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1.
Environ Sci Pollut Res Int ; 31(26): 38196-38216, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38795297

RESUMO

Finding a cost-effective, efficient, and environmentally friendly technique for the removal of mercury ion (Hg2+) in water and wastewater can be a challenging task. This paper presents a novel and efficient adsorbent known as the graphene oxide-Cu2SnS3-polyaniline (GO-CTS-PANI) nanocomposite, which was synthesised and utilised to eliminate Hg2+ from water samples. The soft-soft interaction between Hg2+ and sulphur atoms besides chelating interaction between -N and Hg2+ is the main mechanism for Hg2+ adsorption onto the GO-CTS-PANI adsorbent. Various characterisation techniques, including Fourier transform infrared spectrophotometry (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), elemental mapping analysis, and X-ray diffraction analysis (XRD), were employed to analyse the adsorbent. The Box-Behnken method, utilising Design Expert Version 7.0.0, was employed to optimise the crucial factors influencing the adsorption process, such as pH, adsorbent quantity, and contact time. The results indicated that the most efficient adsorption occurred at pH 6.5, with 12 mg of GO-CTS-PANI adsorbent, and 30-min contact time that results in a maximum removal rate of 95% for 50 mg/L Hg2+ ions. The study also investigated the isotherm and kinetics of the adsorption process that the adsorption of Hg2+ onto the adsorbent happened in sequential layers (Freundlich isotherm) and followed by the pseudo-second-order kinetic model. Furthermore, response surface methodology (RSM) analysis indicates that pH is the most influential parameter in enhancing adsorption efficiency. In addition to traditional models, this study employed some artificial intelligence (AI) methods including the Random Forest algorithm to enhance the prediction of adsorption process efficiency. The findings demonstrated that the Random Forest algorithm exhibited high accuracy with a correlation coefficient of 0.98 between actual and predicted adsorption rates. This study highlights the potential of the GO-CTS-PANI nanocomposite for effectively removing of Hg2+ ions from water resources.


Assuntos
Compostos de Anilina , Grafite , Mercúrio , Nanocompostos , Poluentes Químicos da Água , Mercúrio/química , Grafite/química , Nanocompostos/química , Adsorção , Compostos de Anilina/química , Poluentes Químicos da Água/química , Cinética , Cobre/química , Purificação da Água/métodos
2.
Environ Sci Pollut Res Int ; 31(26): 38416-38427, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38802616

RESUMO

Classical monitoring of air pollution provides information on environmental quality but involves high costs. An alternative to this method is the use of bioindicators. The purpose of our work was to evaluate atmospheric aerosol pollution by selected polycyclic aromatic hydrocarbons conducted as part of annual active biomonitoring ("moss-bag" technique) with the use of three moss species: Pleurozium schreberi, Sphagnum fallax, and Dicranum polysetum. The gas chromatography-mass spectrometry (GC-MS) was utilized to determine certain 13 polycyclic aromatic hydrocarbons (PAHs). Three seasonal variations in PAH concentrations have been observed as a result of the study. A fire on the toilet paper plant caused an increase of five new compounds: benzo(k)fluoranthene (BkF), benzo(a)pyrene (BaP), indeno(1.2.3)-cd_pyrene (IP), dibenzo(a.h)anthracene (Dah), and benzo(g.h.i)perylene (Bghi) in proximity after 8 months of exposure compared to previous months. The effect of meteorological conditions on the deposition of PAHs (mainly wind direction) in mosses was confirmed by principal component analysis (PCA). Dicranum polysetum moss accumulated on average 26.5% more PAHs than the other species, which allows considering its broader use in active biomonitoring. The "moss-bag" technique demonstrates its feasibility in assessing the source of PAH air pollution in a long-term study. It is recommended to use this biological method as a valuable tool in air quality monitoring.


