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1.
Sci Rep ; 14(1): 16259, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009639

RESUMO

A metal-free combination of rGO/g-C3N4-coupled SrTiO3 (SRN) ternary nanocomposite prepared via a wet impregnation method for UV-Vis light photocatalytic applications. Various physicochemical properties of the samples were investigated by several spectroscopic techniques including X-ray diffraction (XRD), FT-IR, Raman, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy (FE-SEM-EDX), high-resolution transmission electron microscopy (HR-TEM), UV-Vis, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analysis. The data suggest agglomerated SRT nanoparticles are dispersed and distributed throughout the surface of the rGO sheets and GCN nanostructures. The photocatalytic performance of the SRN towards combined mixed dye and its degradation activities were evaluated towards the most common industrial effluents, Rhodamine B (RhB) and Methylene blue (MB), under UV-Vis light illumination. The results revealed that the degradation efficiency of the SRN photocatalyst shows excellent performance compared with that of the binary composition and the pure SrTiO3 (SRT) sample. The reaction rate constant for RhB was estimated to be 0.0039 min-1 and for MB to be 0.0316 min-1, which are 3.26 (RhB) and 4.21 (MB) times faster than the pure SRT sample. The enhanced degradation efficiency was attained not only by interfacial formation but also by the speedy transportation of electrons across the heterojunction. After 5 runs of the photocatalytic recylic process, the SRN photocatalyst exhibited ultimate stability without structural changes, and no noticeable degradation was observed. The outcomes of the ternary SRN nanocomposite manifest a dual photocatalytic scheme, the photocatalytic enrichment could be caused by the Z-scheme charge transfer process between GCN, SRT, and rGO nanocomposite, which helps effectual charge separation and keeps a high redox potential. From the results, SRN sample provides insight into the integration of an effective and potential photocatalyst for wastewater treatment toward real-time environmental remediation applications.

2.
Environ Res ; : 119626, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019143

RESUMO

The utilization of bio-oil derived from biomass presents a promising alternative to fossil fuels, though it faces challenges when directly applied in diesel engines. Microemulsification has emerged as a viable strategy to enhance bio-oil properties, facilitating its use in hybrid fuels. This study explores the microemulsification of Jatropha bio-oil with ethanol, aided by a surfactant, to formulate a hybrid liquid fuel. Additionally, a bio-nano CaO heterogeneous catalyst synthesized from eggshells is employed to catalyse the production of Jatropha biodiesel from the microemulsified fuel using microwave irradiation. The catalyst is characterized through UV-Vis, XRD, and SEM analysis. The investigation reveals a significant reduction in CO, CO2, and NOX emissions with the utilization of microemulsion-based biodiesel blends. Various blends of conventional diesel, Jatropha biodiesel, and ethanol are prepared with different ethanol concentrations (5, 10, and 20 wt%). Engine performance parameters, including fuel consumption, NOX emission, and brake specific fuel consumption, are analyzed. Results indicate that the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend exhibits superior performance compared to conventional diesel, Jatropha biodiesel, and other blends. The fuel consumption of the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend is measured at 554.6 g/h, surpassing that of conventional diesel and other biodiesel blends. The presence of water (0.14 %) in the blend reduces the heating value, consequently increasing the energy requirement. CO and CO2 emissions for the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend are notably lower compared to conventional C-18 hydrocarbons and various biodiesel blends. These findings accentuate the efficacy of the microemulsion process in enhancing fuel characteristics and reducing emissions. Further investigations could explore optimizing the emulsifying agents and their impact on engine performance and emission characteristics, contributing to the advancement of sustainable fuel technologies.

