (CECs) and there is a growing interest in their environmental fate and potential threat to public health. Dedicated target and non-target screening (NTS) analysis of phytotoxins in environmental samples are sparse, meanwhile phytotoxins are rarely detected in NTS-based analysis due to lack of an efficient methodology. Development of new analytical measurement methods is therefore highly needed. In this study, we for the first time investigated key parameters of reversed phase liquid chromatography-high resolution mass spectrometry (RPLC-HRMS) for five major classes of phytotoxins (alkaloids, steroids, terpenoids, flavonoids and aromatic polyketides) in environmental matrices; the investigation included analytical conditions which have not yet been explored by others, e.g. ionization at alkaline pH above 9. As the outcome we established a new analytical method for target/suspect screening and NTS of phytotoxins in the environment, which significantly improved the detection sensitivity with up to 40 times compared to previous methods, and enabled the discovery of over 30 phytotoxins in a NTS-based environmental study. We also observed that the negative ionization of phenols could be facilitated by the number of hydroxyl groups on the ring rather than their position of substitution. This study is of interest for a better fundamental understanding of the behavior of phytotoxins in LC-MS. Dedicated target/suspect screening and NTS methods will facilitate a better risk characterization of phytotoxins in the environment and stimulate implementation of new public regulation on phytotoxins.


Assuntos
Poluentes Ambientais/química , Espectrometria de Massas/métodos , Toxinas Biológicas/química , Cromatografia Líquida , Cromatografia de Fase Reversa , Concentração de Íons de Hidrogênio , Lupinus/química , Fenóis/análise , Padrões de Referência , Solo/química , Espectrometria de Massas por Ionização por Electrospray , Temperatura , Fatores de Tempo , Toxinas Biológicas/análise , Água/química
3.
J Chromatogr A ; 1643: 462042, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33761434

RESUMO

This review specifically examines the development of sample preparation methods for residue analyses of neonicotinoid insecticides in agricultural and environmental matrices. Pesticide residue analysis is fundamentally important to ensure the safety of foods and processed foods of plant and animal origin, and to preserve the environment, particularly soil and water. For the development of pesticide residue analysis, the sample preparation process is an important key to maximizing the analytical performance of highly sensitive and accurate chromatographic instruments and to acquiring reliable analytical results. This review outlines sample preparation methods that have been proposed to date for extraction of neonicotinoids that might remain in a complicated sample matrix in quantitatively trace amounts, and for cleaning up, to the greatest extent possible, the interfering components that coexist in the sample extract.


Assuntos
Agricultura , Métodos Analíticos de Preparação de Amostras , Cromatografia/métodos , Poluentes Ambientais/análise , Neonicotinoides/análise , Animais , Poluentes Ambientais/química , Neonicotinoides/química , Resíduos de Praguicidas/análise
4.
Food Chem ; 350: 129214, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33601093

RESUMO

Tetrabromobisphenol A (TBBPA), halogenated carbazole (HCZ), and their analogs are the emerging pollutants invading the marine environment. So far, a few methods have been reported for the simultaneous analysis of these pollutants due to their large polarity difference. In this study, an effective extraction and cleanup strategy was developed for the simultaneous determination of 19 TBBPA and HCZ congeners in seafood. The 19 analytes could be directly analyzed through high performance liquid chromatography after ultrasonic extraction (methanol, duplicate ethyl acetate-acetone (1:1, v/v)) and gel permeation chromatography cleanup. The acceptable spike-recoveries were within 65.7-118.3%; the precision was intra-/inter-day RSDs: 0.0-6.7%/0.0-8.5%; and the matrix effects were between -14.1% and 12.4%. The detection limits and quantification limits were 0.002-0.014 and 0.020-0.200 µg g-1 dw, respectively. Additionally, this method successfully analyzed the seafood samples and the concentrations of these analytes were in range of nd-5.4 µg g-1 dw.