Assuntos
Poluentes Atmosféricos , Monitoramento Biológico , Briófitas , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Biológico/métodos , Briófitas/química , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição do Ar , Cromatografia Gasosa-Espectrometria de Massas , Estações do Ano
3.
J Phys Chem Lett ; 15(15): 4006-4014, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38574347

RESUMO

One-dimensional transition metal materials are promising supports for precious metals used in energy production processes. Due to their electrochemical properties, 3d-group metals (such as Ni, Co, and Fe) can actively interact with catalysts by a strong metal-support interaction. This study shows that changing the Ni:Co ratio makes it possible to modulate the structure of the catalyst supports, which, in turn, provides a tool for designing their electrical and electrochemical properties. For example, Ni1-Co9 shows the highest electrical conductivity (5.8-10-4 S/cm) among all of the materials examined. On the contrary, the Pd@Ni7-Co3 system presents the highest mass activity (>2000 mA mg-1) at 0.7 V, exceeding by several times that of commercial Pt/C (>300 mA mg-1) at the same potential. Our study opens the gateway for applications of bimetallic transition metal nanowires in catalytic conversion and energy production processes.

4.
Heliyon ; 10(3): e25036, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38317976

RESUMO

This study presents an intelligent Decision Support System (DSS) aimed at bridging the theoretical-practical gap in groundwater management. The ongoing demand for sophisticated systems capable of interpreting extensive data to inform sustainable groundwater decision-making underscores the critical nature of this research. To meet this challenge, telemetry data from six randomly selected wells were used to establish a comprehensive database of groundwater pumping parameters, including flow rate, pressure, and current intensity. Statistical analysis of these parameters led to the determination of threshold values for critical factors such as water pressure and electrical current. Additionally, a soft sensor was developed using a Random Forest (RF) machine learning algorithm, enabling real-time forecasting of key variables. This was achieved by continuously comparing live telemetry data to pump design specifications and results from regular field testing. The proposed machine learning model ensures robust empirical monitoring of well and pump health. Furthermore, expert operational knowledge from water management professionals, gathered through a Classical Delphi (CD) technique, was seamlessly integrated. This collective expertise culminated in a data-driven framework for sustainable groundwater facilities monitoring. In conclusion, this innovative DSS not only addresses the theory-application gap but also leverages the power of data analytics and expert knowledge to provide high-precision online insights, thereby optimizing groundwater management practices.

5.
Sci Rep ; 14(1): 2336, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38282019

RESUMO

Conjugated polymers are promising tools to differentiate various types of semiconducting single-walled carbon nanotubes (s-SWCNTs). However, their synthesis is challenging. Insufficient control over molecular weights, and unpredictive/unrepeatable batches hinder possible applications and scale-up. Furthermore, commercial homogeneous catalysts often require inert conditions and are almost impossible to recycle. To overcome these problems, we present a nanocatalyst consisting of magnetic nickel nanowires decorated with highly active palladium nanoparticles. A two-step wet chemical reduction protocol with the assistance of sonochemistry was employed to obtain a heterogeneous catalyst capable of conducting step-growth Suzuki polycondensation of a fluorene-based monomer. Additionally, we enhanced the performance of our catalytic system via controlled microwave irradiation, which significantly shortened the reaction time from 3 d to only 1 h. We studied the influence of the main process parameters on the yield and polymer chain length to gain insight into phenomena occurring in the presence of metallic species under microwave irradiation. Finally, the produced polymers were used to extract specific s-SWCNTs by conjugated polymer extraction to validate their utility.

