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1.
Luminescence ; 39(9): e4901, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39315403

RESUMEN

In this research, the impact of the different zinc (Zn) concentrations on the physical and optoelectronic properties of Bi2S3 nanorods as self-powered and photodiode applications was investigated. The performance of P-N junction photodiodes has been for decades since they are crucial in energy applications. The structure, degree of crystallinity, and shape of Zn-doped Bi2S3 nanorods of various doping percentages formed onto the indium tin oxide (ITO) substrates by the dip coating technique are investigated using X-ray powder diffraction (XRD) and SEM. With increasing illumination time, the current-voltage (I-V) graphs demonstrate a rise in photocurrent. The diode's idealist factor was estimated using the I-V technique under 30 min of light illumination.


Asunto(s)
Bismuto , Nanotubos , Sulfuros , Zinc , Bismuto/química , Zinc/química , Nanotubos/química , Sulfuros/química , Compuestos de Estaño/química , Tamaño de la Partícula , Difracción de Rayos X , Luz
2.
Luminescence ; 39(8): e4840, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39109476

RESUMEN

The study presents Ag2CrO4/Fe2O3/CeO2 ternary nanocomposite, based on Fe2O3/CeO2 binary composites, which demonstrated excellent photocatalytic performance in the photodegradation of methylene blue under solar irradiation. The Ag2CrO4/Fe2O3/CeO2 nanocomposites was orthorhombic, ilmenite, and cubic-fluorite phases of Ag2CrO4, Fe2O3, and CeO2, respectively, according to the XRD examination. A strong bond between Ag2CrO4, Fe2O3, and CeO2 within the nanocomposite was demonstrated by the SEM and TEM investigations. Moreover, it was discovered that the coupling of Ag2CrO4 and Fe2O3 caused a red shift and moved CeO2 absorption edge from the UV to the visible spectrum. The reason behind this is that the band gap of CeO2 reduced 2.85 to 2.69 eV and the absorbance band intensity increased in visible region. Utilizing visible light, Ag2CrO4/Fe2O3/CeO2 ternary nanocomposites exhibit enhanced photocatalytic properties (98.90%) for the degradation of methylene blue (MB) within 100 min. The long-term reliability and recyclability of the photocatalyst were explored through 3 successive cycles. An active radical quenching test was conducted to elucidate the involvement of O2 - and OH which are the primary reactive species in the photocatalytic breakdown of MB. Ag2CrO4/Fe2O3/CeO2 ternary nanocomposites displayed notable improvements in photodegradation activity, making them well suited for the effective removal of hazardous dyes present in textile effluents.


Asunto(s)
Cerio , Compuestos Férricos , Azul de Metileno , Nanocompuestos , Fotólisis , Nanocompuestos/química , Cerio/química , Catálisis , Azul de Metileno/química , Compuestos Férricos/química , Procesos Fotoquímicos , Compuestos de Plata/química , Plata/química , Tamaño de la Partícula
3.
Luminescence ; 39(8): e4849, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39099225

RESUMEN

Pesticides in environmental samples pose significant risks to ecosystems and human health since they require precise and efficient detection methods. Imidacloprid (IMI), a widely used neonicotinoid insecticide, exemplifies these hazards due to its potential toxicity. This study addresses the urgent need for improved monitoring of such contaminants by introducing a novel fluorometric method for detecting IMI using nitrogen-doped graphite carbon dots (N-GCDs). The sensor operates by quenching fluorescence through the interaction of Cu2+ ions with N-GCDs. Subsequently, IMI binds to the imidazole group, chelates with Cu2+, and restores the fluorescence of N-GCDs. This alternating fluorescence behavior allows for the accurate identification of both Cu2+ and IMI. The sensor exhibits linear detection ranges of 20-100 nM for Cu2+ and 10-140 µg/L for IMI, with detection limits of 18 nM and 1.2 µg/L, respectively. The high sensitivity of this sensor enables the detection of real-world samples, which underscores its potential for practical use in environmental monitoring and agricultural safety.


