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1.
Environ Res ; 259: 119435, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38914255

RESUMO

Herein, the study introduces a novel bifunctional In2S3/MgTiO3/TiO2@N-CNT (IMTNC) nanocomposite, which is poised to revolutionize the detection and removal of clothianidin (CLD) from aquatic environments by synergistic adsorption and photodegradation. Confirmation of the material's synthesis was done using structural, optical, morphological, and chemical characterizations. An outstanding sensitivity of 2.168 µA/nM.cm2 with a linear range of 4-100 nM and a LOD of 0.04 nM, along with an exceptional elimination efficiency of 98.06 ± 0.84% for about 10 ppm CLD within 18 min was demonstrated by the IMTNC nanocomposite. Extensive studies were carried out to appraise the material's effectiveness in the presence of various interfering species, such as cations, anions, organic compounds, and different water matrices, and a comprehensive assessment of its stability throughout several cycles was made. Response Surface Methodology (RSM) study was used to determine the ideal removal conditions for improved performance. In addition, the catalytic performance in removing various other pollutants was also analyzed. Adding In2S3 and developing N-doped Carbon Nanotubes (N-CNT) increased conductivity and higher electrochemical sensing skills, improving charge transfer and increasing photocatalytic activity. This research underscores the potential of the IMTNC nanocomposite as a promising candidate for advanced environmental sensing and remediation applications.


Assuntos
Guanidinas , Inseticidas , Nanotubos de Carbono , Neonicotinoides , Tiazóis , Titânio , Poluentes Químicos da Água , Guanidinas/química , Guanidinas/análise , Neonicotinoides/química , Neonicotinoides/análise , Tiazóis/química , Tiazóis/análise , Inseticidas/química , Inseticidas/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Titânio/química , Nanotubos de Carbono/química , Nitrogênio/química , Nanocompostos/química , Adsorção
2.
J Environ Manage ; 366: 121802, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39003907

RESUMO

This study proposes a novel one-pot hydrothermal impregnation strategy for surface decoration of waste derived pisum sativum biochar with zero‒dimensional Cu‒MOF Quantum dots (PBC‒HK), with an average particle size of 5.67 nm, for synergistic removal of an emerging sulfur containing drug pantoprazole (PTZ) and Basic Blue 26 (VB) dye within 80 min and 50 min of visible-light exposure, respectively. The designed Integrated Photocatalytic Adsorbent (IPA) presented an enhanced PTZ removal efficiency of 95.23% with a catalyst loading of 0.24 g/L and initial PTZ conc. 30 mg/L at pH 7, within 80 min via synergistic adsorption and photodegradation under visible-light exposure. While, on the other hand, 96.31% VB removal efficiency was obtained in 50 min with a catalyst dosage of 0.20 g/L, initial VB conc. 60 mg/L at pH 7 under similar irradiation conditions. An in-depth analysis of the synergistic adsorption and photocatalysis mechanism resulting in the shortened time for the removal of contaminants in the synergistic integrated model has been performed by outlining the various advantageous attributes of this strategy. The first-order degradation rate constant for PTZ was found to be 0.04846 min-1 and 0.04370 min-1 for PTZ and VB, respectively. Adsorption of contaminant molecules on the biochar (PS‒BC) surface can facilitate photodegradation by accelerating the kinetics, and photodegradation promotes regeneration of adsorption sites, contributing to an overall reduction in operation time for removal of contaminants. Besides enhancing the adsorption of targeted pollutants, the carbon matrix of IPAs serves as a surface for adsorption of intermediates of degradation, thereby minimizing the risk of secondary pollution. The photogenerated holes present in the VB is responsible for the generation of •OH radicals. While, the photogenerated electrons present in the CB are captured by Cu2+ of the MOF metal center, reducing it to Cu+, which is subsequently oxidized to produce additional •OH species in the aqueous medium. This process leads to effective charge separation of the photogenerated charge carriers and minimizes the probability of charge recombination as evident from photoluminescence (PL) analysis. Meanwhile, PL studies, EPR and radical trapping experiments indicate the predominant role of •OH radicals in the removal mechanism of PTZ and VB. The investigation of the degradation reaction intermediates was confirmed by HR‒LCMS, on the basis of which the plausible degradation pathway was elucidated in detail. Moreover, effects of pH, inorganic salts, other organic compounds and humic acid concentration have been investigated in detail. The environmental impact of the proposed method was comprehensively evaluated by ICP-OES analysis and TOC and COD removal studies. Furthermore, the economic feasibility and the cost-effectiveness of the catalyst was assessed to address the potential for large scale commercialization. Notably, this research not only demonstrates a rational design strategy for the utilization of solid waste into treasure via the fabrication of IPAs based on MOF Quantum dots (QDs) and waste-derived biochar, but also provides a practical solution for real wastewater treatment systems for broader industrial applications.


