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1.
Sci Rep ; 14(1): 8910, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632259

RESUMO

Landfill leachate forms when waste-inherent water and percolated rainfall transfer are highly toxic, corrosive, acidic, and full of environmental pollutants. The release of leachate from municipal solid waste (MSW) landfill sites poses a severe hazard to human health and aquatic life. This study examined the impact of leachate from Delhi's Ghazipur landfill on the nearby groundwater quality. Analysis of leachate samples was done to determine various parameters such as total dissolved solids (TDS), hardness, alkalinity, electrical conductivity, pH, BOD5, COD, nitrate, sulphate, chloride and iron, and presence of coliform bacteria. Significant dissolved elements (22,690-34,525 mg/L) were observed in the samples, indicated by the high conductivity value (1156-1405 mho/cm). However, a stable pH range (6.90-7.80) of leachate samples was observed due to high alkalinity concentrations between 2123 and 3256 mg/L. The inverse distance weighing (IDW) interpolation tool from QGIS 3.22.7 developed spatial interpolated models for each parameter across the Ghazipur area. The IDW interpolated graphs of various parameters over the whole study area confirmed these contaminations. In addition, leachate and groundwater samples were physio-chemically analyzed, and temporal fluctuation in landfill waste has also been studied. The temporal fluctuation results showed that when heat is produced, transmitted, and lost throughout the waste system, the maximum temperature position fluctuates over time. The findings of this study highlight the critical importance of landfill management in reducing groundwater contamination from MSW leachate.

2.
Sci Rep ; 14(1): 8611, 2024 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616197

RESUMO

This work describes the study of the removal of a refractory contaminant, i.e., Hexavalent chromium (Cr(VI)) from aqueous systems by a novel adsorbent comprising Cr(VI) tolerant bacteria and zero valent iron nanoparticle (nZVI). A gram-positive, rod-shaped bacteria used in the study were isolated from wastewater (WW) received from the effluent of leather industries. The adsorbents were prepared with bacteria, nZVI alone, and a combination of both. The adsorbent comprising both elements was found to remove Cr(VI) with a higher percentage (93%) and higher capacities (0.58 mg/g) as compared to adsorbent with bacteria (Cr(VI) removal = 63%, qe = 0.163 mg/g) or nanoparticles (Cr(VI) removal = 80%, qe = 0.45 mg/g) alone. The adsorbent worked best at neutral pH, and the removal became saturated after 90 min of incubation. Equilibrium studies with isotherm modeling suggested that the adsorption process follows sips isotherm (R2 = 0.9955), which is expected to bean intra-particle diffusion process before the actual adsorption. Process kinetics was modeled with pseudo-first order, pseudo-second order, and Vermeulen model. The diffusion coefficient determined by fitting the kinetic data to Vermeulen model was found to be 0.0000314 cm2/s. The adsorbent can be tested further for continuous flow processes to find more insights about the usage on a large scale.


Assuntos
Bactérias , Cromo , Nanopartículas , Adsorção , Ferro
3.
Eur Heart J Case Rep ; 8(3): ytae062, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38464468

RESUMO

Background: Infective endocarditis (IE) is a feared complication after surgical valve replacement accounting for 10% to 30% of all cases of IE. Our case is unique as we present a decompensated heart failure patient with IE who urgently needed mechanical circulatory support (MCS) to stabilize while IE was treated. We used Impella to bridge him to sterile state before heart transplant was done. This case highlights the importance of different strategies for bridge to heart transplant in decompensated heart failure patients with endocarditis. Case summary: We describe a case of 62-year-old male who initially presented with severe shortness of breath with minimal exertion, weight gain, and lower extremity oedema diagnosed with acute on chronic systolic heart failure (HF) exacerbation (ACC stage D, NYHA class IV). Initial blood cultures and extensive work-up for IE were negative. He continued to decompensate haemodynamically despite inotropic support and the decision was to proceed with durable left ventricular assist device (LVAD) as bridge to orthotopic heart transplantation (OHT). Immediately prior to LVAD implantation, patient's blood cultures became positive for Cutibacterium acnes. Echocardiogram revealed IE on bioprosthetic aortic valve. Patient therefore underwent urgent aortic valve replacement (AVR) and was stabilized with Impella 5.5. Discussion: We highlight a case where MCS with Impella was used as a bridge to transplant in a decompensated HF patient who was septic. Patient was listed for OHT but was found to be septic due to IE and had to undergo AVR to achieve infection source control prior to undergoing heart transplant. Impella was used effectively to stabilize ACC stage D/NYHA class IV patient while he recovered from AVR and endocarditis before his blood cultures cleared up and he was listed for OHT. He successfully underwent OHT after 3 weeks.