6.
Pharmaceuticals (Basel) ; 16(8)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37630991

RESUMO

Mosses (Bryophyta), particularly species of the genus Sphagnum, which have been used for centuries for the treatment of skin diseases and damage, are still not explored enough in terms of their use in cosmetics. The purpose of this study was to determine the antioxidant properties of water-ethanol extracts from four selected species of the genus Sphagnum (S. girgenshonii Russow, S. magellanicum Brid., S. palustre L., and S. squarrosum Crome) and their impact on the expression of genes encoding key enzymes for the functioning of the skin. In this study, the effects of Sphagnum extracts on the expression of genes encoding tyrosinase, collagenase, elastase, hyaluronidase and hyaluronic acid synthase in human dermal fibroblasts were determined for the first time in vitro. The extracts inhibited tyrosinase gene expression and showed antioxidant activity. The experiment showed an increase in the expression of some genes encoding collagenase (MMP1) or hyaluronidase (HYAL2, HYAL3 and HYAL4) and a decrease in the hyaluronan synthase (HAS1, HAS2 and HAS3) genes expression by the tested extracts. The obtained results suggest that using extracts from the tested Sphagnum species in anti-aging cosmetics does not seem beneficial. Further studies are needed to clarify their impact on the skin.

7.
Ecotoxicol Environ Saf ; 263: 115269, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37478568

RESUMO

Chromium (Cr) pollution caused by the discharge of industrial wastewater into rivers poses a significant threat to the environment, aquatic and human life, as well as agricultural crops irrigated by these rivers. This paper employs artificial intelligence (AI) to introduce a new framework for modeling the fate, transport, and estimation of Cr from its point of discharge into the river until it is absorbed by agricultural products. The framework is demonstrated through its application to the case study River, which serves as the primary water resource for tomato production irrigation in Mashhad city, Iran. Measurements of Cr concentration are taken at three different river depths and in tomato leaves from agricultural lands irrigated by the river, allowing for the identification of bioaccumulation effects. By employing boundary conditions and smart algorithms, various aspects of control systems are evaluated. The concentration of Cr in crops exhibits an accumulative trend, reaching up to 1.29 µg/g by the time of harvest. Using data collected from the case study and exploring different scenarios, AI models are developed to estimate the Cr concentration in tomato leaves. The tested AI models include linear regression (LR), neural network (NN) classifier, and NN regressor, yielding goodness-of-fit values (R2) of 0.931, 0.874, and 0.946, respectively. These results indicate that the NN regressor is the most accurate model, followed by the LR, for estimating Cr levels in tomato leaves.


Assuntos
Cromo , Metais Pesados , Humanos , Cromo/análise , Rios , Metais Pesados/análise , Produtos Agrícolas , Inteligência Artificial , Irã (Geográfico) , Monitoramento Ambiental
8.
Sci Rep ; 13(1): 12200, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500665

RESUMO

Water Distribution Networks (WDNs) are considered one of the most important water infrastructures, and their study is of great importance. In the meantime, it seems necessary to investigate the factors involved in the failure of the urban water distribution network to optimally manage water resources and the environment. This study investigated the impact of influential factors on the failure rate of the water distribution network in Birjand, Iran. The outcomes can be considered a case study, with the possibility of extending to any similar city worldwide. The soft sensor based on the Adaptive Neuro-Fuzzy Inference System (ANFIS) was implemented to predict the failure rate based on effective features. Finally, the WDN was assessed using the Failure Modes and Effects Analysis (FMEA) technique. The results showed that pipe diameter, pipe material, and water pressure are the most influential factors. Besides, polyethylene pipes have failure rates four times higher than asbestos-cement pipes. Moreover, the failure rate is directly proportional to water pressure but inversely related to the pipe diameter. Finally, the FMEA analysis based on the knowledge management technique demonstrated that pressure management in WDNs is the main policy for risk reduction of leakage and failure.

9.
Pharmaceutics ; 15(6)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37376137

RESUMO

Naproxen is one of the most used non-steroidal anti-inflammatory drugs (NSAIDs). It is used to treat pain of various origins, inflammation and fever. Pharmaceutical preparations containing naproxen are available with prescription and over-the-counter (OTC). Naproxen in pharmaceutical preparations is used in the form of acid and sodium salt. From the point of view of pharmaceutical analysis, it is crucial to distinguish between these two forms of drugs. There are many costly and laborious methods to do this. Therefore, new, faster, cheaper and, at the same time, simple-to-perform identification methods are sought. In the conducted studies, thermal methods such as thermogravimetry (TGA) supported by calculated differential thermal analysis (c-DTA) were proposed to identify the type of naproxen in commercially available pharmaceutical preparations. In addition, the thermal methods used were compared with pharmacopoeial methods for the identification of compounds, such as high-performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectrophotometry, and a simple colorimetric analyses. In addition, using nabumetone, a close structural analog of naproxen, the specificity of the TGA and c-DTA methods was assessed. Studies have shown that the thermal analyses used are effective and selective in distinguishing the form of naproxen in pharmaceutical preparations. This indicates the potential possibility of using TGA supported by c-DTA as an alternative method.