Asunto(s)
Cobre , Monitoreo del Ambiente , Fluorometría , Grafito , Neonicotinoides , Nitrocompuestos , Nitrógeno , Puntos Cuánticos , Neonicotinoides/análisis , Neonicotinoides/química , Nitrocompuestos/química , Nitrocompuestos/análisis , Cobre/química , Cobre/análisis , Nitrógeno/química , Grafito/química , Puntos Cuánticos/química , Insecticidas/análisis , Insecticidas/química , Imidazoles/química
4.
Environ Res ; 258: 119407, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38897435

RESUMEN

The aim of the work is to find the efficiency of solar power in biodiesel preparation from mackerel fish. The paper also focusses on the ability of MgO/graphene prepared by one-pot synthesis using combustion methodology. The physicochemical properties of the material were analysed by XRD, N2 sorption studies, BET sorption analysis and SEM. The adsorption studies revealed the porosity of the graphene is intact, and the morphology studies indicated that MgO is uniformly distributed on the graphene surface. The highest biodiesel yield of 98.95% was obtained using the solar-powered Fresnel solar concentrator at 12.30 p.m in 6 min reaction time using 3 wt% MgO/GO catalyst at 65 °C. Conventional heating produced only 75% biodiesel at the same reaction condition, consuming25 min to complete. The solar assisted biodiesel had better HHV of 37.81 MJ/Kg, viscosity of 4.3 mm2/s, pour point of -15 °C, and a density of 0.875 g/mL. The optimized catalyst showed a shelf life of 5 cycles. The results portray the efficacy of natural energy source in alternative liquid fuel production.


Asunto(s)
Biocombustibles , Grafito , Óxido de Magnesio , Biocombustibles/análisis , Grafito/química , Óxido de Magnesio/química , Catálisis , Animales , Energía Solar
5.
Environ Res ; 258: 119449, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901814

RESUMEN

In the current study, Coccinia grandis fruit extract was used to synthesize calcium oxide nanoparticles (CaO NPs) in an economical and environmentally friendly manner. UV-Vis spectroscopy and Fourier transform infrared spectroscopy revealed that the phytoconstituents found in Coccinia grandis fruit extract facilitated the production of CaO NPs by acting as better stabilizing, biodegradable, and reducing agents. The synthesized CG-CaO NPs were also tested for photocatalytic activity in the breakdown of selective dyes such as methyl red, methyl orange, and methylene blue in the presence of sunlight. The degradation percentage was determined by analyzing the color removal rates for all dye components. After 6 h of reaction, the IC50 values for methyl red, methyl orange, as well as methylene blue dyes were 73, 107, and 133, respectively. The CG-CaO NPs were further evaluated for their antimicrobial activity against specific bacteria and fungi using the agar-well diffusion method. 200 µg/mL CG-CaO NPs inhibited Aspergillus niger, Escherichia coli, Salmonella typhi, Streptococcus mutans, and Staphylococcus aureus at zones of 13, 14, 16, 14, and 15 mM, respectively. Further checkerboard assay confirmed the antagonism effect with gentamicin. Also, Artemia salina toxicity assay showed that the LD50 value of CaO NPs was 400 µg/mL of CaO NPs. The findings confirm that Coccinia grandis-mediated CG-CaO NPs can be used effectively in antimicrobial and environmental settings.


Asunto(s)
Compuestos de Calcio , Colorantes , Cucurbitaceae , Nanopartículas , Óxidos , Extractos Vegetales , Óxidos/química , Compuestos de Calcio/química , Compuestos de Calcio/farmacología , Nanopartículas/química , Cucurbitaceae/química , Colorantes/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Compuestos Azo/química , Animales , Artemia/efectos de los fármacos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Catálisis , Frutas/química , Bacterias/efectos de los fármacos
6.
Environ Res ; 258: 119486, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38925464