Assuntos
Carvão Vegetal , Cobre , Estruturas Metalorgânicas , Pontos Quânticos , Pontos Quânticos/química , Carvão Vegetal/química , Adsorção , Estruturas Metalorgânicas/química , Cobre/química , Poluentes Químicos da Água/química
3.
Semin Cancer Biol ; 80: 205-217, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-32450139

RESUMO

Autophagy is an intracellular catabolic self-cannibalism that eliminates dysfunctional cytoplasmic cargos by the fusion of cargo-containing autophagosomes with lysosomes to maintain cyto-homeostasis. Autophagy sustains a dynamic interlink between cytoprotective and cytostatic function during malignant transformation in a context-dependent manner. The antioxidant and immunomodulatory phyto-products govern autophagy and autophagy-associated signaling pathways to combat cellular incompetence during malignant transformation. Moreover, in a close cellular signaling circuit, autophagy regulates aberrant epigenetic modulation and inflammation, which limits tumor metastasis. Thus, manipulating autophagy for induction of cell death and associated regulatory phenomena will embark on a new strategy for tumor suppression with wide therapeutic implications. Despite the prodigious availability of lead pharmacophores in nature, the central autophagy regulating entities, their explicit target, as well as pre-clinical and clinical assessment remains a major question to be answered. In addition to this, the stage-specific regulation of autophagy and mode of action with natural products in regulating the key autophagic molecules, control of tumor-specific pathways in relation to modulation of autophagic network specify therapeutic target in caner. Moreover, the molecular pathway specificity and enhanced efficacy of the pre-existing chemotherapeutic agents in co-treatment with these phytochemicals hold high prevalence for target specific cancer therapeutics. Hence, the multi-specific role of phytochemicals in a cellular and tumor context dependent manner raises immense curiosity for investigating of novel therapeutic avenues. In this perspective, this review discusses about diverse implicit mechanisms deployed by the bioactive compounds in diagnosis and therapeutics approach during cancer progression with special insight into autophagic regulation.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Autofagia , Transformação Celular Neoplásica/metabolismo , Humanos , Lisossomos/patologia , Neoplasias/patologia , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico
4.
Semin Cancer Biol ; 83: 399-412, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33039557

RESUMO

Tumour-promoting inflammation is a critical hallmark in cancer development, and inflammasomes are well-known regulators of inflammatory processes within the tumour microenvironment. Different inflammasome components along with the adaptor, apoptosis-associated speck-like protein containing caspase activation and recruitment domain (ASC), and the effector, caspase-1, have a significant influence on tumorigenesis but in a tissue-specific and stage-dependent manner. The downstream products of inflammasome activation, that is the proinflammatory cytokines such as IL-1ß and IL-18, regulate tissue homeostasis and induce antitumour immune responses, but in contrast, they can also favour cancer growth and proliferation by directing various oncogenic signalling pathways in cancer cells. Moreover, different epigenetic mechanisms, including DNA methylation, histone modification and noncoding RNAs, control inflammasomes and their components by regulating gene expression during cancer progression. Furthermore, autophagy, a master controller of cellular homeostasis, targets inflammasome-induced carcinogenesis by maintaining cellular homeostasis and removing potential cancer risk factors that promote inflammasome activation in support of tumorigenesis. Here, in this review, we summarize the effect of inflammasome activation in cancers and discuss the role of epigenetic and autophagic regulatory mechanisms in controlling inflammasomes. A proper understanding of the interactions among these key processes will be useful for developing novel therapeutic regimens for targeting inflammasomes in cancer.