3.
Food Chem ; 459: 140348, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38991438

RESUMO

Three-dimensional printing is one of the emerging technologies that is gaining interest from the pharmaceutical industry as it provides an opportunity to customize drugs according to each patient's needs. Combining different active pharmaceutical ingredients, using different geometries, and providing sustained release enhances the effectiveness of medicine. One of the most innovative uses of 3D printing is producing fabrics, medical devices, medical implants, orthoses, and prostheses. This review summarizes the various 3D printing techniques such as stereolithography, inkjet printing, thermal inkjet printing, fused deposition modelling, extrusion printing, semi-solid extrusion printing, selective laser sintering, and hot-melt extrusion. Also, discusses the drug relies profile and its mechanisms, characteristics, and applications of the most common types of 3D printed API formulations and its recent development. Here, Authors also, summarizes the central flow of 3D food printing process and knowledge extension toward personalized nutrition.

4.
Environ Res ; : 119587, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992755

RESUMO

This study examines catalytic ability of various zeolite materials in converting discarded tire pyrolyzed oil by employing a moderate sized pyrolysis plant for a 10 L working volume. The yield of liquid fractions from γ-Al2O3 was greater than that of HZSM-5 and HY, whereas the least amount of condensates was formed when catalyst was not present. When enhanced tire waste pyrolysis oil was analyzed using Fourier transform infrared spectroscopy with an alumina catalyst, the stretching bands corresponding to aromatic and non-aromatic compounds were visible. The results of GC-MS examinations confirm this even more. The γ-Al2O3 catalyst yielded a higher amount of liquid oil than the other two catalysts. The cyclic unsaturated fragment percentages in liquids were decreased by the catalysts used to 53.9% with HY, 59.0% with γ-Al2O3, and 62.2% with HZSM-5, which produced aromatic chemicals. Nitrogen adsorption desorption analysis revealed that γ-Al2O3 has an enhanced surface area of 635 m2/g which improved its catalytic performance. The cracked liquid oil had viscosity (10.36 cSt), values of pour and flash temperatures of -2.2 °C and 41 °C respectively, analogous to petroleum diesel. The upgraded pyrolysis oil (10%) is blended with gasoline (90%) and emission analysis was performed. Moreover, liquid oil needs post treatment (refining) for its use as energy source in transportation application. The novelty of this research is in its comparative analysis of multiple catalysts under controlled conditions using a small pilot-scale pyrolysis reactor, which provides insights into optimizing the pyrolysis process for industrial applications.

5.
Environ Res ; 258: 119407, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38897435

RESUMO

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.

6.
Environ Res ; 258: 119474, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914253

RESUMO

In this study, we studied the conversion of Jatropha curcas oil to biodiesel by using three distinct reactor systems: microchannel, fixed bed, and microwave reactors. ZSM-5 was used as the catalyst for this conversion and was thoroughly characterized. X-ray diffraction was used to identify the crystalline structure, Brunauer-Emmett-Teller analysis to determine surface area, and temperature-programmed desorption to evaluate thermal stability and acidic properties. These characterizations provided crucial insights into the catalyst's structural integrity and performance under reaction conditions. The microchannel reactor exhibited superior biodiesel yield compared to the fixed bed and microwave reactors, and achieved peak efficiency at 60 °C, delivering high FAEE yield (99.7%) and conversion rates (99.92%). Ethanol catalyst volume at 1% was optimal, while varying flow rates exhibited trade-offs, emphasizing the need for nuanced control. Comparative studies against microwave and fixed-bed reactors consistently favored the microchannel reactor, emphasizing its remarkable FAME percentages, high conversion rates, and adaptability to diverse operating conditions. The zig-zag configuration enhances its efficiency, making it the optimal choice for biodiesel production and showcasing promising prospects for advancing sustainable biofuel synthesis technologies.