Assuntos
Carbazóis/análise , Fracionamento Químico/métodos , Análise de Alimentos/métodos , Halogenação , Bifenil Polibromatos/análise , Bifenil Polibromatos/isolamento & purificação , Alimentos Marinhos/análise , Carbazóis/química , Poluentes Ambientais/análise , Poluentes Ambientais/química , Contaminação de Alimentos , Fatores de Tempo
5.
Molecules ; 26(3)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525602

RESUMO

Persistent Organic Pollutants (POPs) are a serious food safety concern due to their persistence and toxic effects. To promote food safety and protect human health, it is important to understand the sources of POPs and how to minimize human exposure to these contaminants. The POPs Program within the U.S. Food and Drug Administration (FDA), manually evaluates congener patterns of POPs-contaminated samples and sometimes compares the finding to other previously analyzed samples with similar patterns. This manual comparison is time consuming and solely depends on human expertise. To improve the efficiency of this evaluation, we developed software to assist in identifying potential sources of POPs contamination by detecting similarities between the congener patterns of a contaminated sample and potential environmental source samples. Similarity scores were computed and used to rank potential source samples. The software has been tested on a diverse set of incurred samples by comparing results from the software with those from human experts. We demonstrated that the software provides results consistent with human expert observation. This software also provided the advantage of reliably evaluating an increased sample lot which increased overall efficiency.


Assuntos
Ração Animal/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Inocuidade dos Alimentos/métodos , /química , Animais , Humanos , Software
6.
Anal Chem ; 93(4): 2299-2308, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33411532

RESUMO

ß-Lactam antibiotics such as penicillins and cephalosporins are extensively used for human infection therapy. Consistent unintended exposure to these antibiotics via food and water is known to promote antibiotic-resistant bacterial pathogenesis with high morbidity and mortality in humans. An optical enzymatic biosensor for rapid and point-of-use detection of these antibiotics in food and water has been developed and tested. Enzymatic hydrolysis of ß-lactams, on the electroactive polyaniline nanofibers, altered the polymeric backbone of the nanofibers, from emeraldine base form to emeraldine salt, which was measured as an increase in evanescent wave absorbance at 435 nm. The sensors were calibrated by spiking antibiotic-free milk with ceftazidime (as a model ß-lactam analyte) in a linear range of 0.36-3600 nM (R2 = 0.98). The calibration was further validated for packaged milk, local cow milk, and buffalo milk. A similar calibration was devised for chicken meat samples in a linear range of 9-1800 nM (R2 = 0.982) and tap water in a linear range of 0.18-180 nM (R2 = 0.99). Interestingly, it was possible to use the same calibration for the determination of other ß-lactam antibiotics (ampicillin, amoxicillin, and cefotaxime), which reflects the usefulness of the sensor for wide-scale deployment. The sensor performance was validated with a wastewater sample, from a wastewater treatment plant (WWTP), qualitatively analyzed by high-resolution liquid chromatography coupled with mass spectroscopy for detection of ß-lactams. The sensor scheme developed and tested is of grassroot relevance as a quick solution for measurement of ß-lactam residues in food and environment.


Assuntos
Compostos de Anilina/química , Antibacterianos/química , Resíduos de Drogas/química , Contaminação de Alimentos , beta-Lactamas/química , Animais , Galinhas , Monitoramento Ambiental/métodos , Poluentes Ambientais/química , Hidrólise , Carne/análise , Leite/química , Estrutura Molecular , Nanoestruturas , Fibras Ópticas , Águas Residuárias/química
7.
Int J Mol Sci ; 22(3)2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33498193

RESUMO

Due to their unique chemical properties, per- and polyfluoroalkyl substances (PFAS) have been used extensively as industrial surfactants and processing aids. While several types of PFAS have been voluntarily phased out by their manufacturers, these chemicals continue to be of ecological and public health concern due to their persistence in the environment and their presence in living organisms. Moreover, while the compounds referred to as "legacy" PFAS remain in the environment, alternative compounds have emerged as replacements for their legacy predecessors and are now detected in numerous matrices. In this review, we discuss the historical uses of PFAS, recent advances in analytical techniques for analysis of these compounds, and the fate of PFAS in the environment. In addition, we evaluate current biomonitoring studies of human exposure to legacy and emerging PFAS and examine the associations of PFAS exposure with human health impacts, including cancer- and non-cancer-related outcomes. Special focus is given to short-chain perfluoroalkyl acids (PFAAs) and ether-substituted, polyfluoroalkyl alternatives including hexafluoropropylene oxide dimer acid (HFPO-DA; tradename GenX), 4,8-dioxa-3H-perfluorononanoic acid (DONA), and 6:2 chlorinated polyfluoroethersulfonic acid (6:2 Cl-PFESA; tradename F-53B).