4.
Sci Rep ; 14(1): 4824, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413667

RESUMO

This study, centered on the Asan Wetland in Uttarakhand, examines the ecological impact of heavy metals on aquatic insects biodiversity. It highlights the detrimental effects of metals like chromium, mercury, and lead, stemming from natural and anthropogenic sources, on aquatic insects diversity. Aquatic insects, particularly sensitive to water quality, are emphasized as key indicators of environmental health, illustrating the importance of understanding and managing the influences on wetland ecosystems. Wetland ecosystems are vulnerable to various environmental stressors, including pollution from heavy metals. These toxic substances can alter water quality parameters, disrupt nutrient cycling, and negatively impact the biodiversity and ecological balance of the system. This study aimed to evaluate the impact of several heavy metals (namely Cd, As, Cu, Fe, Pb, Ni, Zn, Al, Cr) on the distribution and biodiversity of various aquatic insect species, including Coeleoptera, Diptera, Ephemeroptera, Odonata, Plecoptera, and Trichoptera. The research utilized data collected between November 2021 and October 2022 from specifically chosen sites (S1, S2, S3) within the Asan Wetland in Dehradun, Uttarakhand. After collecting and identifying samples, various statistical (Sorenson, Shannon-Weiner diversity index, Margelef index) and multivariate tests (CCA, PCA, One-way Anova), have been applied to show the effects of these parameters. This study offers significant findings regarding the distribution patterns of heavy metals, the abundance of aquatic insects, and their interconnectedness within the ecosystem of the Asan Wetland. The abundance of aquatic insects, represented by 13 genera belonging to 6 orders, was assessed at three different sites (S1, S2, and S3) within the wetland. It was concluded that the heavy metals concentration and aquatic insects' density increases and decreases vice-versa in monsoon and winter seasons might be due to unfavourable factors. These findings contribute to the understanding of ecological dynamics and potential impacts of heavy metals on aquatic biota in wetland environments.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Áreas Alagadas , Ecossistema , Monitoramento Ambiental , Metais Pesados/toxicidade , Metais Pesados/análise , Insetos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Medição de Risco , China , Sedimentos Geológicos
5.
Environ Res ; 249: 118320, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38331148

RESUMO

In a global context, trace element pollution assessment in complex multi-aquifer groundwater systems is important, considering the growing concerns about water resource quality and sustainability worldwide. This research addresses multiple objectives by integrating spatial, chemometric, and indexical study approaches, for assessing trace element pollution in the multi-aquifer groundwater system of the Al-Hassa Oasis, Saudi Arabia. Groundwater sampling and analysis followed standard methods. For this purpose, the research employed internationally recognized protocols for groundwater sampling and analysis, including standardized techniques outlined by regulatory bodies such as the United States Environmental Protection Agency (USEPA) and the World Health Organization (WHO). Average values revealed that Cr (0.041) and Fe (2.312) concentrations surpassed the recommended limits for drinking water quality, posing serious threats to groundwater usability by humans. The trace elemental concentrations were ranked as: Li < Mn < Co < As < Mo < Zn < Al < Ba < Se < V < Ni < Cr < Cu < B < Fe < Sr. Various metal(loid) pollution indices, including degree of contamination, heavy metal evaluation index, heavy metal pollution index, and modified heavy metal index, indicated low levels of groundwater pollution. Similarly, low values of water pollution index and weighted arithmetic water quality index were observed for all groundwater points, signifying excellent groundwater quality for drinking and domestic purposes. Spatial distribution analysis showed diverse groundwater quality across the study area, with the eastern and western parts displaying a less desirable quality, while the northern has the best, making water users in the former more vulnerable to potential pollution effects. Thus, the zonation maps hinted the necessity for groundwater quality enhancement from the western to the northern parts. Chemometric analysis identified both human activities and geogenic factors as contributors to groundwater pollution, with human activities found to have more significant impacts. This research provides the scientific basis and insights for protecting the groundwater system and ensuring efficient water management.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Oligoelementos , Poluentes Químicos da Água , Água Subterrânea/análise , Água Subterrânea/química , Arábia Saudita , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Oligoelementos/análise
6.
Int J Biol Macromol ; 254(Pt 3): 127465, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866583