7.
Front Cell Infect Microbiol ; 14: 1414618, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903941

RESUMO

Candida species comprise a ubiquitous pathogenic fungal genus responsible for causing candidiasis. They are one of the primary causatives of several mucosal and systemic infections in humans and can survive in various environments. In this study, we investigated the antifungal, anti-biofilm, and anti-hyphal effects of six N-substituted phthalimides against three Candida species. Of the derivatives, N-butylphthalimide (NBP) was the most potent, with a minimum inhibitory concentration (MIC) of 100 µg/ml and which dose-dependently inhibited biofilm at sub-inhibitory concentrations (10-50 µg/ml) in both the fluconazole-resistant and fluconazole-sensitive Candida albicans and Candida parapsilosis. NBP also effectively inhibited biofilm formation in other pathogens including uropathogenic Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, and Vibrio parahaemolyticus, along with the polymicrobial biofilms of S. epidermidis and C. albicans. NBP markedly inhibited the hyphal formation and cell aggregation of C. albicans and altered its colony morphology in a dose-dependent manner. Gene expression analysis showed that NBP significantly downregulated the expression of important hyphal- and biofilm-associated genes, i.e., ECE1, HWP1, and UME6, upon treatment. NBP also exhibited mild toxicity at concentrations ranging from 2 to 20 µg/ml in a nematode model. Therefore, this study suggests that NBP has anti-biofilm and antifungal potential against various Candida strains.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Hifas , Testes de Sensibilidade Microbiana , Ftalimidas , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Antifúngicos/farmacologia , Ftalimidas/farmacologia , Candida albicans/efeitos dos fármacos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candidíase/microbiologia , Candidíase/tratamento farmacológico , Animais , Humanos , Candida parapsilosis/efeitos dos fármacos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fluconazol/farmacologia
8.
Environ Geochem Health ; 46(8): 261, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916678

RESUMO

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.


Assuntos
Cobalto , Compostos Férricos , Azul de Metileno , Níquel , Cobalto/química , Cobalto/análise , Níquel/química , Níquel/análise , Compostos Férricos/química , Azul de Metileno/química , Nanopartículas Metálicas/química , Gases , Catálise , Raios Ultravioleta , Recuperação e Remediação Ambiental/métodos , Nanopartículas/química , Óxido de Alumínio , Óxido de Magnésio
9.
Environ Geochem Health ; 46(7): 250, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877278

RESUMO

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.


Assuntos
Antibacterianos , Quitosana , Corantes , Nanocompostos , Prata , Poluentes Químicos da Água , Quitosana/química , Nanocompostos/química , Prata/química , Antibacterianos/farmacologia , Antibacterianos/química , Corantes/química , Poluentes Químicos da Água/química , Catálise , Vermelho Congo/química , Recuperação e Remediação Ambiental/métodos , Águas Residuárias/química , Luz
10.
ACS Appl Mater Interfaces ; 16(22): 29374-29389, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38781311

RESUMO

In this work, new strategies were developed to prepare 1D-V2MoO8 (VMO) rods from 2D V-doped MoSe2 nanosheets (VMoSe2) with good control over morphology and crystallinity by a facile hydrothermal and calcination process. The morphological changes from 2D to 1D rods were controlled by changing the calcination temperature from 300 to 600 °C. The elimination of Se and the incorporation of O into the V-Mo structure were evaluated by TGA, p-XRD, Raman, FE-SEM, EDAX, FE-TEM, and XPS analyses. These results prove that the optimization of the physical parameters leads to changes in the crystal phase and textural properties of the prepared material. The VMoSe2 and its calcined products were investigated as electrochemical sensors for the detection of the antibacterial drug nitrofurantoin (NFT). At a calcination temperature of 500 °C, the modified screen-printed carbon electrodes (SPCE) proved to be an excellent electrochemical sensor for the detection of NFT in neutral media. Under the optimized conditions, VMO-500 °C/SPCE exhibits low detection limit (LOD) (0.015 µM), wide linear ranges (0.1-31, 47-1802 µM), good sensitivity, and selectivity. The proposed sensor was successfully used for the analysis of NFT in real samples with good recovery results. Moreover, the reduction potential of NFT agreed well with the theoretical analysis using quantum chemical calculations, with the B3LYP with 6-31G(d,p) basis set predicting an E0 value of -0.45 V. The interaction between the electrode surface and NFT via the LUMO diagram and the electrostatic potential surface is also discussed.