Assuntos
Inflamassomos , Neoplasias , Autofagia/genética , Carcinogênese/genética , Epigênese Genética , Humanos , Inflamassomos/genética , Inflamassomos/metabolismo , Neoplasias/genética , Microambiente Tumoral/genética
5.
J Environ Manage ; 334: 117496, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36801688

RESUMO

This study aims to fabricate a novel integrated photocatalytic adsorbent (IPA) via a green solvothermal process employing tea (Camellia sinensis var. assamica) leaf extract as a stabilizing and capping agent for the removal of organic pollutants from wastewater. An n-type semiconductor photocatalyst, SnS2, was chosen as a photocatalyst due to its remarkable photocatalytic activity supported over areca nut (Areca catechu) biochar for the adsorption of pollutants. The adsorption and photocatalytic properties of fabricated IPA were examined by taking amoxicillin (AM) and congo red (CR) as two emerging pollutants found in wastewater. Investigating synergistic adsorption and photocatalytic properties under varying reaction conditions mimicking actual wastewater conditions marks the novelty of the present research. The support of biochar for the SnS2 thin films induced a reduction in charge recombination rate, which enhanced the photocatalytic activity of the material. The adsorption data were in accordance with the Langmuir nonlinear isotherm model, indicating monolayer chemosorption with the pseudo-second-order rate kinetics. The photodegradation process follows pseudo-first-order kinetics with the highest rate constant of 0.0450 min-1 for AM and 0.0454 min-1 for CR. The overall removal efficiency of 93.72 ± 1.19% and 98.43 ± 1.53% could be achieved within 90 min for AM and CR via simultaneous adsorption and photodegradation model. A plausible mechanism of synergistic adsorption and photodegradation of pollutants is also presented. The effect of pH, Humic acid (HA) concentration, inorganic salts and water matrices have also been included.The photodegradation activity of SnS2 under visible light coupled with the adsorption capability of the biochar results in the excellent removal of the contaminants from the liquid phase.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Amoxicilina , Vermelho Congo , Água/química , Adsorção , Fotólise , Águas Residuárias , Carvão Vegetal/química , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
6.
Cell Mol Life Sci ; 78(23): 7435-7449, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34716768

RESUMO

Lysosomes are single membrane-bound organelles containing acid hydrolases responsible for the degradation of cellular cargo and maintenance of cellular homeostasis. Lysosomes could originate from pre-existing endolysosomes or autolysosomes, acting as a critical juncture between autophagy and endocytosis. Stress that triggers lysosomal membrane permeabilization can be altered by ESCRT complexes; however, irreparable damage to the membrane results in the induction of a selective lysosomal degradation pathway, specifically lysophagy. Lysosomes play an indispensable role in different types of autophagy, including microautophagy, macroautophagy, and chaperone-mediated autophagy, and various cell death pathways such as lysosomal cell death, apoptotic cell death, and autophagic cell death. In this review, we discuss lysosomal reformation, maintenance, and degradation pathways following the involvement of the lysosome in autophagy and cell death, which are related to several pathophysiological conditions observed in humans.