10.
Sci Rep ; 13(1): 7860, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37188707

RESUMO

Magnetite nanoparticles (Fe3O4 NPs) are widely tested in various biomedical applications, including magnetically induced hyperthermia. In this study, the influence of the modifiers, i.e., urotropine, polyethylene glycol, and NH4HCO3, on the size, morphology, magnetically induced hyperthermia effect, and biocompatibility were tested for Fe3O4 NPs synthesized by polyol method. The nanoparticles were characterized by a spherical shape and similar size of around 10 nm. At the same time, their surface is functionalized by triethylene glycol or polyethylene glycol, depending on the modifiers. The Fe3O4 NPs synthesized in the presence of urotropine had the highest colloidal stability related to the high positive value of zeta potential (26.03 ± 0.55 mV) but were characterized by the lowest specific absorption rate (SAR) and intrinsic loss power (ILP). The highest potential in the hyperthermia applications have NPs synthesized using NH4HCO3, for which SAR and ILP were equal to 69.6 ± 5.2 W/g and 0.613 ± 0.051 nHm2/kg, respectively. Their application possibility was confirmed for a wide range of magnetic fields and by cytotoxicity tests. The absence of differences in toxicity to dermal fibroblasts between all studied NPs was confirmed. Additionally, no significant changes in the ultrastructure of fibroblast cells were observed apart from the gradual increase in the number of autophagous structures.


Assuntos
Hipertermia Induzida , Nanopartículas de Magnetita , Nanopartículas de Magnetita/química , Polímeros , Polietilenoglicóis/química , Hipertermia Induzida/métodos
11.
Environ Res ; 229: 115910, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37062479

RESUMO

Sulfate radical-based advanced oxidation processes (SR-AOPs) are gaining popularity as a feasible alternative for removing recalcitrant pollutants in an aqueous environment. Persulfates, namely peroxydisulfate (PDS) and peroxymonosulfate (PMS) are the most common sulfate radical donors. Persulfates activation by ultraviolet (UV) irradiation is considered feasible due to the high concentration of radicals produced as well as the lack of catalysts leaching. The research focuses on determining the impact of activated PDS and PMS on the degradation of anthraquinone dye, i.e., Acid Blue 129 (AB129). UV-activated PDS and PMS can quickly degrade the AB129 as well as restrict the formation of by-products. This could explain the reduced ecotoxicity levels of the treated water after degradation, using an aquatic plant (Lemna minor) and a crustacean (Daphnia magna). This, on the other hand, can ensure that the sulfate radical-based processes can be an environmentally friendly technology.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cinética , Poluentes Químicos da Água/análise , Oxirredução , Antraquinonas
12.
J Hazard Mater ; 445: 130626, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36588018

