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1.
Analyst ; 149(11): 3245-3262, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38687206

RESUMEN

Artificial superhydrophobic surfaces that do not absorb water, like the lotus leaf, show tremendous promise in numerous applications. However, superhydrophobic surfaces are rarely used because of their low stability and endurance. A stable organic superhydrophobic surface (SHS) composed of novel morphology Ag-nanoparticles (NPs) has been fabricated on a copper alloy via etching, immersion, spraying, and annealing treatment, along with a static water contact angle (WCA) of 158 ± 1° and sliding angle (SA) less than 2°. The surface texture, composition, and morphology of the substrate surfaces were explored by using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, and DFT-based Ag atom distribution. The anti-corrosion study of non-coated and Ag-NP-coated copper alloy was undertaken using electrochemical impedance spectroscopy. Ag-NPs +SA@SHS enhanced the corrosion resistance as compared with bare Cu alloy. The water droplet rolled down the coated Cu alloy, removed the chalk powder from the surface, and indicated an excellent self-cleaning function. Photodegradation of Congo red (CR) and methylene blue (MB) dye samples was assessed by measuring the absorbance through UV-Visible spectrophotometry, where the Ag-NPs coated on the copper alloy were used as a catalyst. The performance of the SHS@Ag-NPs in the aqueous solution was 99.31% and 98.12% for industrial pollutants (CR and MB), with degradation rates of 5.81 × 10-2 s-1 and 5.89 × 10-2 s-1, respectively. These findings demonstrated a simple, rapid, and low-energy fabrication technique for SHS@Ag-NPs. This research reveals a valuable approach for the fabrication of SHS@Ag-NPs on various substrates to extend the superhydrophobic surfaces with ultra-fast self-healing properties, for outdoor applications such as anti-corrosion, for an innovative approach for the remediation of polluted water treatment, and for industrial applications.

2.
Chem Rec ; 23(2): e202200149, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36408911

RESUMEN

Recently, the growing demand for a renewable and sustainable fuel alternative is contingent on fuel cell technologies. Even though it is regarded as an environmentally sustainable method of generating fuel for immediate concerns, it must be enhanced to make it extraordinarily affordable, and environmentally sustainable. Hydrogen (H2 ) synthesis by electrochemical water splitting (ECWS) is considered one of the foremost potential prospective methods for renewable energy output and H2 society implementation. Existing massive H2 output is mostly reliant on the steaming reformation of carbon fuels that yield CO2 together with H2 and is a finite resource. ECWS is a viable, efficient, and contamination-free method for H2 evolution. Consequently, developing reliable and cost-effective technology for ECWS was a top priority for scientists around the globe. Utilizing renewable technologies to decrease total fuel utilization is crucial for H2 evolution. Capturing and transforming the fuel from the ambient through various renewable solutions for water splitting (WS) could effectively reduce the need for additional electricity. ECWS is among the foremost potential prospective methods for renewable energy output and the achievement of a H2 -based economy. For the overall water splitting (OWS), several transition-metal-based polyfunctional metal catalysts for both cathode and anode have been synthesized. Furthermore, the essential to the widespread adoption of such technology is the development of reduced-price, super functional electrocatalysts to substitute those, depending on metals. Many metal-premised electrocatalysts for both the anode and cathode have been designed for the WS process. The attributes of H2 and oxygen (O2 ) dynamics interactions on the electrodes of water electrolysis cells and the fundamental techniques for evaluating the achievement of electrocatalysts are outlined in this paper. Special emphasis is paid to their fabrication, electrocatalytic performance, durability, and measures for enhancing their efficiency. In addition, prospective ideas on metal-based WS electrocatalysts based on existing problems are presented. It is anticipated that this review will offer a straight direction toward the engineering and construction of novel polyfunctional electrocatalysts encompassing superior efficiency in a suitable WS technique.