Assuntos
Apoptose/imunologia , Autofagia/imunologia , Endocitose/imunologia , Lisossomos/imunologia , Envelhecimento/patologia , Animais , Membrana Celular/metabolismo , Humanos , Membranas Intracelulares/metabolismo
7.
Semin Cancer Biol ; 66: 45-58, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31351198

RESUMO

Mitophagy is an evolutionarily conserved cellular process which selectively eliminates dysfunctional mitochondria by targeting them to the autophagosome for degradation. Dysregulated mitophagy results in the accumulation of damaged mitochondria, which plays an important role in carcinogenesis and tumor progression. The role of mitophagy receptors and adaptors including PINK1, Parkin, BNIP3, BNIP3L/NIX, and p62/SQSTM1, and the signaling pathways that govern mitophagy are impaired in cancer. Furthermore, the contribution of mitophagy in regulating the metabolic switch may establish a balance between aerobic glycolysis and oxidative phosphorylation for cancer cell survival. Moreover, ROS-driven mitophagy achieves different goals depending on the stage of tumorigenesis. Mitophagy promotes plasticity in the cancer stem cell through the metabolic reconfiguration for better adaption to the tumor microenvironment. In addition, the present review sheds some light on the role of mitophagy in stemness and differentiation during the transition of cell's fate, which could have a crucial role in cancer progression and metastasis. In conclusion, this review deals with the detailed molecular mechanisms underlying mitophagy, along with highlighting the dual role of mitophagy in different aspects of cancer, suggesting it as a possible target in the mitophagy-modulated cancer therapy.


Assuntos
Mitofagia/fisiologia , Neoplasias/patologia , Animais , Diferenciação Celular/fisiologia , Humanos , Mitocôndrias/patologia , Células-Tronco Neoplásicas/patologia , Transdução de Sinais/fisiologia
8.
Semin Cancer Biol ; 66: 22-33, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31158463

RESUMO

Epigenetic alterations, such as DNA methylation, histone modifications and miRNAs, have a significant role play in malignant cellular transformation and metastasis. On the other hand, autophagy has been reported to perform context-dependent roles in cancer; at times, it becomes lethal and abolishes tumorigenesis, whereas, at other instances, it protects cancer cells by providing a rescue mechanism under adverse conditions. Although epigenetics and autophagy are two important and independent cellular processes, various oncogenic and oncosuppressor proteins involve autophagy through epigenetic modifications and different signaling pathways, thereby regulating tumor growth and therapeutic response. Moreover, the importance of epigenetic modification of autophagy in cancer is reflected through its involvement in cancer stem cell maintenance, which in turn, contributes to tumor cell viability during dormancy leading to tumor recurrence. The effects of epigenetic modifications of autophagy in cancer is still ambiguous and less acknowledged; therefore, efforts have been made to understand its detail underlying mechanism to unveil new targets and avenues for better prognosis and diagnosis of cancer.


Assuntos
Autofagia/genética , Epigênese Genética/genética , Neoplasias/genética , Animais , Sobrevivência Celular/genética , Histonas/genética , Humanos , MicroRNAs/genética , Prognóstico , Transdução de Sinais/genética
9.
Biopolymers ; 112(10): e23471, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34498740

RESUMO

Extant fold-switching proteins remodel their secondary structures and change their functions in response to cellular stimuli, regulating biological processes and affecting human health. Despite their biological importance, these proteins remain understudied. Predictive methods are needed to expedite the process of discovering and characterizing more of these shapeshifting proteins. Most previous approaches require a solved structure or all-atom simulations, greatly constraining their use. Here, we propose a high-throughput sequence-based method for predicting extant fold switchers that transition from α-helix in one conformation to ß-strand in the other. This method leverages two previous observations: (a) α-helix â†” ß-strand prediction discrepancies from JPred4 are a robust predictor of fold switching, and (b) the fold-switching regions (FSRs) of some extant fold switchers have different secondary structure propensities when expressed by themselves (isolated FSRs) than when expressed within the context of their parent protein (contextualized FSRs). Combining these two observations, we ran JPred4 on 99-fold-switching proteins and found strong correspondence between predicted and experimentally observed α-helix â†” ß-strand discrepancies. To test the overall robustness of this finding, we randomly selected regions of proteins not expected to switch folds (single-fold proteins) and found significantly fewer predicted α-helix â†” ß-strand discrepancies. Combining these discrepancies with the overall percentage of predicted secondary structure, we developed a classifier to identify extant fold switchers (Matthews correlation coefficient of .71). Although this classifier had a high false-negative rate (7/17), its false-positive rate was very low (2/136), suggesting that it can be used to predict a subset of extant fold switchers from a multitude of available genomic sequences.