Assuntos
Carcinógenos Ambientais/toxicidade , Monitoramento Ambiental/métodos , Poluentes Ambientais/toxicidade , Fluorcarbonetos/toxicidade , Animais , Biodegradação Ambiental , Carcinógenos Ambientais/química , Poluentes Ambientais/química , Fluorcarbonetos/química , Humanos
9.
Ecotoxicol Environ Saf ; 208: 111689, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396021

RESUMO

Gunshot residue (GSR) stemming from the discharge of firearms has been essential to advancements in the field of forensic science however the human and environmental health impacts from GSR are far less researched. GSR represents a multifaceted concern: it contains a complex mixture of inorganic and organic components and produces airborne particles with variable sizes, depositions, and fates. Herein we evaluate studies in the literature examining GSR collection, deposition, composition, environmental contamination, and potential remediation techniques within the last two decades (2000 - 2020). Throughout we reflect upon key findings and weaknesses in relation to environmental characterization of GSR and associated firearm contaminants. Research focused on techniques to analyze both inorganic and organic GSR simultaneously has begun, but requires additional effort. A vast majority of the available environmental characterization literature focuses on soil contamination at outdoor firing ranges for a select number of elements (Cu, Pb, Sb) with comparisons between ranges or at different collection distances and depths. There is limited ability for between study comparisons due to collection and analysis differences as well as a lack of background soil sampling. Notably, these studies lack direct quantification of the contribution of contaminants from GSR as well as analysis of organic compounds. Currently, there is a need for air monitoring to determine the composition, deposition, and fate of GSR, particularly in outdoor settings. This review summarizes the collection, characterization, and environmental studies related to GSR and highlights areas of research needed to establish the environmental health impacts.


Assuntos
Poluentes Ambientais , Poluição Ambiental/análise , Recuperação e Remediação Ambiental/métodos , Armas de Fogo , Animais , Antimônio/análise , Poluentes Ambientais/análise , Poluentes Ambientais/química , Poluição Ambiental/prevenção & controle , Humanos , Chumbo/análise , Compostos Orgânicos/análise
10.
Ecotoxicol Environ Saf ; 208: 111635, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396155

RESUMO

Micellar enhanced ultra-filtration (MEUF) is a modified ultrafiltration (UF) method that can remove small molecules that are not effectively removed by UF alone. In this work we used a similar semi-equilibrium dialysis (SED) method to characterize two anionic surfactants, sodium dodecyl sulfate (SDS) and sodium laurate (SOL), as MEUF candidates to remove several polycyclic aromatic hydrocarbon (PAH) compounds. These anionic surfactants have low toxicity and are more biodegradable compared to the fairly toxic and persistent cetyltrimethylammonium bromide (CTABr) and similar cationic surfactants, which is important as MEUF surfactants may be present in the treated effluent. The log binding constants (Log KB) of the PAHs naphthalene, phenanthrene, pyrene and fluorene to SDS ranged from 3.07 to 4.48, which compared well with the previous results for CTABr and indicated that SDS is an excellent candidate for MEUF. The log binding constants for the same PAHs with SOL micelles ranged from 2.11 to 3.53, which suggested that SOL might be adequate for stronger-binding PAH like pyrene and fluorene but less suitable for naphthalene and phenanthrene. The results demonstrated a strong correlation between the Log KB with one micelle type and the Log KB with the other, suggesting a common set of properties and interactions are responsible for the binding. Similar to the previous results for CTABr, a significant correlation between Log KB and Log KOW values indicates that hydrophobic character is the main driving force for PAH binding with these anionic micelles. This may also be useful for predicting MEUF performance for various compound/surfactant combinations where Log KB is not known.


Assuntos
Ácidos Láuricos/química , Micelas , Hidrocarbonetos Policíclicos Aromáticos/química , Dodecilsulfato de Sódio/química , Tensoativos/química , Cetrimônio/química , Poluentes Ambientais/química , Interações Hidrofóbicas e Hidrofílicas , Ultrafiltração/métodos
11.
Ecotoxicol Environ Saf ; 208: 111697, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396028

RESUMO

Owing to the unique properties and useful applications in numerous fields, nanomaterials (NMs) received a great attention. The mass production of NMs has raised major concern for the environment. Recently, some altered growth patterns in plants have been reported due to the plant-NMs interactions. However, for NMs safe applications in agriculture and medicine, a comprehensive understanding of bio-nano interactions is crucial. The main goal of this review article is to summarize the results of the toxicological studies that have shown the in vitro and in vivo interactions of NMs with plants. The toxicity mechanisms are briefly discussed in plants as the defense mechanism works to overcome the stress caused by NMs implications. Indeed, the impact of NMs on plants varies significantly with many factors including physicochemical properties of NMs, culture media, and plant species. To investigate the impacts, dose metrics is an important analysis for assaying toxicity and is discussed in the present article to broadly open up different aspects of nanotoxicological investigations. To access reliable quantification and measurement in laboratories, standardized methodologies are crucial for precise dose delivery of NMs to plants during exposure. Altogether, the information is significant to researchers to describe restrictions and future perspectives.