RESUMO

Rapid growth in industrialization sectors, the wastewater treatment plants become exhausted and potentially not able to give desirable discharge standards. Many industries discharge the untreated effluent into the water bodies which affects the aquatic diversity and human health. The effective disposal of industrial effluents thus has been an imperative requirement. For decades nanocellulose based materials gained immense attraction towards application in wastewater remediation and emerged out as a new biobased nanomaterial. It is light weighted, cost effective, mechanically strong and easily available. Large surface area, versatile surface functionality, biodegradability, high aspect ratio etc., make them suitable candidate in this field. Majorly cellulose based nanomaterials are used in the form of cellulose nanocrystals (CNCs), cellulose nanofibers (CNFs), or bacterial nanocellulose (BNC). This review specifically describes about a variety of extraction methods to produced nanocellulose and also discusses the modification of nanocellulose by adding functionalities in its surface chemistry. We majorly focus on the utilization of nanocellulose based materials in water remediation for the removal of different contaminants such as dyes, heavy metals, oil, microbial colony etc. This review mainly emphasizes in ray of hope towards nanocellulose materials to achieve more advancement in the water remediation fields.


Assuntos
Nanofibras , Nanopartículas , Nanoestruturas , Humanos , Água , Nanoestruturas/química , Nanopartículas/química , Nanofibras/química , Celulose/química
7.
Sci Total Environ ; 912: 168881, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38042200

RESUMO

Polyfluoroalkyl and perfluoroalkyl (PFAS) chemicals are fluorinated and exhibit complicated behavior. They are determined and highly resistant to ecological modifications that render plants ecologically robust. Thermal stability and water and oil resistance are examples of material qualities. Their adverse consequences are causing increasing worry due to their bioaccumulative nature in humans and other creatures. Direct data indicates that PFAS exposure in humans causes endocrine system disruption, immune system suppression, obesity, increased cholesterol, and cancer. Several PFASs are present in drinking water at low doses and may harm people. These cancer-causing PFAS have caused concern for water bodies all around the globe. Analytical techniques are used to identify and measure PFAS in an aqueous medium (membrane). Furthermore, a deeper explanation is provided for PFAS removal methods, including mixed matrix membrane (MMM) technology. By removing over 99 % of the PFAS from wastewater, MMMs may effectively remove PFAS from sewage when the support matrix contains adsorbing components. Furthermore, we consider several factors affecting the removal of PFAS and practical sorption methods for PFAS onto various adsorbents.


Assuntos
Água Potável , Fluorocarbonos , Neoplasias , Poluentes Químicos da Água , Humanos , Águas Residuárias , Fluorocarbonos/análise , Poluentes Químicos da Água/análise
8.
Sci Rep ; 13(1): 22053, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38086843

RESUMO

Statistics show that the inhabitants of Poland are producing increasingly more household waste. This article attempts to determine the current level of development of Poland in the field of waste management concerning other EU countries and partner countries; identify trends in the mass of generated, segregated, and mixed municipal waste; and obtain an idea of the attitude of the Polish population toward sorting waste at the source to bring the country to a higher level of waste management. The empirical base is statistical data published on the website of the EU Data Explorer and the Central Statistical Office. The ranking of countries was determined by the TOPSIS method using a synthetic indicator based on the selected diagnostic features. The significance of the obtained ranks was tested using the non-parametric Friedman test (p < 0.01). We established that Poland has been consistently ranked 16th-17th over the past 5 years. Unfortunately, thus far, no systematic approach has been found to raise citizens' awareness, which may be due to the lack of the necessary amount of data. Researchers recommend investigating the sensitivity of the relationship between the generation of alternative energy from waste and the authorities' action.