3.
Chem Rec ; 23(1): e202200143, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36285706

RESUMEN

The increasing demand for searching highly efficient and robust technologies in the context of sustainable energy production totally rely onto the cost-effective energy efficient production technologies. Solar power technology in this regard will perceived to be extensively employed in a variety of ways in the future ahead, in terms of the combustion of petroleum-based pollutants, CO2 reduction, heterogeneous photocatalysis, as well as the formation of unlimited and sustainable hydrogen gas production. Semiconductor-based photocatalysis is regarded as potentially sustainable solution in this context. g-C3 N4 is classified as non-metallic semiconductor to overcome this energy demand and enviromental challenges, because of its superior electronic configuration, which has a median band energy of around 2.7 eV, strong photocatalytic stability, and higher light performance. The photocatalytic performance of g-C3 N4 is perceived to be inadequate, owing to its small surface area along with high rate of charge recombination. However, various synthetic strategies were applied in order to incorporate g-C3 N4 with different guest materials to increase photocatalytic performance. After these fabrication approaches, the photocatalytic activity was enhanced owing to generation of photoinduced electrons and holes, by improving light absorption ability, and boosting surface area, which provides more space for photocatalytic reaction. In this review, various metals, non-metals, metals oxide, sulfides, and ferrites have been integrated with g-C3 N4 to form mono, bimetallic, heterojunction, Z-scheme, and S-scheme-based materials for boosting performance. Also, different varieties of g-C3 N4 were utilized for different aspects of photocatalytic application i. e., water reduction, water oxidation, CO2 reduction, and photodegradation of dye pollutants, etc. As a consequence, we have assembled a summary of the latest g-C3 N4 based materials, their uses in solar energy adaption, and proper management of the environment. This research will further well explain the detail of the mechanism of all these photocatalytic processes for the next steps, as well as the age number of new insights in order to overcome the current challenges.

4.
Chem Rec ; 23(5): e202200171, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37066717

RESUMEN

Graphitic carbon nitride (g-C3 N4 ) has gained tremendous interest in the sector of power transformation and retention, because of its distinctive stacked composition, adjustable electronic structure, metal-free feature, superior thermodynamic durability, and simple availability. Furthermore, the restricted illumination and extensive recombination of photoexcitation electrons have inhibited the photocatalytic performance of pure g-C3 N4 . The dimensions of g-C3 N4 may impact the field of electronics confinement; as a consequence, g-C3 N4 with varying dimensions shows unique features, making it appropriate for a number of fascinating uses. Even if there are several evaluations emphasizing on the fabrication methods and deployments of g-C3 N4 , there is certainly an insufficiency of a full overview, that exhaustively depicts the synthesis and composition of diverse aspects of g-C3 N4 . Consequently, from the standpoint of numerical simulations and experimentation, several legitimate methodologies were employed to deliberately develop the photocatalyst and improve the optimal result, including elements loading, defects designing, morphological adjustment, and semiconductors interfacing. Herein, this evaluation initially discusses different dimensions, the physicochemical features, modifications and interfaces design development of g-C3 N4 . Emphasis is given to the practical design and development of g-C3 N4 for the various power transformation and inventory applications, such as photocatalytic H2 evolution, photoreduction of CO2 source, electrocatalytic H2 evolution, O2 evolution, O2 reduction, alkali-metal battery cells, lithium-ion batteries, lithium-sulfur batteries, and metal-air batteries. Ultimately, the current challenges and potential of g-C3 N4 for fuel transformation and retention activities are explored.