RESUMEN

This present study enlightens the eco-friendly green synthesis of ZSM-5 from natural clay montmorillonite, and its proper incorporation with 'Ni'. Nickle (Ni) was wet impregnated onto HZSM-5 and the resulting catalyst was characterized by various techniques including XRD, BET, N2 Sorption Studies, TPD, SEM and TEM techniques. The SEM images revealed the uniform distribution of Ni over HZSM-5 zeolite catalyst and the XRD results indicated the undistorted crystalline structure of HZSM-5 even after impregnation of Ni. The latter part of the work concentrates on the strength of the catalyst in cracking oil derived from discarded fish parts. Discarded fish waste was pyrolyzed to obtain the fish oil, which was then used for cracking studies. The fish oil was efficiently converted (99% conversion) by Ni/ZSM5 (50 wt %) and yielded 70% liquid fractions, which formed gasoline (78.6%), kerosene (12.3%) and diesel (9.1%). The research is a complete parcel to examine the working potential of the produced biofuel in pre-existing engines. The quality of gasoline fraction was tested according to ASTM standards, which showed that the heating value was slightly lower compared to fossil gasoline. The torque and brake fuel consumption were also examined and it indicated that the fish oil derived gasoline fuel may need to be mixed with the commercial gasoline to optimize its performance.


Asunto(s)
Biocombustibles , Aceites de Pescado , Pirólisis , Zeolitas , Biocombustibles/análisis , Zeolitas/química , Catálisis , Aceites de Pescado/química , Níquel/química , Níquel/análisis , Animales
7.
Environ Geochem Health ; 46(8): 261, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38916678

RESUMEN

A simple sol-gel combustion process was employed for the creation of MFe2O4 (M=Ni, Co) nanoparticles. The synthesized nanoparticles, acting as both photocatalysts and gas sensors, were analyzed using various analytical techniques. MFe2O4 (M=Ni, Co) material improved the degradation of methylene blue (MB) under UV-light irradiation, serving as an enhanced electron transport medium. UV-vis studies demonstrated that NiFe2O4 achieved a 60% degradation, while CoFe2O4 nanostructure exhibited a 76% degradation efficacy in the MB dye removal process. Furthermore, MFe2O4 (M=Ni, Co) demonstrated chemosensitive-type sensor capabilities at ambient temperature. The sensor response and recovery times for CoFe2O4 at a concentration of 100 ppm were 15 and 20, respectively. Overall, the synthesis of MFe2O4 (M=Ni, Co) holds the potential to significantly improve the photocatalytic and gas sensing properties, particularly enhancing the performance of CoFe2O4. The observed enhancements make honey MFe2O4 (M=Ni, Co) a preferable choice for environmental remediation applications.


Asunto(s)
Cobalto , Compuestos Férricos , Azul de Metileno , Níquel , Cobalto/química , Cobalto/análisis , Níquel/química , Níquel/análisis , Compuestos Férricos/química , Azul de Metileno/química , Nanopartículas del Metal/química , Gases , Catálisis , Rayos Ultravioleta , Restauración y Remediación Ambiental/métodos , Nanopartículas/química , Óxido de Aluminio , Óxido de Magnesio
9.
Environ Geochem Health ; 46(7): 250, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38877278

RESUMEN

The release of industrial wastewater has adverse effects on both aquatic ecosystems and the environment. Discharging untreated organic dyes into aquatic environments significantly amplifies pollution levels in these ecosystems. Ensuring the appropriate disposal of organic colorants and their derivatives before introducing them into wastewater streams is essential to prevent environmental contamination. This study aimed to develop an eco-friendly and sustainable approach to synthesize a chitosan-functionalized silver (Ag) nanocomposite using Solanum trilobatum for color pollutant mitigation. The synthesized CS-Ag nanocomposite was analyzed using various techniques such as UV-visible, FTIR, TEM, and EDS. TEM analysis revealed that the CS-Ag nanocomposite had a spherical nanostructure, with diameters ranging from 17.4 to 43.9 nm. These nanocomposites were tested under visible light irradiation to analyze their photocatalytic character against Congo red (CR). The nanocomposite exhibited a remarkable dye removal efficiency of over 93.6% within 105 min under irradiation. In the experimental recycling study, the CS-Ag nanocomposites demonstrated remarkable stability and reusability. Furthermore, the CS-Ag nanocomposite exhibited promising inhibition activity against bacterial pathogens. Our research revealed that the synthesized nanocomposite has the potential to act as a highly effective photocatalyst and bactericidal agent in various industrial and clinical applications.