9.
Sci Rep ; 13(1): 20599, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996644

RESUMO

Surface waterbodies being primary source of water for human consumption are being investigated for its quality globally. This study evaluated water quality in three rivers (River Nfifikh, Hassar and El Maleh) of Mohammedia prefecture, Morocco in terms of heavy metals occurrence during two seasons of winter and spring. The heavy metals analyzed were cadmium, iron, copper, zinc, and lead. Heavy metal pollution index was derived to quantify water quality and pollution. Hazard quotient and carcinogenic risk were calculated to determine possible health risk. Modelling and prediction were performed using random forest, support vector machine and artificial neural network. The heavy metal concentration was lower in the winter season than in the spring season. Heavy metal pollution index (H.P.I.) was in the range of 1.5-2 during the winter season and 2-3 during the spring season. In the Nfifikh river, Cd2+ and Fe were the main polluting heavy metal. H.Q. was < 1 in all three rivers, which signified no adverse health effect from exposure to heavy metals. However, carcinogenic risk assessment revealed that 1 in every 100 people was susceptible to cancer during the life span of 70 years. Based on the control point reference, it was found that Mohammedia prefecture as river water was already contaminated before it entered the prefecture boundary. This was again validated with the water lagoon Douar El Marja which is located near the industrial zones of Mohammedia prefecture. Future studies are required to investigate pollution of rivers prior to their entry in Mohammedia prefecture to identify potential source and adopt mitigation measures accordingly.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Qualidade da Água , Monitoramento Ambiental , Marrocos , Poluentes Químicos da Água/análise , Metais Pesados/análise , Rios , Algoritmos , Medição de Risco , China
10.
Sci Rep ; 13(1): 19995, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968362

RESUMO

Urea is recognized as one of the most frequently used adulterants in milk to enhance artificial protein content, and whiteness. Drinking milk having high urea concentrations which causes innumerable health disputes like ulcers, indigestion, and kidney-related problems. Therefore, herein, a simple and rapid electroanalytical platform was developed to detect the presence of urea in milk using a modified electrode sensor. Calcium oxide nanoparticles (CaO NPs) were green synthesized and used as a catalyst material for developing the sensor. Synthesized materials formation was confirmed by different techniques like FTIR, UV-visible, XRD, SEM-EDX, and Raman spectroscopy. The carbon paste electrode (CPE) was modified using the CaO NPs and used as a working electrode during the analysis followed by cyclic voltammetry and differential pulse voltammetry (DPV) techniques. The fabricated calcium oxide modified carbon paste electrode (CaO/CPE) successfully detected the presence of urea in the lower concentration range (lower limit of detection (LLOD) = 0.032 µM) having a wide linear detection range of 10-150 µM. Adsorption-controlled electrode process was achieved at the scan rate variation parameter. The leading parameters like the selectivity, repeatability, and stability of the CaO/CPE were investigated. The relative standard deviation of sensor was ± 3.8% during the interference and stability study.

11.
Chemosphere ; 345: 140465, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37866494

RESUMO

The present investigation reports a comprehensible and responsive strategy for identifying atrazine in several conditions using an extensive electrochemical method. CdS Quantum dots were synthesized via a greener approach, and their formation was endorsed by numerous characterization techniques such as FTIR, SEM, Raman, UV-Vis, and XRD. Owing to the splendid electrocatalytic behavior, Green CdS quantum dots (QDs) of crystallite size ∼2 nm was opted as the sensor material and were, therefore, incorporated on the bare carbon paste electrode's surface. The developed sensor demonstrated an impressive outcome for atrazine sensing accompanied by superior selectivity and sensitivity. The lower detection limit (LLOD) of 0.53 µM was attained using the developed sensor in a linear concentration range of 10-100 µM. Furthermore, the practical pertinence of the developed sensor was examined on distilled water, wastewater, and fresh liquid milk, resulting in a tremendous retrieval of atrazine (91.33-99.8%).