RESUMO

UV-E-chlorination/hematite nanoparticles (UV/E-Cl/HNs) as a heterogeneous photocatalytic activation of electrogenerated chlorine was assessed for the degradation of bisphenol A (BPA) as a new approach based on the generation of reactive chlorine and oxygen species. The prepared sample was characterized using multiple techniques, such as XRD, FTIR, FESEM, EDS, and BET-BJH. An excellent decontamination efficiency of 99.4% was achieved within 40 min of electrolysis under optimum conditions (pH of 5, HNs dosage 100 mg/L, current density of 20 mA/cm2, and NaCl concentration of 50 mM). The HOCl content was reduced more swiftly in the presence of ultraviolet (UV) irradiation and hematite, resulting in the production of oxidative radicals (i.e., •OH, Cl•, and Cl2•-). The scavenging experiments also verified the vital role of these radicals in oxidative treatment. The UV/E-Cl/HNs process is readily supplied with hydroxyl radicals through several mechanisms. Bicarbonate ions showed a noticeable inhibitory impact, whereas nitrate and sulfate anions only slightly affected BPA degradation. The HNs were a recoverable and stable catalyst for six cycles. Furthermore, the ECOSAR program predicted that the UV/E-Cl/HNs can be labeled as an environmental-friendly process. Eventually, reasonable degradation pathways were proposed based on the identified by-products through experimental and theoretical approaches.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro/química , Águas Residuárias , Oxigênio , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cloretos , Raios Ultravioleta , Oxirredução , Cinética
13.
Biology (Basel) ; 11(12)2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36552202

RESUMO

The interrelationship between metal concentrations in mosses and their surroundings prompts research toward examining their accumulation properties, as it is particularly important for their usage in biomonitoring studies that use mosses. In this study, the kinetics of elemental sorption in three moss species (Pleurozium schreberi, Dicranum polysetum, and Sphagnum fallax) were investigated under laboratory conditions. Sorption from metal salt solutions was carried out under static conditions with decreasing elemental concentration. Functional groups responsible for binding metal cations to the internal structures of the mosses were also identified. It was shown that the equilibrium state was reached after about 60 min. Under the conditions of the experiment, in the first 10 min of the process, about 70.4-95.3% of metal ions were sorbed from the solution into the moss gametophytes by P. schreberi (57.1-89.0% by D. polysetum and 54.1-84.5% by S. fallax) with respect to the concentration of this analyte accumulated in the mosses at equilibrium. It can be assumed that the exposure of mosses with little contamination by heavy metals in an urbanized area under active biomonitoring will cause an increase in the concentration of these analytes in proportion to their concentration in atmospheric aerosols. In the case of P. schreberi and D. polysetum, the O-H/N-H band was enormously affected by the adsorption process. On the other hand, FTIR (Fourier transform infrared spectroscopy) analysis of S. fallax after adsorption showed slight changes for most of the bands analyzed. Based on this study, it can be concluded that mosses can be used as, for example, a biomonitor in monitoring of urban ecosystems, but also in the phytoremediation of surface waters.

14.
Adv Colloid Interface Sci ; 310: 102807, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36384078

RESUMO

Water could be considered one of the essential natural resources on our planet. However, water contamination has become virtually ubiquitous during the past decades due to several factors, e.g., world population growth, water use in chemical production, and agriculture. Among contaminants, persistent organic pollutants (POPs) were widely spread during the last few decades and are now present all around the world. POPs are connected with several different illnesses, and therefore the removal of these pollutants from water is a challenge for coming years. Cyclodextrins (CDs) are environmentally friendly and cheap pollutant adsorbents due to their peculiar physicochemical properties. Moreover, CDs are relatively easy to use, and many techniques are reported for their functionalization. In addition, several CD derivatives are known and some of them are commercially available. CDs and CD-functionalized materials could be used for removal of different pollutants by using various methods, e.g., adsorption/extraction, soil washing, and electrokinetic/catalytic processes. This is the first review article that provides an overview of CDs/CD-based materials and their use in the remediation of POPs listed under the Stockholm Convention. The mechanisms of the POPs removal by CDs are also discussed.