Asunto(s)
Antibacterianos , Quitosano , Colorantes , Nanocompuestos , Plata , Contaminantes Químicos del Agua , Quitosano/química , Nanocompuestos/química , Plata/química , Antibacterianos/farmacología , Antibacterianos/química , Colorantes/química , Contaminantes Químicos del Agua/química , Catálisis , Rojo Congo/química , Restauración y Remediación Ambiental/métodos , Aguas Residuales/química , Luz
10.
Int J Biol Macromol ; 268(Pt 2): 131762, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38657925

RESUMEN

The present investigation describes the development of a novel Chitosan/Polyvinyl Alcohol/Montmorillonite Clay (CS/PVA/MMT) scaffold by adopting an electrospinning method, and their biocompatibility was evaluated in vitro with L929 fibroblast cell line to ascertain its use in wound healing applications. The fabricated scaffold was characterized using analytical techniques. FT-IR measurement exhibited the existence of relevant functional groups and XRD implies scaffolds' amorphous nature. The scaffold's morphology and pore diameter were assessed using TEM and SEM. The pore diameter of the as-prepared scaffold was approximately 125 nm. The antimicrobial assay of the scaffold was evaluated against selected pathogens which demonstrated higher antimicrobial efficacy. The scavenging activity tested using the DPPH assay showed remarkable scavenging capability. The wound healing properties were tested through the Cytotoxicity assay conducted on the L929 assay which proved the scaffold to be a suitable material for cell proliferation. Also, a Molecular docking investigation was carried out for CS/PVA/MMT ligand using human neutrophil elastase (HNE) 1H1B protein as a receptor in the CB-Dock server. Studies conducted in silico revealed strong interaction and high binding energy ratings of CS/PVA/MMT ligand with key residues of human neutrophil elastase (HNE) 1H1B proteins that help in tissue regeneration activity.


Asunto(s)
Bentonita , Proliferación Celular , Quitosano , Simulación del Acoplamiento Molecular , Alcohol Polivinílico , Andamios del Tejido , Alcohol Polivinílico/química , Quitosano/química , Quitosano/farmacología , Bentonita/química , Bentonita/farmacología , Proliferación Celular/efectos de los fármacos , Andamios del Tejido/química , Línea Celular , Ratones , Animales , Humanos , Piel/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Arcilla/química , Ingeniería de Tejidos/métodos
11.
Environ Geochem Health ; 46(5): 172, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38592578

RESUMEN

Advancement in bioinspired alloy nanomaterials has a crucial impact on fuel cell applications. Here, we report the synthesis of PtPd alloy nanoclusters via the hydrothermal method using Piper longum extract, representing a novel and environmentally friendly approach. Physicochemical characteristics of the synthesized nanoclusters were investigated using various instrumentation techniques, including X-ray photoelectron spectroscopy, X-ray diffraction, and High-Resolution Transmission electron microscopy. The electrocatalytic activity of the biogenic PtPd nanoclusters towards the oxidation of formic acid and methanol was evaluated chronoamperometry and cyclic voltammetry studies. The surface area of the electrocatalyst was determined to be 36.6 m2g-1 by Electrochemical Surface Area (ECSA) analysis. The biologically inspired PtPd alloy nanoclusters exhibited significantly higher electrocatalytic activity compared to commercial Pt/C, with specific current responses of 0.24 mA cm - 2 and 0.17 mA cm - 2 at synthesis temperatures of 180 °C and 200 °C, respectively, representing approximately four times higher oxidation current after 120 min. This innovative synthesis approach offers a promising pathway for the development of PtPd alloy nanoclusters with enhanced electrocatalytic activity, thereby advancing fuel cell technology towards a sustainable energy solution.


Asunto(s)
Formiatos , Metanol , Piper , Aleaciones , Extractos Vegetales
12.
Environ Geochem Health ; 46(3): 110, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38460044