11.
Front Cell Infect Microbiol ; 14: 1404960, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803574

RESUMO

Staphylococcus aureus and Staphylococcus epidermidis stand as notorious threats to human beings owing to the myriad of infections they cause. The bacteria readily form biofilms that help in withstanding the effects of antibiotics and the immune system. Intending to combat the biofilm formation and reduce the virulence of the pathogens, we investigated the effects of carotenoids, crocetin, and crocin, on four Staphylococcal strains. Crocetin was found to be the most effective as it diminished the biofilm formation of S. aureus ATCC 6538 significantly at 50 µg/mL without exhibiting bactericidal effect (MIC >800 µg/mL) and also inhibited the formation of biofilm by MSSA 25923 and S. epidermidis at a concentration as low as 2 µg/mL, and that by methicillin-resistant S. aureus MW2 at 100 µg/mL. It displayed minimal to no antibiofilm efficacy on the Gram-negative strains Escherichia coli O157:H7 and Pseudomonas aeruginosa as well as a fungal strain of Candida albicans. It could also curb the formation of fibrils, which partly contributes to the biofilm formation in S. epidermidis. Additionally, the ADME analysis of crocetin proclaims how relatively non-toxic the chemical is. Also, crocetin displayed synergistic antibiofilm characteristics in combination with tobramycin. The presence of a polyene chain with carboxylic acid groups at its ends is hypothesized to contribute to the strong antibiofilm characteristics of crocetin. These findings suggest that using apocarotenoids, particularly crocetin might help curb the biofilm formation by S. aureus and S. epidermidis.


Assuntos
Antibacterianos , Biofilmes , Carotenoides , Testes de Sensibilidade Microbiana , Staphylococcus epidermidis , Vitamina A , Biofilmes/efeitos dos fármacos , Carotenoides/farmacologia , Vitamina A/análogos & derivados , Vitamina A/farmacologia , Antibacterianos/farmacologia , Staphylococcus epidermidis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos
12.
Sci Rep ; 14(1): 9160, 2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38644387

RESUMO

Food-related illnesses have become a growing public concern due to their considerable socioeconomic and medical impacts. Vibrio parahaemolyticus and Staphylococcus aureus have been implicated as causative organisms of food-related infections and poisoning, and both can form biofilms which confer antibiotic resistance. Hence, the need for continuous search for compounds with antibiofilm and antivirulence properties. In this study, 22 iodinated hydrocarbons were screened for their antibiofilm activity, and of these, iodopropynyl butylcarbamate (IPBC) was found to effectively control biofilm formation of both pathogens with a MIC of 50 µg/mL which was bactericidal to V. parahaemolyticus and S. aureus. Microscopic studies confirmed IPBC inhibits biofilm formation of both bacteria and also disrupted their mixed biofilm formation. Furthermore, IPBC suppressed virulence activities such as motility and hemolytic activity of V. parahaemolyticus and the cell surface hydrophobicity of S. aureus. It exhibited a preservative potential against both pathogens in a shrimp model. IPBC disrupted the cell membrane of S. aureus and V. parahaemolyticus and differentially affected gene expressions related to biofilm formation and virulence. Additionally, it displayed broad-spectrum antibiofilm activities against other clinically relevant pathogens. These findings indicate IPBC offers a potential means of controlling infections mediated by Vibrio and Staphylococcus biofilms.


Assuntos
Antibacterianos , Biofilmes , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Vibrio parahaemolyticus , Biofilmes/efeitos dos fármacos , Vibrio parahaemolyticus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Antibacterianos/farmacologia , Antibacterianos/química , Animais , Virulência/efeitos dos fármacos
13.
Materials (Basel) ; 17(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38673251