5.
Chem Rec ; 22(12): e202200097, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36103617

RESUMEN

Use of MXenes (Ti3 C2 Tx ), which belongs to the family of two-dimensional transition metal nitrides and carbides by encompassing unique combination of metallic conductivity and hydrophilicity, is receiving tremendous attention, since its discovery as energy material in 2011. Owing to its precursor selective chemical etching, and unique intrinsic characteristics, the MXene surface properties are further classified into highly chemically active compound, which further produced different surface functional groups i. e., oxygen, fluorine or hydroxyl groups. However, the role of surface functional groups doesn't not only have a significant impact onto its electrochemical and hydrophilic characteristics (i. e., ion adsorption/diffusion), but also imparting a noteworthy effect onto its conductivity, work function, electronic structure and properties. Henceforth, such kind of inherent chemical nature, robust electrochemistry and high hydrophilicity ultimately increasing the MXene application as a most propitious material for overall environment-remediation, electrocatalytic sensors, energy conversion and storage application. Moreover, it is well documented that the role of MXenes in all kinds of research fields is still on a progress stage for their further improvement, which is not sufficiently summarized in literature till now. The present review article is intended to critically discuss the different chemical aptitudes and the diversity of MXenes and its derivates (i. e., hybrid composites) in all aforesaid application with special emphasis onto the improvement of its surface characteristics for the multidimensional application. However, this review article is anticipated to endorse MXenes and its derivates hybrid configuration, which is discussed in detail for emerging environmental decontamination, electrochemical use, and pollutant detection via electrocatalytic sensors, photocatalysis, along with membrane distillation and the adsorption application. Finally, it is expected, that this review article will open up new window for the effective use of MXene in a broad range of environmental remediation, energy conversion and storage application as a novel, robust, multidimensional and more proficient materials.

6.
Int J Phytoremediation ; 23(4): 336-346, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32898432

RESUMEN

Synthetic dye waste is one of the world's key ecological concerns. The algal biomass has emerged as a promising alternative adsorbent for wastewater treatment. The present study deals with the functionalization of brown algae (BA) by citric acid in order to improve its adsorption ability for textile dye removal in aqueous solutions. The morphological texture (SEM and BET) and surface chemistry (FTIR, EDS-mapping, and PZC) of the novel functionalized brown algae (designated as BA-CA) were analyzed. The performance of BA-CA for crystal violet (CV) dye removal from wastewater was investigated. The isotherm and kinetic adsorption modeling indicate the good fit of Langmuir isotherm and pseudo-second-order models. Optimum monolayer uptake capacity was 279.14 mg/g for BA-CA, which was about two times higher than that of unmodified BA. The thermodynamic parameters clearly indicated that CV removal process was physiosorption, exothermic, and spontaneous in nature. The regeneration study showed excellent reusability of the BA-CA up to five cycles. Overall, the experimental findings lead us to conclude that the BA-CA can be used as an eco-friendly, cost-effective and easily regenerated adsorbent for the purification of textile effluents.


Asunto(s)
Phaeophyceae , Contaminantes Químicos del Agua , Adsorción , Biodegradación Ambiental , Ácido Cítrico , Violeta de Genciana , Concentración de Iones de Hidrógeno , Cinética , Termodinámica , Aguas Residuales
7.
Water Sci Technol ; 84(9): 2265-2277, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34810310

RESUMEN

A novel arginine-modified Heliotrope leaf (Arg@HL) was used as adsorbent for the crystal violet (CV) dye adsorption in a batch process. The physicochemical and morphological composition of Arg@HL were characterized by field-emission scanning electron microscopy (FE-SEM), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The experiments were carried out to investigate the factors that influence the dye uptake by the adsorbent, such as the contact time under agitation, adsorbent amount, initial dye concentration, temperature and pH of dye solution. The optimum conditions of adsorption were found on the batch scale as followed: CV concentration of 20 mg·L-1, an amount of 0.75 g·L-1 of the adsorbent, 90 min contact time, 6 pH and 25 °C temperature for Arg@HL. The results confirmed a second-order model explaining the dye crystal violet's adsorption's kinetics by Arg-Heliotrope leaves. The Langmuir model effectively defines the adsorption isotherms. The results revealed that the Arg@HL has the potential to be used as a low-cost adsorbent for the removal of CV dye from aqueous solutions.