RESUMEN

The primary intent of the research is to comprehensively assess the environmental benefits and cost dynamics associated with the adsorption process of CS-RHA (Copper Slag and Rice Husk Ash) to produce a novel geopolymer adsorbent material for application in wastewater treatment. The geopolymer forms a polyiron sialate network under alkali activation by dissolving fayalite, and aluminium silicate to ferro-ferri silicate hydrate gel. The mechanical strength, leaching characteristics, and microstructure of the geopolymer were determined using XRD and FTIR, and magnetic properties by VSM as well surface properties were derived from BET surface area and zeta potential. Recognizing the critical role of sodium iron silicate hydrate (NFS) in the sorption of methylene blue (MB) dyestuff, batch experiments were carried out using different adsorbents. The results indicated that the dye removal efficiency increased from 60% in control samples (FS) to 98% for the blend (FS1) under different pH values. The data was found to fit with the nonlinear form of Freundlich isotherm and follow pseudo-second-order kinetics. The active adsorption sites were deduced as -O-Fe-O-Si-O-Na and Si-OH groups. The addition of RHA increases the adsorption capacity of the geopolymer in a short time through chemical adsorption. The significant negative surface charge promotes MB adsorption via improved electrostatic attraction. The spent adsorbents were recovered through magnetic separation with a retrieval rate of 80-85% and active sites were rejuvenated by calcination. Consequently, waste copper slag emerges as a promising adsorbent with minimum potential ecological risk and high effective recycling capacity.


Asunto(s)
Cobre , Contaminantes Químicos del Agua , Biomasa , Ácido Silícico , Reciclaje , Adsorción , Azul de Metileno/química , Cinética , Concentración de Iones de Hidrógeno , Contaminantes Químicos del Agua/química
13.
Environ Geochem Health ; 46(4): 122, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483653

RESUMEN

This study aims to explore the concentrations of Se and Hg in shellfish along the Gulf of Mannar (GoM) coast (Southeast India) and to estimate related risks and risk-based consumption limits for children, pregnant women, and adults. Se concentrations in shrimp, crab, and cephalopods ranged from 0.256 to 0.275 mg kg-1, 0.182 to 0.553 mg kg-1, and 0.176 to 0.255 mg kg-1, respectively, whereas Hg concentrations differed from 0.009 to 0.014 mg kg-1, 0.022 to 0.042 mg kg-1 and 0.011 to 0.024 mg kg-1, respectively. Se and Hg content in bamboo shark (C. griseum) was 0.242 mg kg-1 and 0.082 mg kg-1, respectively. The lowest and highest Se concentrations were found in C. indicus (0.176 mg kg-1) and C. natator (0.553 mg kg-1), while Hg was found high in C. griseum (0.082 mg kg-1) and low in P. vannamei (0.009 mg kg-1). Se shellfishes were found in the following order: crabs > shrimp > shark > cephalopods, while that of Hg were shark > crabs > cephalopods > shrimp. Se in shellfish was negatively correlated with trophic level (TL) and size (length and weight), whereas Hg was positively correlated with TL and size. Hg concentrations in shellfish were below the maximum residual limits (MRL) of 0.5 mg kg-1 for crustaceans and cephalopods set by FSSAI, 0.5 mg kg-1 for crustaceans and 1.0 mg kg-1 for cephalopods and sharks prescribed by the European Commission (EC/1881/2006). Se risk-benefit analysis, the AI (actual intake):RDI (recommended daily intake) ratio was > 100%, and the AI:UL (upper limit) ratio was < 100%, indicating that all shellfish have sufficient level of Se to meet daily requirements without exceeding the upper limit (UL). The target hazard quotient (THQ < 1) and hazard index (HI < 1) imply that the consumption of shellfish has no non-carcinogenic health impacts for all age groups. However, despite variations among the examined shellfish, it was consistently observed that they all exhibited a Se:Hg molar ratio > 1. This finding implies that the consumption of shellfish is generally safe in terms of Hg content. The health benefit indexes, Se-HBV and HBVse, consistently showed high positive values across all shellfish, further supporting the protective influence of Se against Hg toxicity and reinforcing the overall safety of shellfish consumption. Enhancing comprehension of food safety analysis, it is crucial to recognize that the elevated Se:Hg ratio in shellfish may be attributed to regular selenoprotein synthesis and the mitigation of Hg toxicity by substituting Se bound to Hg.