RESUMO

Novel flake-like Ni1-xSnxO2 particles were successfully prepared by template-free hydrothermal synthesis. The prepared samples were investigated for their properties by different characterization techniques. Scanning micrographs showed that the obtained particles consisted of nanoflakes. The X-ray diffraction results of the Ni1-xSnxO2 revealed the formation of mixed-phase Ni/SnO2 having the typical tetragonal structure of SnO2, and the cubic structure of Ni in a nanocrystalline nature. The doping with Ni had a certain influence on the host's lattice structure of SnO2 at different doping concentrations. Confirmation of the functional groups and the elements in the nanomaterials was accomplished using FTIR and EDS analyses. The electrochemical performance analysis of the prepared nanomaterials were carried out with the help of the CV, GCD, and EIS techniques. The specific capacitance of the synthesized nanomaterials with different concentrations of Ni dopant in SnO2 was analyzed at different scanning rates. Interestingly, a 5% Ni-doped SnO2 nanocomposite exhibited a maximum specific capacitance of 841.85 F g-1 at 5 mV s-1 in a 6 M KOH electrolyte. Further, to boost the electrochemical performance, a redox additive electrolyte was utilized, which exhibited a maximum specific capacitance of 2130.33 at 5 mV s-1 and an excellent capacitance retention of 93.22% after 10,000 GCD cycles. These excellent electrochemical characteristics suggest that the Ni/SnO2 nanocomposite could be utilized as an electrode material for high-performance supercapacitors.

14.
Front Cell Infect Microbiol ; 14: 1340910, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606300

RESUMO

Vibrios are associated with live seafood because they are part of the indigenous marine microflora. In Asia, foodborne infections caused by Vibrio spp. are common. In recent years, V. parahaemolyticus has become the leading cause of all reported food poisoning outbreaks. Therefore, the halogenated acid and its 33 derivatives were investigated for their antibacterial efficacy against V. parahaemolyticus. The compounds 3,5-diiodo-2-methoxyphenylboronic acid (DIMPBA) and 2-fluoro-5-iodophenylboronic acid (FIPBA) exhibited antibacterial and antibiofilm activity. DIMPBA and FIPBA had minimum inhibitory concentrations of 100 µg/mL for the planktonic cell growth and prevented biofilm formation in a dose-dependent manner. Both iodo-boric acids could diminish the several virulence factors influencing the motility, agglutination of fimbria, hydrophobicity, and indole synthesis. Consequently, these two active halogenated acids hampered the proliferation of the planktonic and biofilm cells. Moreover, these compounds have the potential to effectively inhibit the presence of biofilm formation on the surface of both squid and shrimp models.


Assuntos
Ácidos Borônicos , Vibrio parahaemolyticus , Vibrio , Biofilmes , Fatores de Virulência/farmacologia , Antibacterianos/farmacologia
15.
Bioresour Technol ; 400: 130665, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582235

RESUMO

Biogas production through anaerobic digestion (AD) is one of the complex non-linear biological processes, wherein understanding its dynamics plays a crucial role towards process control and optimization. In this work, a machine learning based biogas predictive model was developed for high solid systems using algorithms, including SVM, ET, DT, GPR, and KNN and two different datasets (Dataset-1:10, Dataset-2:5 inputs). Support Vector Machine had the highest accuracy (R2) of all the algorithms at 91 % (Dataset-1) and 87 % (Dataset-2), respectively. The statistical analysis showed that there was no significant difference (p = 0.377) across the datasets, wherein with less inputs, accurate results could be predicted. In case of biogas yield, the critical factors which affect the model predictions include loading rate and retention time. The developed high solid machine learning model shows the possibility of integrating Artificial Intelligence to optimize and control AD process, thus contributing to a generic model for enhancing the overall performance of the biogas plant.


Assuntos
Biocombustíveis , Aprendizado de Máquina , Anaerobiose , Máquina de Vetores de Suporte , Algoritmos , Reatores Biológicos
16.
Artigo em Inglês | MEDLINE | ID: mdl-38653896