Asunto(s)
Violeta de Genciana , Contaminantes Químicos del Agua , Arginina , Concentración de Iones de Hidrógeno , Hojas de la Planta , Termodinámica
8.
J Environ Manage ; 253: 109730, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31665689

RESUMEN

Characterization of the driving forces for effective and economical phosphate (PO43-) removal from wastewater by using magnetically modified biochar was performed in this study. The biochar produced from slow pyrolysis of local agricultural biomass (wood and rice husks) were magnetically modified by co-precipitation of Fe(II) and Fe(III) ions in their presence. The surface characteristics before and after modification and their efficacy for PO43- sorption, and desorption were compared. Results show that, even though magnetic biochar surface modification slightly decreased their surface area, PO43- adsorption to the modified biochars was almost double (25-28 mg g-1) than that to the raw biochar (12-15 mg g-1). The adsorption isotherm of raw biochars was better simulated via the Langmuir model, while that of modified biochars was better fitted to the Freundlich model. Moreover, the integrated analysis by XRD, EDX, and FTIR show that PO43- sorption to modified biochars could be attributed to the simultaneously-occurring electrostatic attraction, surface precipitation, and ligand exchange. While the electrostatic attraction was dominant in the presence of unmodified biochars. The regenerated modified biochars retained substantial PO43- adsorption capacity up to several regeneration cycles. Their high reusability potential leads to the effective and economical phosphate recovery and thus modified biochars could offer a viable strategy for PO43- removal.


Asunto(s)
Compuestos Férricos , Fosfatos , Adsorción , Biomasa , Carbón Orgánico
9.
J Environ Manage ; 264: 110477, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250903

RESUMEN

Structural variations of a mineral dictate its adsorption capacity which affects the mobility and toxicity of contaminants in natural and engineered systems. Present batch study evaluates the adsorption of lead (Pb) and cadmium (Cd) onto three magnetites having nanometric (M1-30 nm and M2-60 nm) and micrometric particle sizes (M3-1.5 µm). Obtained data revealed that particle size of tested magnetites strongly affected the extent and kinetics of metal adsorption and desorption. Observed order of adsorption efficiency was M1 > M2 > M3 with optimum monolayer adsorption of 408.14, 331.40, 178.47 mg/g (for Pb) and 228.05, 170.86, 83.49 mg/g (for Cd), respectively. Adsorption data were well fitted to the Freundlich (R2 = 0.99), Langmuir (R2 = 0.99) and pseudo-first order models (R2 = 0.98). Electrostatic attraction and surface precipitation interaction via external mass transfer between bulk liquid-solid interfaces were the potential adsorption pathways. Pb showed higher affinity than Cd in multi-metal system. Desorption efficiency was higher in acidic environment (92%) than in distilled water (44%). Moreover, regenerated magnetite samples retained good adsorption capacity for six cycles. As soils are characterized by large variability of iron minerals, these findings have important implications regarding the transport and immobilization of contaminants particularly in the management of contaminated soils.


Asunto(s)
Cadmio , Plomo , Adsorción , Óxido Ferrosoférrico , Cinética , Suelo
12.
J Environ Manage ; 201: 260-267, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28672198

RESUMEN

Four slow pyrolyzed biochars produced from wood (WDB), corncobs (CCB), rice husks (RHB) and sawdust (SDB) were evaluated for adsorption, desorption and regeneration of phosphate (PO43--P) from anaerobically digested liquid swine manure. The PO43--P adsorption capacity increased followed by initial concentrations increasing. Maximum PO43--P adsorptions at initial 150 mg/L of PO43--P (highest load) were average of 7.67, 6.43, 5.73 and 5.41 mg/g for WDB, CCB, RHB and SDB, respectively. Pseudo second order kinetics model could best fit PO43--P adsorption, which indicated the chemisorption via precipitation was the main mechanism for PO43--P removal. The sorption process was reversible and the adsorbed PO43--P could be desorbed in both neutral (57-78%) and acidic solution environments (75-88%) for all biochars. Meanwhile, regenerated biochar could re-adsorb up to 5.62 mg/g at the highest initial PO43--P of 150 mg/L. The present finding implied biochar could be effectively used to recover PO43--P from anaerobic digestate.