Asunto(s)
Mercurio , Selenio , Contaminantes Químicos del Agua , Embarazo , Animales , Niño , Adulto , Femenino , Humanos , Mercurio/análisis , Selenio/análisis , Monitoreo Biológico , Peces/metabolismo , Mariscos/análisis , Crustáceos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
14.
Chemosphere ; 349: 140860, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38052312

RESUMEN

Phenanthrene is a persistent organic pollutant released by numerous industries. The purpose of the study is to construct a batch reactor for phenanthrene degradation using a bimetallic (BM) ZnS-SnS nanoparticle as a photocatalyst. ZnS-SnS BM NPs were used as a photocatalyst, employed from precursors Zinc acetate dihydrate and tin (II) chloride dihydrate, with crystalline cubic-shaped particle sizes. ZnS-SnS BM NPs were utilized in batch adsorption assays to assess the impact of phenanthrene degradation parameters on various PAHs (Polycyclic aromatic hydrocarbons) concentrations, pH levels, and irradiation sources. Adsorption kinetic and isotherm tests revealed that the pseudo-first order kinetic model, pseudo-second order kinetic model, and Langmuir isotherm model all fit effectively with the effective phenanthrene degradation using ZnS-SnS BM NPs. The degraded product were analyzed for GC-MS, revealing that organic pollutant phenanthrene was converted into harmless by-products like n-hexadecenoic acid, oleic acid, and octadecanoic acid. The toxicity of phenanthrene was observed to decrease with an increase in ZnS-SnS BM NPs concentration. ZnS-SnS BM NP concentration of 150 µg/mL, the zone of inhibition values was recorded highest zone of inhibition (19 ± 1.2 mm) against the strains S. epidermis followed by B. cereus and Clostridium spp. Further adult zebrafish were found to be less toxic to ZnS-SnS BM NPs after 96 h of exposure, with an LD50 of 100 µg/L. The toxicity escalated as concentrations increased. Behavior test showed normal swimming, learning, and memory in open tank and T-maze tests, while 100 µg/L showed pausing/frozen time in zebra fish therefore low doses are considered safe. Hence by employing ZnS-SnS BM NPs can be engaged in waste water treatment for PAH degradation.


Asunto(s)
Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Animales , Pez Cebra , Adsorción , Fenantrenos/toxicidad , Fenantrenos/química , Hidrocarburos Policíclicos Aromáticos/toxicidad
15.
Chemosphere ; 343: 140075, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37678601

RESUMEN

In this study, a trimetallic nanocomposite comprising Silver Copper-Nickel (Ag-Cu-Ni TNC) was synthesized and analysed for its efficiency in degrading benzene and benzopyrene, which has five fused benzene rings. Fabrication of trimetallic nanocomposites were characterized using UV spectroscopy, FTIR studies, SEM EDAX, and DLS results. XRD confirmed the cubic crystalline Fcc structure of Ag-Cu-Ni TNC. Photocatalytic degradation analysis revealed that Ag-Cu-Ni TNC has the efficient photocatalytic ability, and the optimum condition required for efficient degradation of benzene and benzopyrene was identified as 2 µg/mL of PAH molecule, 10 µg/mL of Ag-Cu-Ni TNC at pH 5, stirring time of 2 h placed under UV light. Based on these optimum conditions, kinetic and isotherm studies were performed, revealing that the adsorption of benzene and benzopyrene by Ag-Cu-Ni TNC fits well with the Pseudo-second order kinetic model and Freundlich isotherm model. Thus, our study's adsorption of PAH molecule from aqueous solution takes place through chemisorption and involves heterogeneous adsorption phenomena.