RESUMO

The modern world requires a chemical industry that can run at low production costs while producing high-quality products with minimal environmental impact. The development of environmentally friendly, cost-effective, and efficient wastewater treatment materials remains a major problem for the sustainable approach. We prepared nanoscale cadmium sulfide (CdS)-enwrapped polypyrrole (PPy) polymer composites for degradation of organic pollutants. The prepared CdS@PPy nanocomposites were characterized by powder X-ray diffraction, scanning electron microscope (SEM), field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet-visible (UV) absorption spectroscopy, indicating proper intercalation between CdS and PPy. Consequently, the catalytic efficiency of the synthesized hybrid nanocomposites was analyzed through the degradation of methylene blue (MB) and rhodamine B (Rh B) under visible light irradiation. The measured degradation efficiency of the dye solutions under the photolysis process is about 18% and 23% for MB and Rh B dye, respectively. Furthermore, the recycle test result concludes that the CdS@PPy composite exhibits 91% and 89% of MB and Rh B dye degradation efficiency even at the 4th cycle, respectively. The positive synergistic impact of CdS and PPy may be the result of effective photocatalytic degradation of MB and RhB.

17.
Chemosphere ; 355: 141790, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554870

RESUMO

Cadmium sulfide-tin sulfide (CdS-SnS) nanoparticles are a novel kind of photocatalyst. These CdS-SnS nanoparticles are synthesized and characterized using UV-Vis, FT-IR, XRD, SEM-EDX, and DLS techniques, to understand their size distribution, crystalline nature, morphology, shape, optical properties, and elemental composition. This research offers insight into the efficient photocatalytic degradation of Phenanthrene (PHE) using CdS-SnS. The CdS-SnS NPs as photocatalyst can effectively photodegrade the polycyclic aromatic hydrocarbons (PAH) such as phenanthrene under simulated solar and UV light. UV-vis spectra of these nanoparticles exhibit peaks at 365 and 546 cm-1 respectively, the mean size of the CdS-SnS NPs in DLS is determined to be 78 nm. The CdS-SnS stretching frequency was observed at wave numbers below 700 cm-1, the absorption peak at 1123 cm-1 indicates the presence of C-N stretch or CS bond of thiourea, while the peak at 1350.38 cm-1 corresponds to the tris-amine C-N stretch in FT-IR. Additionally, the peaks observed at 2026 cm-1 indicate the presence of isothiocyanate (NCS). 1456.23 cm-1 represents the asymmetric scissor deformation vibration. EDAX revealed the presence of elemental Cd and Sn oxides. The antimicrobial studies showed that the CdS-SnS NPs at the concentration of 150 µg/mL, exhibit maximum inhibition (15 ± 1.25 mm) against the strains Proteus mirabilis followed by Staphylococcus epidermidis and Clostridium spp. Among fungal strains Colletotrichum spp. exhibits the maximum zone of inhibition (9 ± 0.25). This research also observed the cytotoxic effects of CdS-SnS NPs on HepG2 and ZF4 cells. HepG2 cells exhibited 50% inhibition at 50 µg/mL and 70% inhibition at 100 µg/mL concentrations, while ZF4 cells exhibited 50% inhibition at 50 µg/mL and 78% inhibition at 100 µg/mL concentrations, respectively. The parameters like concentration of PHE, concentration of CdS-SnS NPs, pH, and sources of irradiation on batch adsorption were examined to maximize the efficiency of the photodegradation process.


Assuntos
Compostos de Cádmio , Nanopartículas , Fenantrenos , Sulfetos , Luz , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Fenantrenos/toxicidade
18.
Chemosphere ; 352: 141352, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307332

RESUMO

Benzopyrene (BaP) stands as a potent polycyclic aromatic hydrocarbon (PAH) molecule, boasting five fused aromatic rings, making its way into the human food chain through soil contamination. The persistent environmental presence of PAHs in soil, attributed to industrial exposure, is primarily due to their low molecular weight and hydrophobic nature. To preemptively address the entry of BaP into the food chain, the application of nanocomposites was identified as an effective remediation strategy. Post-synthesis, comprehensive characterization tests employing techniques such as UV-DRS, XRD, SEM-EDX, FTIR, and DLS unveiled the distinctive features of the g-C3N4-SnS nanocomposites. These nanocomposites exhibited spherical shapes embedded on layers of nanosheets, boasting particle diameters measuring 88.9 nm. Subsequent tests were conducted to assess the efficacy of eliminating benzopyrene from a combination of PAH molecules and g-C3N4-SnS nanocomposites. Varied parameters, including PAH concentration, adsorbent dosage, and suspension pH, were systematically explored. The optimized conditions for the efficient removal of BaP utilizing the g-C3N4-SnS nanocomposite involved 2 µg/mL of benzopyrene, 10 µg/mL of the nanocomposite, and a pH of 5, considering UV light as the irradiation source. The investigation into the mechanism governing BaP elimination closely aligned with batch adsorption results involved a thorough exploration of adsorption kinetics and isotherms. Photocatalytic degradation of benzopyrene was achieved, reaching a maximum of 86 % in 4 h and 36 % in 2 h, with g-C3N4-SnS nanocomposite acting as the catalyst. Further validation through HPLC data confirmed the successful removal of BaP from the soil matrix.