Asunto(s)
Carbón Orgánico , Fosfatos , Adsorción , Animales , Porcinos
13.
Cureus ; 16(5): e60678, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38899238

RESUMEN

Malaria remains a significant global health challenge, with Plasmodium parasites transmitted by Anopheles mosquitoes causing substantial morbidity and mortality. Despite historical efforts, malaria continues to affect millions worldwide, particularly in tropical regions. This systematic review aimed to assess the acceptability of the RTS, S/AS01 malaria vaccine among diverse populations. A comprehensive search strategy was employed across databases such as Cochrane Library, Embase, Google Scholar, and Medline. Studies were included based on specific criteria, including observational and cross-sectional designs involving adults. Data extraction and analysis were conducted meticulously, encompassing key variables related to vaccine acceptance rates and influencing factors. Analysis of 18 studies involving 18,561 participants revealed an overall malaria vaccine acceptance rate of 87.51%, ranging from 32.26% to 99.30%. Significant variations were observed based on demographics, with Ghana and Nigeria reporting high acceptance rates. Factors influencing acceptance included knowledge levels, past vaccination experiences, community preferences, and engagement in malaria prevention behaviors. Concerns about adverse reactions and regional disparities were noted as potential barriers to acceptance. This review highlights the importance of understanding public perceptions and concerns regarding malaria vaccines to enhance vaccine coverage and uptake. Tailored communication strategies, advocacy efforts, and targeted education interventions are crucial for addressing misconceptions and increasing vaccine acceptance. Policy recommendations should consider demographic and regional factors to ensure effective implementation of malaria vaccination programs, ultimately contributing to global malaria prevention efforts and public health initiatives.

14.
J Hazard Mater ; 466: 133543, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38262318

RESUMEN

The prevalence of organophosphate esters (OPEs) in the global environment is increasing, which aligns with the decline in the usage of polybrominated diphenyl ethers (PBDEs). PBDEs, a category of flame retardants, were banned and classified as persistent organic pollutants (POPs) through the Stockholm Convention due to their toxic and persistent properties. Despite a lack of comprehensive understanding of their ecological and health consequences, OPEs were adopted as replacements for PBDEs. This research aims to offer a comparative assessment of PBDEs and OPEs in various domains, specifically focusing on their persistence, bioaccumulation, and toxicity (PBT) properties. This study explored physicochemical properties (such as molecular weight, octanol-water partition coefficient, octanol-air partition coefficient, Henry's law constant, and vapor pressures), environmental behaviors, global concentrations in environmental matrices (air, water, and soil), toxicities, bioaccumulation, and trophic transfer mechanisms of both groups of compounds. Based on the comparison and analysis of environmental and toxicological data, we evaluate whether OPEs represent another instance of regrettable substitution and global contamination as much as PBDEs. Our findings indicate that the physical and chemical characteristics, environmental behaviors, and global concentrations of PBDEs and OPEs, are similar and overlap in many instances. Notably, OPE concentrations have even surged by orders of several magnitude compared to PBDEs in certain pristine regions like the Arctic and Antarctic, implying long-range transport. In many instances, air and water concentrations of OPEs have been increased than PBDEs. While the bioaccumulation factors (BAFs) of PBDEs (ranging from 4.8 to 7.5) are slightly elevated compared to OPEs (-0.5 to 5.36) in aquatic environments, both groups of compounds exhibit BAF values beyond the threshold of 5000 L/kg (log10 BAF > 3.7). Similarly, the trophic magnification factors (TMFs) for PBDEs (ranging from 0.39 to 4.44) slightly surpass those for OPEs (ranging from 1.06 to 3.5) in all cases. Metabolic biotransformation rates (LogKM) and hydrophobicity are potentially major factors deciding their trophic magnification potential. However, many compounds of PBDEs and OPEs show TMF values higher than 1, indicating biomagnification potential. Collectively, all data suggest that PBDEs and OPEs have the potential to bioaccumulate and transfer through the food chain. OPEs and PBDEs present a myriad of toxicity endpoints, with notable overlaps encompassing reproductive issues, oxidative stress, developmental defects, liver dysfunction, DNA damage, neurological toxicity, reproductive anomalies, carcinogenic effects, and behavior changes. Based on our investigation and comparative analysis, we conclude that substituting PBDEs with OPEs is regrettable based on PBT properties, underscoring the urgency for policy reforms and effective management strategies. Addressing this predicament before an exacerbation of global contamination is imperative.