Assuntos
Dobramento de Proteína , Proteínas , Humanos , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Estrutura Secundária de Proteína
10.
Environ Res ; 197: 111077, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33794171

RESUMO

Herein, a novel synthetic strategy has been proposed to prepare engineered SnO2@ZIF-8/gC3N4 nanohybrids for electrochemical sensing of p-nitrophenol (p-NP). The electrochemical properties were investigated using cyclic voltammetry (CV), chronoamperometry (CA), and differential pulse voltammetry (DPV). The developed nanohybrid sensor displayed an excellent electrochemical performance towards sensing of p-NP with a detection limit of 0.565 µM. The sensitivity of the prepared nanohybrid was found to be 2.63 µAcm-2µM-1. Moreover, the newly fabricated sensor exhibited remarkable selectivity (over tenfold excess) in the presence of common interferents. The simultaneous detection of isomers of nitrophenol is difficult using the developed sensor. However, other common interferents, such as phenol and aminophenol have negligible effects on the sensitivity of SnO2@ZIF-8/gC3N4 towards the detection of p-nitrophenol. Further, the newly developed sensor showed consistency of sensing response up to 30 days. Thus, implementation of SnO2@ZIF-8/gC3N4 nanohybrids as a p-NP electrochemical sensor offers the advantages of simplicity, selectivity, and stability.


Assuntos
Técnicas Eletroquímicas , Nitrofenóis , Limite de Detecção
11.
Pattern Recognit ; 117: 107999, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33967346

RESUMO

The early detection of COVID-19 is a challenging task due to its deadly spreading nature and existing fear in minds of people. Speech-based detection can be one of the safest tools for this purpose as the voice of the suspected can be easily recorded. The Mel Frequency Cepstral Coefficient (MFCC) analysis of speech signal is one of the oldest but potential analysis tools. The performance of this analysis mainly depends on the use of conversion between normal frequency scale to perceptual frequency scale and the frequency range of the filters used. Traditionally, in speech recognition, these values are fixed. But the characteristics of speech signals vary from disease to disease. In the case of detection of COVID-19, mainly the coughing sounds are used whose bandwidth and properties are quite different from the complete speech signal. By exploiting these properties the efficiency of the COVID-19 detection can be improved. To achieve this objective the frequency range and the conversion scale of frequencies have been suitably optimized. Further to enhance the accuracy of detection performance, speech enhancement has been carried out before extraction of features. By implementing these two concepts a new feature called COVID-19 Coefficient (C-19CC) is developed in this paper. Finally, the performance of these features has been compared.

12.
Mol Biol Rep ; 47(9): 7209-7228, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32797349

RESUMO

Marine invertebrates are extremely diverse, largely productive, untapped oceanic resources with chemically unique bioactive lead compound contributing a wide range of screening for the discovery of anticancer compounds. The lead compounds have unfurled an extensive array of pharmacological properties owing to the presence of polyphenols, alkaloids, terpenoids and other secondary metabolites. The antioxidant, immunomodulatory and anti-tumor activities exhibited, are possibly regulated by the apoptosis induction, scavenging of ROS and modulation of cellular signaling pathways to defy the cellular deafness during carcinogenesis. Despite the enriched bioactive compounds, the marine invertebrates are largely unexplored as identification, screening, pre-clinical and clinical assessment of lead compounds and their synthetic analogs remain a major task to be solved. In the current review, we focus on the principle strategy and underlying mechanisms deployed by the bioactive anticancer compounds derived from marine invertebrates to combat cancer with special insight into the cell death mechanism.