Assuntos
Atrazina , Água Potável , Pontos Quânticos , Pontos Quânticos/química , Atrazina/análise , Técnicas Eletroquímicas , Carbono/química
12.
Chemosphere ; 345: 140470, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37858768

RESUMO

Aquatic algal communities demonstrated their appeal for diverse industrial applications due to their vast availability, ease of harvest, lower production costs, and ability to biosynthesize valuable molecules. Algal biomass is promising because it can multiply in water and on land. Integrated algal systems have a significant advantage in wastewater treatment due to their ability to use phosphorus and nitrogen, simultaneously accumulating heavy metals and toxic substances. Several species of microalgae have adapted to thrive in these harsh environmental circumstances. The potential of algal communities contributes to achieving the United Nations' sustainable development goals in improving aquaculture, combating climate change, reducing carbon dioxide (CO2) emissions, and providing biomass as a biofuel feedstock. Algal-based biomass processing technology facilitates the development of a circular bio-economy that is both commercially and ecologically viable. An integrated bio-refinery process featuring zero waste discharge could be a sustainable solution. In the current review, we will highlight wastewater management by algal species. In addition, designing and optimizing algal bioreactors for wastewater treatment have also been incorporated.


Assuntos
Microalgas , Purificação da Água , Águas Residuárias , Nitrogênio , Dióxido de Carbono , Fósforo , Biomassa , Biocombustíveis
13.
Chemosphere ; 344: 140264, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37758081

RESUMO

Pollution problems are increasingly becoming e a priority issue from both scientific and technological points of view. The dispersion and frequency of pollutants in the environment are on the rise, leading to the emergence have been increasing, including of a new class of contaminants that not only impact the environment but also pose risks to people's health. Therefore, developing new methods for identifying and quantifying these pollutants classified as emerging contaminants is imperative. These methods enable regulatory actions that effectively minimize their adverse effects to take steps to regulate and reduce their impact. On the other hand, these new contaminants represent a challenge for current technologies to be adapted to control and remove emerging contaminants and involve innovative, eco-friendly, and sustainable remediation technologies. There is a vast amount of information collected in this review on emerging pollutants, comparing the identification and quantification methods, the technologies applied for their control and remediation, and the policies and regulations necessary for their operation and application. In addition, This review will deal with different aspects of emerging contaminants, their origin, nature, detection, and treatment concerning water and wastewater.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Humanos , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Águas Residuárias
14.
J Environ Manage ; 345: 118815, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37633104

RESUMO

This investigation is centered on the effectiveness of methylene blue (MB), a cationic dye, adsorbed from an aqueous media by H3PO4 activated papaya skin/peels (PSPAC), with initial pH (2-10), contact time (30-180 min), MB dye concentration (varying from 10 to 50 mg/L), and MB dose (0.1-0.5 gm). The findings show that the best optimal conditions for MB dye removal occur at a 6 pH, 0.3 gm dose of PSPAC adsorbent for 10 mg/L MB dye concentration, with 90 min of contact time. To optimize and validate the extraction efficiency of MB dye, a response surface methodology (RSM) study was conducted using a central composite design (CCD) with a regression model showing R2 = 0.9940. FT-IR spectroscopy shows, CO, and O-H stretching functional groups while FE-SEM is assessed to supervise morphological features of the PSPAC adsorbent. The peak adsorption capacity with 46.95 mg/g for the Langmuir isotherm model conveniently satisfies the adsorption process with R2 = 0.9984 while with R2 = 0.999, a kinetic model, pseudo-second-order, confirms MB dye adsorption by PSPAC adsorbent. Moreover, thermodynamic parameters including ΔGᵒ, ΔH°, and ΔS° were computed and found to be spontaneous and exothermic. Furthermore, regeneration studies employed with NaOH (0.1 M) and HCl (0.1 M) solution media show an acceptable MB removal efficiency consecutive up to three cycles. The study highlights that H3PO4 papaya skin/peel (PSPAC) is an effectual, sustainable, reasonably available biosorbent to remove industrial cationic dyes disposal.


Assuntos
Carica , Poluentes Químicos da Água , Azul de Metileno/química , Corantes/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio , Termodinâmica , Água , Adsorção
15.
Sci Rep ; 13(1): 13147, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573375