16.
Environ Res ; 235: 116672, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37453502

RESUMEN

The heavy metals (HMs) in seafood are alarming due to their biomagnification in the food chain. The concentrations of As, Cd, Hg, Pb, Cr, and Ni in both fresh and dried fish were quantified, and the potential exposure and safe intake levels for human consumption were assessed by the European Commission (EC) and the Food Safety Standard Authority of India (FSSAI). HMs concentrations ranged from 0.003 mg/kg (Cr) to 2.08 mg/kg for (As) and 0.007 mg/kg (Hg) to 2.76 mg/kg (As). Cd, Hg, and Pb levels in fresh and dried fish were below the maximum residue limits (MRLs) set by the EC and FSSAI, which were 0.1 mg/kg, 0.5 mg/kg, and 0.3 mg/kg, respectively. Cr and As concentrations were also below the MRLs of 12 mg/kg and 76 mg/kg for aquatic products specified by FSSAI. The concentration of HMs in fresh and dried fish was found in the order of As > Cr > Ni > Pb > Cd > Hg and As > Cd > Cr > Ni > Pb > Hg, while the fresh and dried fishes contained HMs in the following order: E. areolatus > S. longiceps > L.lentjen > S. barracuda > E. affinis > S. javus and DA > DS > DR > DB > DSF. The metal pollution index (MPI) validates seafood is HMs free, while the single (Pi) and Nemerow integrated pollution index (Pnw) indicate that concentrations of Cd and As in fresh and dried fish have exceeded the threshold value. The target hazard quotient (THQ<1), hazard index (HI < 1), and target cancer risk (TCR<10-4) indicate that there are no non-carcinogenic and carcinogenic risks through the consumption of seafood and seafood products collected from the Tuticorin coast and marketed at the domestic and international levels. The preliminary findings emphasize the importance of formulating domestic legislation/government initiatives to promote seafood and its consumption. The attainment of this objective shall be facilitated by examining the levels of persistent organic pollutants (POPs) in seafood and evaluating its potential risk to consumers.


Asunto(s)
Mercurio , Metales Pesados , Contaminantes Químicos del Agua , Animales , Humanos , Cadmio/análisis , Plomo , Alimentos Marinos/análisis , Contaminación de Alimentos/análisis , Medición de Riesgo , Metales Pesados/análisis , Mercurio/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
17.
Environ Res ; 231(Pt 2): 116130, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37201702

RESUMEN

Studies have investigating the detoxification and antioxidant enzymes with melatonin under pesticide stress in many vertebrates, whereas no reports produced in invertebrates. In this study possible role of melatonin and luzindole effect on fipronil toxicity and the detoxification, antioxidant enzymes in H. armigera has been reported. Result showed high toxicity of fipronil treatment (LC50 4.24 ppm), followed by increased LC50 value with melatonin pretreatment (6.44 ppm). Whereas decreased toxicity was observed with melatonin and luzindole combination (3.72 ppm). The detoxification enzymes AChE, esterase and P450 were increased in larval head and whole body with exogenous melatonin level compared to control 1-1.5 µmol/mg of protein. The antioxidant levels of CAT, SOD and GST in whole body and head tissue had been increased by melatonin and fipronil combination 1.1-1.4 unit/mg of protein followed by GPx and GR in larval head (1-1.2 µmol/mg of protein). Mean while the luzindole antagonist inhibits CAT, SOD, GST and GR oxidative enzyme level (1-1.5 fold) in most of the tissue compared to melatonin and fipronil treatment (p < 0.01). Hence this study concludes that the melatonin pretreatment can reduce the fipronil toxicity by enhanced detoxification and antioxidant enzyme system in H. armigera.


Asunto(s)
Melatonina , Mariposas Nocturnas , Animales , Antioxidantes/farmacología , Melatonina/farmacología , Larva/metabolismo , Mariposas Nocturnas/metabolismo , Superóxido Dismutasa/metabolismo
18.
Environ Res ; 231(Pt 1): 116033, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37142082

RESUMEN

The current study aimed to investigate the effects of lead nitrate exposure on the enzymatical, haematological, and histological changes in the gill, liver, and kidney of Pangasius hypophthalmus. The fish were divided into six groups and treated with different Pb concentrations. The LC50 value of Pb was 55.57 mg/L at 96 h for P. hypophthalmus, and sublethal toxicity was assessed for 45 days at 1/5th (11.47 mg/L) and 1/10th (5.57 mg/L) of LC50 concentration. Enzymes such as aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, alkaline phosphate (ALP), and lactate dehydrogenase (LDH) content increased significantly during sublethal toxicity of Pb. The reduction of HCT and PCV indicates an anemic condition due to the toxicity of Pb. Differential leucocytes, lymphocytes, and monocytes and their % values significantly decreased, indicating Pb exposure. The main histological changes observed in the gills were the destruction of secondary lamellae, the fusion of adjacent gill lamellae, primary lamellae hypertrophy, and severe hyperplasia, while in kidney exposed to Pb showed melanomacrophages, increased periglomerular, peritubular space, vacuolation, shrunken glomerulus, destruction of tubular epithelium, and hypertrophy of distal convoluted segment. The liver showed severe necrosis and rupture of hepatic cells, hyper trepheoid bile duct, shifting of nuclei, and vascular hemorrhage, while in the brain, binucleus, mesoglea cells, vacuole, and ruptured nucleus were observed. In conclusion, P. hypophthalmus, which has been exposed to Pb has developed a number of toxicity markers. Consequently, prolonged exposure to higher Pb concentrations may be harmful to fish health. The findings strongly suggest that the lead had a detrimental impact on the P. hypophthalmus population, as well as on the water quality and non-target aquatic organisms.