Assuntos
Ciclodextrinas , Poluentes Ambientais , Poluentes Orgânicos Persistentes , Ciclodextrinas/química , Adsorção , Água
15.
Polymers (Basel) ; 14(15)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35956636

RESUMO

The accumulation of organic contaminants including dyes in aquatic systems is of significant environmental concern, necessitating the development of affordable and sustainable materials for the treatment/elimination of these hazardous pollutants. Here, a green synthesis strategy has been used to develop a self-assembled gum kondagogu-sodium alginate bioconjugate sponge adorned with silver nanoparticles, for the first time. The properties of the nanocomposite sponge were then analyzed using FTIR, TGA, SEM, and MicroCT. The ensued biobased sponge exhibited hierarchical microstructure, open cellular pores, good shape memory, and mechanical properties. It merges the attributes of an open cellular porous structure with metal nanoparticles and are envisaged to be deployed as a sustainable catalytic system for reducing contaminants in the aqueous environment. This nanocomposite sponge showed enhanced catalytic effectiveness (km values up to 37 min-1 g-1 and 44 min-1 g-1 for methylene blue and 4-nitrophenol, respectively), antibacterial properties, reusability, and biodegradability (65% biodegradation in 28 days).

16.
Artigo em Inglês | MEDLINE | ID: mdl-35457569

RESUMO

Recently, significant attention has been paid to air quality awareness and its impact on human health, especially in urban agglomerations. Many types of dust samplers for air quality monitoring are used by governmental environmental monitoring agencies. However, these techniques are associated with high costs; as a consequence, biological methods such as active moss biomonitoring are being developed. The main disadvantages of such techniques are the lack of standardization of the preparation procedures and the lack of reliable comparisons of results with data from instrumental analyses. Our study aimed to compare the results obtained from active biomonitoring with the use of three moss species: Pleurozium schreberi, Sphagnum fallax and Dicranum polysetum. Samples were exposed via the moss-bag technique to measure the concentrations of analytes (Mn, Fe, Cu, Zn, Cd, Hg and Pb) which had accumulated among the total suspended particulates (TSP) collected from the filters of a dust collector in the city of Opole (Opole voivodeship, Poland). With regard to the physicochemical and biological traits of the mosses, their assessed lifetime and actual photochemical efficiency (yield) following exposure were meagre, which may have been related to the change of environment and their exposure to pollutants. When comparing the results obtained by the two methods used to monitor air pollution, the biomonitoring method was found to be incompletely consistent with the reference method. Biological monitoring using mosses must be carefully considered depending on the monitoring objectives, the required level of sensitivity and quality of measurement and the type of pollutant.


Assuntos
Filtros de Ar , Poluentes Atmosféricos , Briófitas , Bryopsida , Poluentes Ambientais , Metais Pesados , Poluentes Atmosféricos/análise , Monitoramento Biológico , Poeira/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Humanos , Metais Pesados/análise
17.
Polymers (Basel) ; 14(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35160453

RESUMO

Green bionanocomposites have garnered considerable attention and applications in the pharmaceutical and packaging industries because of their intrinsic features, such as biocompatibility and biodegradability. The work presents a novel approach towards the combined effect of glycerol, tween 80 and silver nanoparticles (AgNPs) on the physicochemical properties of lyophilized chitosan (CH) scaffolds produced via a green synthesis method.The produced bionanocomposites were characterized with the help of Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The swelling behavior, water vapor transmission rate, moisture retention capability, degradation in Hanks solution, biodegradability in soil, mechanical strength and electrochemical performance of the composites were evaluated. The addition of additives to the CH matrix alters the physicochemical and biological functioning of the matrix. Plasticized scaffolds showed an increase in swelling degree, water vapor transmission rate and degradability in Hank's balanced solution compared to the blank chitosan scaffolds. The addition of tween 80 made the scaffolds more porous, and changes in physicochemical properties were observed. Green-synthesized AgNPs showed intensified antioxidant and antibacterial properties. Incorporating biogenic nanoparticles into the CH matrix enhances the polymer composites' biochemical properties and increases the demand in the medical and biological sectors. These freeze-dried chitosan-AgNPs composite scaffolds had tremendous applications, especially in biomedical fields like wound dressing, tissue engineering, bone regeneration, etc.