Assuntos
Grafite , Nanocompostos , Compostos de Nitrogênio , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Nanocompostos/química , Grafite/química , Benzo(a)pireno , Benzopirenos , Solo , Catálise
19.
Environ Res ; 252(Pt 1): 118454, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387488

RESUMO

The oncogenic and genetic properties of anthracene, a member of the polycyclic aromatic hydrocarbons (PAHs) family, pose a significant health threat to humans. This study aims to investigate the photocatalytic decomposition of anthracene under various conditions, such as different concentrations of PAHs, varying amounts of NiO (nickel oxide) nanoparticles, and different pH levels under ultraviolet light and sunlight. The synthesized NiO nanoparticles showed surface plasma resonance at 230 and 360 nm, while XRD and SEM analysis confirmed the nanoparticles were cubic crystalline in structure with sizes ranging between 37 and 126 nm. NiO nanoparticles exhibited 79% degradation of pyrene at 2 µg/mL of anthracene within 60 min of treatment. NiO at 10 µg/mL concentration showed significant adsorption of 57%, while the adsorption method worked efficiently (72%) at 5 pH. Photocatalytic degradation was confirmed by isotherm and kinetic studies through monolayer adsorption and pseudo-first-order kinetics. Further, the absorption process was confirmed by performing GC-MS analysis of the NiO nanoparticles. On the other hand, NiO nanoparticles showed antimicrobial activity against Gram negative and Gram-positive bacteria. Therefore, the present work is one of its kind proving the dual application of NiO nanoparticles, which makes them suitable candidates for bioremediation by treating PAHs and killing pathogenic bacteria.


Assuntos
Níquel , Hidrocarbonetos Policíclicos Aromáticos , Níquel/química , Hidrocarbonetos Policíclicos Aromáticos/química , Nanopartículas Metálicas/química , Catálise , Fotólise , Raios Ultravioleta , Nanopartículas/química , Concentração de Íons de Hidrogênio , Antracenos/química , Adsorção
20.
Environ Geochem Health ; 46(3): 96, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376605

RESUMO

SrTiO3/Ag nanocomposites were synthesized using a facile wet impregnation method, employing rigorous experimental techniques for comprehensive characterization. XRD, FTIR, UV, PL, FESEM, and HRTEM were meticulously utilized to elucidate their structural, functional, morphological, and optical properties. The electrochemical performance of the SrTiO3/Ag nanocomposite was rigorously assessed, revealing an impressive specific capacitance of 850 F/g at a current density of 1 A. Furthermore, the photocatalytic activity of the SrTiO3/Ag nanocomposite was rigorously examined using methylene blue (MB) dye, and the results were outstanding. After 120 min of UV irradiation, the nanocomposite exhibited an exceptional MB dye degradation efficiency exceeding 88%. The SrTiO3/Ag nanocomposite represents an exemplary catalyst in terms of efficiency, cost-effectiveness, environmental compatibility, and reusability. The electron and superoxide radicals play a chief role in the MB dye degradation process. The inclusion of Ag within the SrTiO3 matrix facilitated the formation of a conductive nano-network, ultimately resulting in superior capacitive and photocatalytic performance.


Assuntos
Poluentes Ambientais , Nanopartículas , Prata , Condutividade Elétrica , Azul de Metileno
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