Asunto(s)
Retardadores de Llama , Éteres Difenilos Halogenados , Éteres Difenilos Halogenados/toxicidad , Éteres Difenilos Halogenados/análisis , Monitoreo del Ambiente , Organofosfatos/análisis , Agua/análisis , Retardadores de Llama/toxicidad , Retardadores de Llama/análisis , Octanoles , Ésteres/toxicidad
15.
Adv Colloid Interface Sci ; 319: 102969, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37598456

RESUMEN

Carbon materials technology provides the possibility of synthesizing low-cost, outstanding performance replacements to noble-metal catalysts for long-term use. Graphdiyne (GDY) is a carbon allotrope with an extremely thin atomic thickness. It consists of carbon elements, that are hybridized with both sp. and sp2, resulting in a multilayered two-dimensional (2D) configuration. Several functional models suggest, that GDY contains spontaneously existing band structure with Dirac poles. This is due to the non-uniform interaction among carbon atoms, which results from various fusions and overlapping of the 2pz subshell. Unlike other carbon allotropes, GDY has Dirac cone arrangements, that in turn give it inimitable physiochemical characteristics. These properties include an adjustable intrinsic energy gap, high speeds charging transport modulation efficiency, and exceptional conductance. Many scientists are interested in such novel, linear, stacked materials, including GDY. As a result, organized synthesis of GDY has been pursued, making it one of the first synthesized GDY materials. There are several methods to manipulate the band structure of GDY, including applying stresses, introducing boron/nitrogen loading, utilizing nanowires, and hydrogenations. The flexibility of GDY can be effectively demonstrated through the formation of nano walls, nanostructures, nanotube patterns, nanorods, or structured striped clusters. GDY, being a carbon material, has a wide range of applications owing to its remarkable structural and electrical characteristics. According to subsequent research, the GDY can be utilized in numerous energy generation processes, such as electrochemical water splitting (ECWS), photoelectrochemical water splitting (PEC WS), nitrogen reduction reaction (NRR), overall water splitting (OWS), oxygen reduction reaction (ORR), energy storage materials, lithium-Ion batteries (LiBs) and solar cell applications. These studies suggested that the use of GDY holds significant potential for the development and implementation of efficient, multimodal, and intelligent catalysts with realistic applications. However, the limitation of GDY and GDY-based composites for forthcoming studies are similarly acknowledged. The objective of these studies is to deliver a comprehensive knowledge of GDY and inspire further advancement and utilization of these unique carbon materials.