Assuntos
Antineoplásicos , Organismos Aquáticos/química , Invertebrados/química , Neoplasias , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia
13.
Cell Mol Life Sci ; 76(17): 3263-3282, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30982077

RESUMO

Dysregulation of the epigenome and constitutional epimutation lead to aberrant expression of the genes, which regulate cancer initiation and progression. Histone deacetylases (HDACs), which are highly conserved in yeast to humans, are known to regulate numerous proteins involved in the transcriptional regulation of chromatin structures, apoptosis, autophagy, and mitophagy. In addition, a non-permissive chromatin conformation is created by HDACs, preventing the transcription of the genes encoding the proteins associated with tumorigenesis. Recently, an expanding perspective has been reported from the clinical trials with HDACis (HDAC inhibitors), which has emerged as a determining target for the study of the detailed mechanisms underlying cancer progression. Therefore, the present review focuses on the comprehensive lucubration of post-translational modifications and the molecular mechanisms through which HDACs alter the ambiguities associated with epigenome, with particular insights into the initiation, progression, and regulation of cancer.


Assuntos
Apoptose , Autofagia , Histona Desacetilases/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Epigenômica , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/química , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Processamento de Proteína Pós-Traducional
14.
Pharmacol Res ; 144: 8-18, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30951812

RESUMO

Plant lectins are non-immunoglobin in nature and bind to the carbohydrate moiety of the glycoconjugates without altering any of the recognized glycosyl ligands. Plant lectins have found applications as cancer biomarkers for recognizing the malignant tumor cells for the diagnosis and prognosis of cancer. Interestingly, plant lectins contribute to inducing cell death through autophagy and apoptosis, indicating their potential implication in cancer inhibitory mechanism. In the present review, anticancer activities of major plant lectins have been documented, with a detailed focus on the signaling circuit for the possible molecular targeted cancer therapy. In this context, several lectins have exhibited preclinical and clinical significance, driving toward therapeutic potential in cancer treatment. Moreover, several plant lectins induce immunomodulatory activities, and therefore, novel strategies have been established from preclinical and clinical investigations for the development of combinatorial treatment consisting of immunotherapy along with other anticancer therapies. Although the application of plant lectins in cancer is still in very preliminary stage, advanced high-throughput technology could pave the way for the development of lectin-based complimentary medicine for cancer treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Lectinas de Plantas/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Humanos , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Neoplasias/imunologia , Neoplasias/patologia , Lectinas de Plantas/farmacologia
15.
Environ Monit Assess ; 188(7): 402, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27289470

RESUMO

The ambient air quality (AAQ) assessment was undertaken in Sukinda Valley, the chromite hub of India. The possible correlations of meteorological variables with different air quality parameters (PM10, PM2.5, SO2, NO2 and CO) were examined. Being the fourth most polluted area in the globe, Sukinda Valley has always been under attention of researchers, for hexavalent chromium contamination of water. The monitoring was carried out from December 2013 through May 2014 at six strategic locations in the residential and commercial areas around the mining cluster of Sukinda Valley considering the guidelines of Central Pollution Control Board (CPCB). In addition, meteorological parameters viz., temperature, relative humidity, wind speed, wind direction and rainfall, were also monitored. The air quality data were subjected to a general linear model (GLM) coupled with one-way analysis of variance (ANOVA) test for testing the significant difference in the concentration of various parameters among seasons and stations. Further, a two-tailed Pearson's correlation test helped in understanding the influence of meteorological parameters on dispersion of pollutants in the area. All the monitored air quality parameters varied significantly among the monitoring stations suggesting (i) the distance of sampling location to the mine site and other allied activities, (ii) landscape features and topography and (iii) meteorological parameters to be the forcing functions. The area was highly polluted with particulate matters, and in most of the cases, the PM level exceeded the National Ambient Air Quality Standards (NAAQS). The meteorological parameters seemed to play a major role in the dispersion of pollutants around the mine clusters. The role of wind direction, wind speed and temperature was apparent in dispersion of the particulate matters from their source of generation to the surrounding residential and commercial areas of the mine.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Meteorologia/métodos , Poluição Ambiental/análise , Índia , Mineração , Material Particulado/análise , Estações do Ano , Temperatura , Vento
16.
Chemosphere ; 359: 142343, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754491