Assuntos
Ecotoxicologia/normas , Poluentes Ambientais/toxicidade , Nanoestruturas/toxicidade , Plantas/efeitos dos fármacos , Agricultura , Ecotoxicologia/tendências , Poluentes Ambientais/química , Humanos , Nanoestruturas/química , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas/classificação , Plantas/metabolismo , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos
12.
Ecotoxicol Environ Saf ; 211: 111934, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33472109

RESUMO

In the present work, we reported a one pot simple colloidal-gel synthesis of molybdenum bismuth vanadate (MoBiVO4). The charge transfer property of MoBiVO4 was improved by developing a composite with graphene oxide (GO) through sonochemical technique. The optical and morphological analysis revealed that successful formation of GO-MoBiVO4 composite without any other filth. As prepared composite was used to modify the superficial surface of glassy carbon electrode (GO-MoBiVO4/GCE) and applied for the selective detection of environmental pollutant 2, 4, 6 trichrlorophenol (TCP). The electron channeling capability of GO with molybdenum bismuth vanadate possessed a superior electrochemical response in cyclic voltammetry (CV), whereas bare GCE and other modified electrodes provided an inferior response with lower current response. The differential pulse voltammetry (DPV) response of TCP at GO-MoBiVO4/GCE outcomes with low level detection of 0.4 nM and higher sensitivity of 2.49 µA µM-1 cm-2 with wider linear response 0.199-17.83 µM. Furthermore, the proposed sensor applied in practicability analysis and the results indicates GO-MoBiVO4/GCE prominent towards electrochemical detection of TCP.


Assuntos
Bismuto/química , Clorofenóis/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Grafite/química , Molibdênio/química , Vanadatos/química , Carbono/química , Clorofenóis/química , Técnicas Eletroquímicas/métodos , Eletrodos , Poluentes Ambientais/química
13.
Ecotoxicol Environ Saf ; 211: 111940, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33476849

RESUMO

Desorption is one of the main factors causing groundwater and soil pollution. Therefore, the study of clay desorption characteristics is important for the prediction of groundwater and soil pollution. In previous studies, batch tests and column tests were used to study the desorption characteristics of pollutants on clay. However, the desorption parameters obtained via the two test methods were often quite different. To investigate differences in the desorption characteristics of different pollutants on clay particles and in compacted clay, batch and column desorption tests were conducted using cadmium chloride, fulvic acid, and sodium phosphate as the adsorbates and bentonite as the adsorbent. It was found that the unit particle surface area desorption distribution coefficients of pollutants on bentonite particles were approximately equal to the unit pore surface area distribution coefficients of pollutants in compacted bentonite. This indicates that the desorbed amount per unit of surface area is basically consistent, regardless of whether they are sorbed on particles or in compacted bentonite. A simple formula for determining the desorption retardation factor of pollutants in compacted bentonite is presented. The results of this study provide a reference for the prediction and evaluation of groundwater and soil pollution.


Assuntos
Bentonita/química , Poluentes Ambientais/química , Adsorção , Argila , Água Subterrânea , Modelos Químicos , Fosfatos
14.
Int J Biol Macromol ; 169: 436-442, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33309668

RESUMO

Recently, photo-degradation process under ultraviolet-light irradiation is being used as a substantial treatment method for the removal of environmental pollution. In this study, a silver phosphate-ilmenite (Ag3PO4-FeTiO3) hetero structure supported on glycol chitosan catalyst was completely prepared, also, and its structural, and optical properties were characterized. Meantime, scanning electron microscopy, X-ray diffraction, X-ray photoelectron, and UV-vis spectra were applied. The Ag3PO4-FeTiO3/glycol chitosan catalyst was used to degrade metronidazole under visible-light irradiation. The degradation rate of metronidazole in 25 min by Ag3PO4-FeTiO3/glycol chitosan nanocomposites was found to be 99.2% under UV light irradiation, which was higher than that by Ag3PO4-FeTiO3 (72.24%) and FeTiO3 (35.5%), respectively. The active species trapping test of Ag3PO4-FeTiO3/glycol chitosan indicated that ·OH and ·O2- participated during the reaction. The diffusion method was evaluated to appraise the bactericidal activity of the synthesized nanomaterials when tested against both Staphylococcus aureus and Escherichia coli bacteria, with or without LED-light irradiation. The antibacterial tests show higher inhibition zones under light illumination as compared to dark conditions. The antifungal properties of the prepared nanomaterials were analyzed by fungi (Aspergillus niger, and Fusarium solani) using disc diffusion analysis. It was confirmed that the prepared nanomaterials have the best antifungal agent as compared to the standard antibiotics. When the Ag3PO4-FeTiO3/glycol chitosan was used, the amount of inhibition zone was enhanced.