RESUMO

The aluminum nanocomposite is fabricated through squeeze stir casting method where CNT, SiC/B4C powder has been used as a reinforcement in an aluminum matrix. Squeeze action in stir casting opted due to proper reinforcement of 2 vol% of CNT in the matrix. The boron carbide and silicon carbide have been added by 8 and 12 vol% in the matrix. Uniform distribution of reinforcement and phase analysis has been shown by scanning electron microscopy (SEM) and XRD analysis. The formation of intermetallic compounds like Al3BC and Al4C3, dislocation forests, and the interaction of the reinforcement with the matrix are all confirmed by transmission electron microscopy (TEM). The micro-mechanical behavior of aluminum nanocomposites was investigated using nano indentation. The nano hardness, Vickers hardness, and Young's modulus of 12 vol% B4C compared with 12 vol% of SiC are increased by 12%, 23%, and 16%, respectively, and the same trend has been observed for the 8 vol% B4C reinforced composite. The model analysis for Young's modulus has been done and the experimental value for the modulus of elasticity of the composite are validated and not find such differences significantly. The surface topography was determined, furrow scratches and wear scars, and it was discovered that B4C reinforced composites have reduced stripping pits inside the wear marks, as well as lower wear width and depth. Wear analysis is essential because abrasive encounters result in substantial damage owing to larger pits and bigger wear scars.

16.
Environ Res ; 236(Pt 2): 116808, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37579962

RESUMO

The development and operation of a nanosensor for detecting the poisonous 1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine (Atrazine) are described in this study for the first time. The carbon electrode (CE) surface was modified with cysteine-substituted naphthalene diimide to create this sensitive platform. The developed nanosensor (NDI-cys/GCE) was evaluated for its ability to sense Atrazine using differential pulse voltammetry and cyclic voltammetry. To achieve the best response from the target analyte, the effects of several parameters were examined to optimize the conditions. The cysteine-substituted naphthalene diimide significantly improved the signals of the Atrazine compared to bare GCE due to the synergistic activity of substituted naphthalene diimide and cysteine molecules. Under optimal conditions, atrazine detection limits at the (NDI-cys/GCE) were reported to be 94 nM with a linear range of 10-100 µM. The developed sensing platform also showed positive results when used to detect the atrazine herbicide in real tap water, wastewater, and milk samples. Furthermore, a reasonable recovery rate for real-time studies, repeatability, and stability revealed that the developed electrochemical platform could be used for sample analysis.

17.
Environ Res ; 235: 116598, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37451577

RESUMO

NixMg1-xFe2O4(x = 0, 0.2, 0.4, 0.6) nanoparticles were symphonized via combustion with microwave assistance in the presence of Tamarindus indica seeds extract as fuel. Nanoparticles nature, size, morphology, oxidation state, elemental composition, and optical and luminescence properties were analysed using PXRD, FTIR, SEM, EDX, and HRTEM with SAED, XPS, UV-Visible and photoluminescence spectroscopy. PXRD analysis confirms that synthesized nanoparticles are spinel cubic and have a 17-18 nm average crystalline size. Tetrahedral and octahedral sites regarding stretching vibrations were confirmed by FTIR analysis. SEM and HRTEM data it is disclosed that the morphology of synthesized nanoparticles has nano flakes-like structure with sponge-like agglomeration. Elemental compositions of prepared nanoparticles were confirmed through EDX spectroscopy. XPS Spectroscopy confirmed and revealed transition, oxidation states, and elemental composition. The band gap and absorption phenomenon were disclosed using UV-visible spectroscopy, where the band gap declines (2.1, 2, 1.6, 1.8 eV), with increase in nickel NixMg1-xFe2O4(x = 0, 0.2, 0.4, 0.6) doping. Photoluminescence intensity reduces with an incline in nickel doping, was confirmed and disclosed using photoluminescence spectroscopy. Dyes (Methylene blue and Rhodamine B) degradation activity was performed in the presence of NDMF nanoparticles as a photocatalyst, which disclosed that 98.1% of MB dye and 97.9% of RB dye were degraded in 0-120 min. Regarding initial dye concentration and catalyst load, 5 ppm was initiated as the ideal initial concentration for both RB and MB dyes. 50 mg catalyst dosage was found to be most effective for the degradation of MB and RB dyes. In comparison, pH studies revealed that photodegradation efficiency was higher in neutral (MB-98.1%, RB-97.9%) and basic (MB-99.6%, RB-99.3%) conditions than in acidic (MB-61.8%, RB-60.4%) conditions.