RESUMO

The current research highlights the fabrication of a novel SnS2/CO32-@Ni-Co LDH (SnS2/NCL) by precipitating Ni-Co LDH over hydrothermally synthesized SnS2 nanoparticles for the enhanced degradation of thiamethoxam (THM) insecticide through the advanced oxidation process. The effect of several reaction parameters was optimized, and a maximum degradation of 98.1 ± 1.2 % with a rate constant of 0.0541 min-1 of 10 ppm THM was reached at a catalyst loading of 0.16 gL-1 using 0.3 mM of H2O2 within 70 min of visible light irradiation. The effect of metal cations, inorganic anions, dissolved organic matter, organic compounds and water samples on the photodegradation performance of SnS2/NCL nanocomposite was also examined to evaluate the prepared photocatalyst's suitability for use in actual wastewater conditions. The metal cations blocked the active sites of the photocatalyst and reduced the degradation efficiency except for Fe2+ ions, since it is a Fenton reagent and increased the production of hydroxyl radicals. Inorganic anions are the scavengers of hydroxyl radicals and hinder photocatalytic activity. Meanwhile, lake water containing varying degrees of co-existing ions shows the lowest degradation efficiency among other water samples. The SnS2/NCL nanocomposite could be reused for five cycles while maintaining a photocatalytic efficiency of 83.6 ± 0.3 % in the fifth run. The prepared SnS2/NCL nanocomposite also showed excellent photodegradation of several other emerging organic pollutants with an efficiency of over 80 % under optimum conditions. Incorporating Ni-Co LDH with SnS2 helped to delocalize photoinduced charges, leading to increased photocatalytic activity and a slower electron-hole recombination rate. The present research highlights the photocatalytic activity of SnS2/NCL photocatalysts for the photocatalytic degradation of emerging contaminants from wastewater.


Assuntos
Inseticidas , Fotólise , Tiametoxam , Compostos de Estanho , Poluentes Químicos da Água , Catálise , Tiametoxam/química , Inseticidas/química , Poluentes Químicos da Água/química , Compostos de Estanho/química , Sulfetos/química , Oxirredução , Nanocompostos/química , Níquel/química , Cobalto/química , Águas Residuárias/química , Luz , Peróxido de Hidrogênio/química
17.
Nanoscale Adv ; 6(11): 2741-2765, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38817430

RESUMO

Nanomaterials play a decisive role in environmental applications such as water purification, pollutant monitoring, and advanced oxidation-based remediation processes, particularly in semiconductor and metal sulfide-based photocatalysis. Metal sulfides are ideal for photocatalysis because of their unique optical, structural, and electronic characteristics. These properties enable the effective use of solar energy to drive various catalytic reactions with potential uses in environmental remediation with sustainable energy production. Among them, nickel sulfides (NiS) stand out for their narrow band gaps, high stability, and cost-effectiveness. This review thoroughly analyzes recent advancements in employing nickel-sulfide-based nanostructures for water decontamination. It begins by addressing environmental material needs and emphasizing the properties of nickel sulfide. To improve photocatalytic performance, controlled processes that affect the active structure, shape, composition, and size of nickel sulfide photocatalysts are examined, along with their synthesis methods. The heart of the review article is a detailed analysis of the modification of NiS through metal and non-metal doping, heterojunction, and nanocomposite formation for enhanced photocatalytic performance. The discussion also includes metal-modified nanostructures, metal oxides, and carbon-hybridized nanocomposites. This study underscores notable advancements in the degradation efficiency of NiS photocatalysts, rivaling their costly noble-metal counterparts. The analysis concludes with potential future directions for nickel sulfide-based photocatalysts in sustainable environmental remediation.