Assuntos
Recuperação e Remediação Ambiental/métodos , Ferro/química , Fosfatos/química , Compostos de Prata/química , Titânio/química , Antibacterianos/farmacologia , Catálise , Quitosana/química , Poluentes Ambientais/química , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Luz , Metronidazol/efeitos adversos , Metronidazol/química , Testes de Sensibilidade Microbiana , Nanocompostos/química , Staphylococcus aureus/efeitos dos fármacos
15.
Chemosphere ; 262: 127886, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805659

RESUMO

Catalytic oxidation is a promising technique to control the emission of gaseous pollutants. Three-dimensionally ordered macroporous (3DOM)-based catalysts have aroused widespread attention because of their high porosity, large surface area and pore volume, superb ability of mass transfer. Therefore, they have been widely used in gaseous pollutants control field, such as soot and methane catalytic combustion, VOCs catalytic oxidation, photocatalytic CO2 reduction and so on. In this review, the recent studies about the preparation and applications of 3DOM catalysts are summarized. At the same time, the advantages and mechanism of the 3DOM catalysts used in gaseous pollutants control are introduced in depth. Finally, the perspective and future direction of 3DOM-based catalysts for gaseous pollutants control are proposed.


Assuntos
Poluentes Ambientais/química , Catálise , Gases , Metano , Oxirredução , Porosidade , Fuligem
16.
Chemosphere ; 262: 128067, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182131

RESUMO

The greatest constraint in the advanced oxidation processes involved Fe(II)/PMS was the low utilization of Fe(II) and PMS. In the present study, the co-catalytic effect of WS2 on the Fe(II)/PMS system for the degradation of organics was investigated. In the presence of WS2, Fe(III) was reduced to Fe(II) during the reaction and resulted in improved decomposition of PMS as well as the degradation of 4-chloriphenol (4-CP). The decomposition rate of PMS and degradation efficiency of 4-CP were 10% and 25% in the Fe(II)/PMS process, while the efficiencies respectively increased to 99% and 100% in the WS2 assisted Fe(II)/PMS system. The degradation of 4-CP was completed via the free radical pathway and SO4•- played a more important role than other active species. Low concentration of inorganic ions such as Cl- and HCO3- exhibited irrelevant effect while humic acid showed significant suppression on the WS2/Fe(II)/PMS system. Additionally, characterization and recycle results implied that WS2 maintained a good stability during the co-catalytic processes.


Assuntos
Compostos Férricos/química , Compostos Ferrosos/química , Sulfetos/química , Compostos de Tungstênio/química , Catálise , Clorofenóis/química , Poluentes Ambientais/química , Modelos Teóricos , Oxirredução , Peróxidos/química
17.
Chemosphere ; 262: 127675, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32805652

RESUMO

With the increasingly serious water environment problem, the persulfate-based advanced oxidation process (PS-AOP) has attracted considerable attention in water pollution treatment. To date, graphitic carbon nitride (g-C3N4) has been greatly favored by researchers in activating PS for its capability and unique superiorities. Though g-C3N4-based PS-AOP exhibits huge development prospects in removing organic pollutants, the review about its research progress has not been reported. Herein, this paper reviews the modification of g-C3N4 on the basis of its applications and properties for PS activation systematically. The activation mechanisms of g-C3N4-based modified materials are analyzed in detail, and the main formation pathways of radicals and non-radicals and their interaction mechanism with pollutants are thoroughly summarized. Finally, the existing challenges and future development directions of the PS-AOP driven by g-C3N4-based materials are critically discussed. The key purpose is to provide a reference for promoting the further popularization of this novel and efficient cooperative AOP in water purification industries, as well as multidisciplinary inspirations for g-C3N4-involved fields.