Asunto(s)
Bagres , Metales Pesados , Contaminantes Químicos del Agua , Animales , Plomo/toxicidad , Metales Pesados/toxicidad , Antioxidantes/farmacología , Hígado , Branquias , Contaminantes Químicos del Agua/toxicidad
19.
Environ Res ; 225: 115602, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36863656

RESUMEN

The impact of ZnO/SnO2/reduced graphene oxide nanocomposites (ZnO/SnO2/rGO NCs) for improved photocatalytic degradation of organic dye pollution is examined in this study. The developed ternary nanocomposites had a variety of characteristics that were detected, such as crystallinity, recombination of photogenerated charge carriers, energy gap, and surface morphologies. When rGO was added to the mixture, the optical band gap energy of ZnO/SnO2 was lowered, which improved the photocatalytic activity. Additionally, in comparison to ZnO, ZnO/rGO, SnO2/rGO samples, the ZnO/SnO2/rGO nanocomposites demonstrated exceptional photocatalytic effectiveness for the destruction of orange II (99.8%) and reactive red 120 dye (97.02%), respectively after 120 min exposure to sunlight. The high electron transport properties of the rGO layers, which make it feasible to efficiently separate electron-hole pairs, are attributed to the enhanced photocatalytic activity of the ZnO/SnO2/rGO nanocomposites. According to the results, synthesized ZnO/SnO2/rGO nanocomposites are a cost-efficient option for removing dye pollutants from an aqueous ecosystem. Studies show that ZnO/SnO2/rGO nanocomposites are effective photocatalysts and may one day serve as the ideal material to reduce water pollution.


Asunto(s)
Contaminantes Ambientales , Nanocompuestos , Óxido de Zinc , Ecosistema
20.
Environ Res ; 233: 115601, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36863657

RESUMEN

The advancement of effective and long-lasting electrocatalysts for energy storage devices is crucial to reduce the impact of the energy crisis. In this study, a two-stage reduction process was used to synthesize carbon-supported cobalt alloy nanocatalysts with varying atomic ratios of cobalt, nickel and iron. The formed alloy nanocatalysts were investigated using energy-dispersive X-ray spectroscopy, X-ray diffraction, and transmission electron microscopy to determine their physicochemical characterization. According to XRD results, Cobalt-based alloy nanocatalysts form a face-centered cubic solid solution pattern, illustrating thoroughly mixed ternary metal solid solutions. Transmission electron micrographs also demonstrated that samples of carbon-based cobalt alloys displayed homogeneous dispersion at particle sizes ranging from 18 to 37 nm. Measurements of cyclic voltammetry, linear sweep voltammetry, and chronoamperometry revealed that iron alloy samples exhibited much greater electrochemical activity than non-iron alloy samples. The alloy nanocatalysts were evaluated as anodes for the electrooxidation of ethylene glycol in a single membraneless fuel cell to assess their robustness and efficiency at ambient temperature. Remarkably, in line with the results of cyclic voltammetry and chronoamperometry, the single-cell test showed that the ternary anode works better than its counterparts. The significantly higher electrochemical activity was observed for alloy nanocatalysts containing iron than for non-iron alloy catalysts. Iron stimulates nickel sites to oxidize cobalt to cobalt oxyhydroxides at lower over-potentials, which contributes to the improved performance of ternary alloy catalysts containing iron.


Asunto(s)
Glicol de Etileno , Níquel , Cobalto , Aleaciones/química , Carbono/química
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