Assuntos
Nanopartículas , Níquel , Magnésio , Micro-Ondas , Nanopartículas/química , Corantes
18.
J Environ Manage ; 342: 118331, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37315466

RESUMO

Implementing unified municipal solid waste management (MSWM) is often difficult due to socio-economic variables. However, spatial GIS models and statistical analysis of solid waste characterized by the weekdays, weekends, and festivals can somewhat mitigate the variance and assist with selecting suitable waste management methods. This paper presents the example of Rajouri, India, to propose a suitable MSWM based on Inverse Distance Weighted (IDW) intensity maps and statistical findings. The considered region was divided into different sample sites based on the local population density, and Municipal Solid Waste (MSW) was collected from four locations in each site on weekdays, weekends, and festivals. Compositional analysis of the MSW was then used to generate spatial IDW models in QGIS 3.22.7 to interpolate MSW generation over the entire area. Finally, statistical analysis was conducted to gain insight into the waste generation and accumulation trends. The results show that Rajouri produces 245 tonnes of waste daily (per capita: 0.382 kg/day) with a large organic fraction compared to other waste categories. Besides, waste generation is observed to increase over weekends and festivals due to increased consumption of material goods. Composting could serve as a vector for municipal solid waste because of its increased organic component and cost constraints. However, further research on the potential segregation techniques for the organic fraction of solid waste is needed.


Assuntos
Compostagem , Eliminação de Resíduos , Gerenciamento de Resíduos , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Índia , Cidades
19.
Environ Sci Pollut Res Int ; 30(35): 84200-84218, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37365361

RESUMO

In the current work, the hybrid process potential of ultrasound (US) and electro-Fenton (EF), named sono-electro-Fenton (SEF), was fully investigated for sulfadiazine (SDZ) degradation. The decontamination in the integration approach was revealed to be greater than in individual procedures, i.e., EF process (roughly 66%) and US process (roughly 15%). The key operating process factors (i.e., applied voltage, H2O2 content, pH, initial concentration of SDZ, and reaction time) affecting SDZ removal were evaluated and optimized using Box-Behnken Design (BBD). In addition, an adaptive neuro-fuzzy inference system (ANFIS) as an efficient predictive model was applied to forecast the decontamination efficiency of SDZ through the SEF process based on the same findings produced from BBD. The results revealed that the predictability of SDZ elimination by the ANFIS and BBD approaches exhibited an excellent agreement (a greater R2 of 0.99%) among the both models. Density functional theory was also employed to forecast the plausible decomposition elucidation by the bond-breaking mechanism of organic substances. Plus, the main side products of SDZ degradation during the SEF process were tracked. Eventually, the non-carcinogenic risk assessment of different samples of natural water containing SDZ that was treated by adopting US, EF, and SEF processes was examined for the first time. The findings indicated that the non-carcinogenic risk (HQ) values of all the purified water sources were computed in the permissible range.


Assuntos
Sulfadiazina , Poluentes Químicos da Água , Humanos , Teoria da Densidade Funcional , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/análise , Água , Oxirredução
20.
Environ Monit Assess ; 195(6): 658, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37166547

RESUMO

The present study captures the precipitation synthesis of zinc nanoparticles and modification with alumina and oleic acid. The crystalline size evaluated from the XRD profile of the zinc oxide nanoparticles was 18.05 nm but was reduced to 14.20 and 14.50 nm upon modification with oleic acid and alumina. The XRD spectra also showed evidence of the amorphous nature of zinc oxide nanoparticles and subsequent enhancement upon modification. A porous appearance was observed in the SEM instrumentation but seems to be enhanced by modification. The FTIR absorption spectra of the nanoparticles showed a peak associated with ZnO vibration around 449 cm, but the enhanced intensity was observed due to modification. The prepared ZnO-NPs and the modified samples were good materials for the adsorption removal of glyphosate from water, recording efficiencies above 94% at neutral pH and showing a possible incremental trend with an enhanced period of contact and adsorbent dosage. The adsorbents showed maximum capacity that ranged from 82.85 to 82. 97 mg/g. The adsorption models of Freundlich, Temkin, Dubinin-Radushkevich and BET showed excellent fitness. Results from computational results complemented experimental data and were used to identify the sites for adsorption and characteristics of molecular descriptors for the systems.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Praguicidas , Poluentes Químicos da Água , Óxido de Zinco , Óxido de Zinco/química , Nanopartículas Metálicas/química , Ácido Oleico , Zinco , Monitoramento Ambiental , Nanopartículas/química , Água/química , Óxido de Alumínio , Adsorção , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio , Glifosato
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