18.
Sci Total Environ ; 817: 152888, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-34998775

RESUMO

Rising concern about emerging and already persisting pollutants in water has urged the scientific community to develop novel remedial techniques. A new group of remediation methods is based on the modification of nanoscale zero-valent iron particles (nZVI), which are well known for treating volatile organic compounds and heavy metals. The properties of nZVI may be further enhanced by modifying their structure or surface using "green" polymers. Herein, nZVI was modified by a ß-cyclodextrin polymer (ß-CDP), which is considered an environmentally safe and inexpensive adsorbent of contaminants. This composite was used for the first time for the degradation of sulfamethoxazole (SMX). Coating by ß-CDP not only enhanced the degradation of SMX (>95%, under 10 min) by the nanoparticles in a wide pH range (3-9) and enabled their efficient reusability (for three cycles) but also made the coated nZVI less toxic to the model bioindicator microalga Raphidocelis subcapitata. Moreover, degradation products of SMX were found to be less toxic to Escherichia coli bacteria and R. subcapitata microalga, contrary to the SMX antibiotic itself, indicating a simple and eco-friendly cleaning process. This research aims to further stimulate and develop novel remedial techniques based on nZVI, and provides a potential application in the degradation of antibiotics in a wide pH range. Moreover, the wealth of available cyclodextrin materials used for surface modification may open a way to discover more efficient and attractive composites for environmental applications.


Assuntos
Ciclodextrinas , Metais Pesados , Poluentes Químicos da Água , Celulose , Ferro/química , Sulfametoxazol/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
19.
Water Res ; 212: 118101, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35092911

RESUMO

Studies related to advanced reduction technologies (ARTs) have grown exponentially since the term was first coined in 2013. Despite recent interests in ARTs, the conditions and requirements for these processes have yet to be defined and clarifed. In comparision to well defined advanced oxidation technologies/processes (AOTs/AOPs) which involve the generation of hydroxyl radical as the common characteristic, ARTs function by electron donation from a variety of reducing agents and activators. Based on an extensive literature review, we propose that ARTs be defined as processes employing strong chemical reductants with E° ≤ -2.3 V vs. normal hydrogen electrode at 25 ºC. While extensive studies have revealed critical fundamental details of AOTs/AOPs mediated processes, there are still significant gaps in elucidation of the mechanistic details of reductive degradation/transformation of highly toxic compounds by ARTs. A significant number of pollutants and toxins resistant to AOTs/AOPs treatment are effectively degraded by ARTs. A great leap is needed on understanding ARTs to fully utilize their potential to efficiently remediate recalcitrant compounds of different sources and structures.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Peróxido de Hidrogênio , Radical Hidroxila , Oxirredução , Poluentes Químicos da Água/análise
20.
Molecules ; 26(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34885844

RESUMO

The use of biological indicators of environmental quality is an alternative method of monitoring ecosystem pollution. Various groups of contaminants, including organic ones, can be measured in environmental samples. Polycyclic aromatic hydrocarbons (PAHs) have not yet been determined by the moss bag technique. This technique uses several moss species simultaneously in urban areas to select the best biomonitoring of these compounds, which are dangerous to humans and the environment. In this research, a gas chromatography coupled with mass spectrometry was used for the determination of selected PAHs in three species of mosses: Pleurozium schreberi, Sphagnum fallax and Dicranum polysetum (active biomonitoring) and for comparison using an air filter reference method for atmospheric aerosol monitoring. The chlorophyll fluorescence of photosystem II (PSII) was also measured to assess changes in moss viability during the study. As a result of the study, the selective accumulation of selected PAHs by mosses was found, with Pleurozium schreberi being the best bioindicator-9 out of 13 PAHs compounds were determined in this species. The photosynthetic yield of photosystem (II) decreased by 81% during the exposure time. The relationship between PAHs concentrations in mosses and the total suspended particles (TSP) on the filter indicated the possibility of using this bioindicator to trace PAHs in urban areas and to apply the moss bag technique as a method supporting classical instrumental air monitoring.


Assuntos
Aerossóis/análise , Atmosfera/química , Monitoramento Biológico , Briófitas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/análise , Análise por Conglomerados , Filtração
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