Assuntos
Poluentes Ambientais/química , Grafite/química , Compostos de Nitrogênio/química , Catálise , Oxirredução , Água
18.
Chemosphere ; 263: 127890, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32814130

RESUMO

Lipids generally represent the major matrix contributing to the absorptive capacity for hydrophobic organic contaminants in aquatic ecosystems. The aim of the present study was to determine whether contaminants partition to a different degree to the different storage lipid classes: wax ester (WE) and triacylglycerol (TAG). This was undertaken by studying experimentally the partitioning of organochlorine compounds between lipids (WE or TAG) and silicone rubber phase. Our results indicate that hydrophobic compounds have a slightly higher affinity for WE than for TAG. The findings thus corroborate earlier suggestions that contaminants accumulate to a greater extent in food webs with a higher reliance of on WE, such as in the Arctic. This knowledge is of interest since it implies that possible changes in planktonic community species composition, and thereby possible changes in the lipid composition, may have consequences for accumulation of hydrophobic contaminants in apex predators. However, the magnitude of these consequences remains unknown, and there may well be other factors of importance for previously observed higher accumulation of contaminants in Arctic systems. Thus, we have here identified aspects regarding partitioning of contaminants to lipids that need further scrutiny, and there is a need for further quantitative estimates of the suggested difference in absorptive capacities for hydrophobic contaminants between WE and TAG.


Assuntos
Poluentes Ambientais/química , Lipídeos/química , Animais , Regiões Árticas , Ecossistema , Cadeia Alimentar , Hidrocarbonetos Clorados/análise , Interações Hidrofóbicas e Hidrofílicas
19.
Chemosphere ; 262: 127738, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32763575

RESUMO

A Pt-Co3O4 catalyst named Pt-Co(OH)2-O was prepared by metal-organic templates (MOTs) conversion and used for catalytic oxidation of toluene. Through the conversion, the morphology of catalysts transformed from rhombic dodecahedron to nanosheet and the coated Pt nanoparticles (NPs) were more exposed. The Binding energy shift in XPS test indicates that the strong metal-support strong interaction (SMSI) has enhanced, and the physicochemical changes caused by it are characterized by other techniques. At the same time, Pt-Co(OH)2-O showed the best catalytic performance (T50 = 157 °C, T90 = 167 °C, Ea = 40.85 kJ mol-1, TOFPt = 2.68 × 10-3 s-1) and good stability. In addition, the in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) studies have shown that because SMSI weakened the Co-O bond, the introduction of Pt NPs can make the migration of oxygen in the catalyst easier. The change of binding energy change and the content of various species in the quasi in situ XPS experiment further confirmed that the Pt-Co(OH)2-O catalyst has stronger SMSI, resulting in its stronger electron transfer ability and oxygen migration ability, which is conducive to catalytic reactions. This work provides new ideas for the development of supported catalysts and provides a theoretical reference for the relevant verification of SMSI.


Assuntos
Cobalto/química , Nanopartículas Metálicas/química , Óxidos/química , Tolueno/química , Catálise , Poluentes Ambientais/química , Oxirredução , Oxigênio/química , Espectroscopia Fotoeletrônica , Platina/química , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Chemosphere ; 261: 128220, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113653

RESUMO

The knowledge about lead (Pb) sorption on soil-derived black carbons (SBCs) under different cultivation intensities of soils is limited. In this study, chemical and spectroscopic methods were applied to investigate the Pb sorption mechanisms on SBCs in soils from a forest land, a rubber plantation area, and a vegetable farm with none, less and highly intensive cultivation, respectively, that are located in the Hainan Island of China. Results showed that the specific surface area and cation exchange capacity of the SBCs from the less and highly intensive cultivation soils were 4.5- and 2.7-fold, and 1.3- and 1.8-fold higher compared to that of SBC from the no-cultivation soil, which subsequently enhanced the Pb sorption capacities of SBCs in iron exchange fraction. Ion exchange and hydrogen bonded Pb fractions together accounted for about 80% of total Pb sorbed on all SBCs at an externally added 1000 mg L-1 Pb solution concentration. The OC-O groups also played key roles in Pb sorption by forming complexes of OC-O-Pb-O and/or OC-O-Pb. Overall, SBCs in soils under all studied cultivation intensities showed high potential to sorb Pb (with the maximum absorbed Pb amount of 46.0-91.3 mg g-1), and increased Pb sorption capacities of the studied soils by 18.7-21.1 mg kg-1 in the stable fraction (complexation). Therefore, SBC might be a potential environment-friendly material to enhance the Pb immobilization capacity of soil.


Assuntos
Poluentes Ambientais/química , Chumbo/química , Solo/química , Fuligem/química , Adsorção , China , Poluentes Ambientais/isolamento & purificação , Ferro , Chumbo/isolamento & purificação
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