16.
Chemosphere ; 341: 140095, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37683953

RESUMEN

In this study, novel stannous oxide@hafnium carbide (SnO@HfC) nanocomposite was successfully manufactured by an appropriate hydrothermal scheme which was utilized for the photocatalytic degradation of BPA by stimulation of peroxymonosulfate (PMS) and self-cleaning application. Numerous methods were applied for the characterization of photocatalyst and demonstrated the successful preparation of SnO@HfC nanocomposite. The crystal structures, band structures and density of states for SnO and HfC were explored by DFT analysis. The amazing PMS stimulation performance of SnO@HfC nanocomposite originated from the establishment of a heterojunction, which led to the enhancement of the light response aptitude and the electron conduction competence of the composite. BPA was degraded by 0.75 g/L PMS and SnO@HfC at neutral pH during the period of 60 min. In order to identify active groups in the reaction procedure, quenching experiments and electron paramagnetic resonance (EPR) approaches were also used. In the subsequent active species scavenging assays, where sulfate radicals, hydroxyl radicals, holes, and superoxide radicals were engaged in the degradation of BPA. While, liquid phase mass spectrometry (LC-MS) was used to pinpoint the intermediate metabolites in the course of degradation. SnO@HfC/PMS/light system delivered excellent TOC removal efficiency and less ions leaching. The SnO@HfC nanocomposite proved good durability and reusability in continuous cycle tests along with excellent self-cleaning function on the glass substrate. The SnO@HfC nanocomposite performs admirably in terms of self-cleaning application. The SnO@HfC nanocomposite is expected to be used in the future for the treatment of wastewater that contains pharmaceuticals due to its superior stability and reusability after five consecutive cycles.


Asunto(s)
Hafnio , Peróxidos , Superóxidos
17.
Sci Total Environ ; 863: 160765, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36513226

RESUMEN

Habitats of species and physicochemical factors are of great importance in determining the trophic transfer of contaminants in freshwater ecosystems. There is little information on how multiple physicochemical factors and habitats influence the trophic transfer of antibiotics in freshwater food webs. This study investigated the concentrations of 7 sulfonamides (SAs), 4 fluoroquinolones (FQs), 4 tetracyclines (TCs) and 2 macrolides (MLs) in the Lake Dianshan food web. Stable isotope analysis (SIA), and mathematical models were used to assign trophic levels and distinguish between the benthic food web (BFW) and pelagic food web (PFW). Values of stable nitrogen isotope (δ15N‰) and stable carbon isotope (δ13C‰) ranged from 10.2 ± 0.11 to 19.72 ± 0.05 and -33.67 ± 0.18 to -20.79 ± 0.50, respectively. Total concentrations of antibiotics ranged from 36.63 ± 12.73 ng/g dry weight (dw) to 105.85 ± 12.95 ng/g dw for all species. The relative abundance of antibiotics was in the following order: ∑FQs (36.49 %) > ∑SAs (26.70 %), >∑MLs (12.63 %) for all biotas. Trophic magnification factor (TMFs) values for individual antibiotics ranged from 0.10 to 1.20 and 0.31 to 1.82 for PFW and BFW, respectively. Three classes of antibiotics ∑FQs (p < 0.05), ∑TCs (p < 0.05), and ∑MLs (p < 0.05) showed significant trophic dilution in PFW, opposite to non-significant trophic dilution in BFW. The influence of various physicochemical factors was not strong over trophic transfer (e.g., octanol-water partition coefficient-LogKow (r = -0.05 in PFW, r = -0.14 in BFW) and distribution coefficient-LogD (r = 0.06 in PWF, r = -0.28 in BFW)) except for aqueous solubility (LogS). Results indicated a significantly higher trophic dilution of antibiotics in the PFW than in the BFW. Among the studied six physicochemical factors, only LogS significantly influences (p < 0.05) the trophic transfer of antibiotics in the freshwater food web. Health risk assessments indicated that currently, there were no serious risks present for urban and rural populations.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua , Animales , Humanos , Antibacterianos/análisis , Peces , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Cadena Alimentaria , Lagos/análisis , Isótopos de Carbono/análisis , Isótopos de Nitrógeno/análisis , Sulfanilamida , Fluoroquinolonas/análisis
18.
Sustain Cities Soc ; 83: 103962, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35634350