18.
RSC Adv ; 14(5): 3447-3472, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38259991

RESUMO

Boron nitride has gained wide-spread attention globally owing to its outstanding characteristics, such as a large surface area, high thermal resistivity, great mechanical strength, low density, and corrosion resistance. This review compiles state-of-the-art synthesis techniques, including mechanical exfoliation, chemical exfoliation, chemical vapour deposition (CVD), and green synthesis for the fabrication of hexagonal boron nitride and its composites, their structural and chemical properties, and their applications in hydrogen production and environmental remediation. Additionally, the adsorptive and photocatalytic properties of boron nitride-based nanocomposites for the removal of heavy metals, dyes, and pharmaceuticals from contaminated waters are discussed. Lastly, the scope of future research, including the facile synthesis and large-scale applicability of boron nitride-based nanomaterials for wastewater treatment, is presented. This review is expected to deliver preliminary knowledge of the present state and properties of boron nitride-based nanomaterials, encouraging the future study and development of these materials for their applications in various fields.

19.
Sci Rep ; 14(1): 18022, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39098951

RESUMO

Herein, a hydrothermal etching approach was used to generate an innovative CuS/O,N-CNT composite. The hydrothermal etching of g-C3N4 led to the creation of O,N-CNT, with ethanol as the oxygen source. The SEM and TEM characterizations confirmed the formation of CNT, whereas the XPS analysis proved the doping of oxygen and nitrogen in the CNT matrix along with the incorporation of CuS. Under sun irradiation, the produced CuS/O,N-CNT showed outstanding photocatalytic efficiency, eliminating methyl orange and methylene blue dyes with 97.21% and 98.11% efficacy, respectively. Adding hydrothermally etched O,N-CNT increased light absorption and charge migration kinetics, as can be studied from the UV-DRS and PL analysis; hence, the observed improvements in light absorption and charge transfer pathways contributed to the CuS/O,N-CNT composite's enhanced photocatalytic activity, indicating its potential for efficient elimination of organic contaminants under solar irradiation. The catalyst demonstrated high reusability performance up to six cycles and significantly degraded other dyes. Scavenger analysis, along with VB-XPS and UV-DRS analysis, aid in developing a photocatalytic mechanism that confirms the participation of hydroxyl and superoxide radicals in the degradation process.

20.
Sci Rep ; 14(1): 1118, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212420

RESUMO

The current study reported a facile co-precipitation technique for synthesizing novel NiCo2S4/chitosan nanocomposite. The photocatalytic activity of the prepared nanocomposite was evaluated using congo red (CR) dye as a target pollutant. The central composite design was employed to examine the impact of different reaction conditions on CR dye degradation. This study selected the pH, photocatalyst loading, initial CR concentration and reaction time as reaction parameters, while the degradation efficiency (%) was selected as the response. A desirability factor of 1 suggested the adequacy of the model. Maximum degradation of 93.46% of 35 ppm dye solution was observed after 60 min of visible light irradiation. The response to surface methodology (RSM) is a helpful technique to predict the optimum reaction conditions of the photodegradation of CR dye. Moreover, NiCo2S4/Ch displayed high recyclability and reusability up to four consecutive cycles. The present study suggests that the prepared NiCo2S4/chitosan nanocomposite could prove to be a viable photocatalyst for the treatment of dye-contaminated wastewater.

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