RESUMEN

The Sustainable Development Goals (SDGs) call on all nations to accomplish 17 broad global development goals by 2030. However, the COVID-19 pandemic presents a challenging period in human history, causing large-scale impacts on society and the environment as governments shift priorities and divert funding in response to this pandemic. Through a literature survey and data acquirement from various international organizations (e.g. United Nations and European Space Agency), this manuscript is intended to provide critical insights into the impacts of the COVID-19 pandemic on the SDGs. We briefly describe this pandemic's positive and short-term effects on the environment, followed by a critical evaluation of its potential long-term impacts on the environment, society, and the SDGs. On the basis of COVID-19 effects, the SDGs are classified into three categories: directly-affected SDGs, indirectly-affected SDGs, and a stand-alone category. The COVID-19-induced lockdowns and restrictions resulted in a short-term decline in environmental pollution and greenhouse gases (GHG) emissions, providing valuable data for climate advocates and researchers. These positive impacts were essentially temporary due to the synchronized global response to the pandemic. The halted focus on the progress of the SDGs greatly impacts the global green transition to a healthy and sustainable world. COVID-19 threatens to impede the progress toward a prosperous, environment-friendly, and sustainable global development in multiple ways. These multi-dimensional threats have been critically evaluated, along with a description of potential solutions to curtail the adverse effects of COVID-19 on the SDGs. Considering the limited data regarding the impacts of the pandemic on the SDGs, diverse collaborative studies at the regional and global levels are recommended.

19.
Chemosphere ; 300: 134622, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35439491

RESUMEN

Over more than three decades, the scientific community has been contentiously interested in structuring varying photocatalytic materials with unique properties for appropriate technology transfer. Most of the existing reported photocatalysts in the literature show pros and cons by considering the type of application and working conditions. Bismuth titanate oxides (BTO) are novel photocatalysts that raised recently towards energy and environmental-related applications. Most recent advances to developing bismuth titanate-based photocatalysts for the oxidation of organic pollutants in the water phase were reviewed in this report. To counter the potential drawbacks of BTO materials, i.e., rapid recombination of photoproduced charges, and further promote the photoactivity, most reported approaches were discussed, including creating direct Z-scheme junctions, conventional heterojunctions, metal/non-metal doping, coupling with carbon materials, surface modification and construction of oxygen vacancies. In the end, the review addresses the future trends for better engineering and application of BTO based photocatalysts towards the photodegradation of organic pollutants in water under controlled lab and large scales conditions.


Asunto(s)
Contaminantes Ambientales , Agua , Bismuto , Catálisis , Titanio
20.
Front Chem ; 10: 1063288, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36578353

RESUMEN

Photocatalytic hydrogen generation from direct water splitting is recognized as a progressive and renewable energy producer. The secret to understanding this phenomenon is discovering an efficient photocatalyst that preferably uses sunlight energy. Two-dimensional (2D) graphitic carbon nitride (g-C3N4)-based materials are promising for photocatalytic water splitting due to special characteristics such as appropriate band gap, visible light active, ultra-high specific surface area, and abundantly exposed active sites. However, the inadequate photocatalytic activity of pure 2D layered g-C3N4-based materials is a massive challenge due to the quick recombination between photogenerated holes and electrons. Creating 2D heterogeneous photocatalysts is a cost-effective strategy for clean and renewable hydrogen production on a larger scale. The 2D g-C3N4-based heterostructure with the combined merits of each 2D component, which facilitate the rapid charge separation through the heterojunction effect on photocatalyst, has been evidenced to be very effective in enhancing the photocatalytic performance. To further improve the photocatalytic efficiency, the development of novel 2D g-C3N4-based heterostructure photocatalysts is critical. This mini-review covers the fundamental concepts, recent advancements, and applications in photocatalytic hydrogen production. Furthermore, the challenges and perspectives on 2D g-C3N4-based heterostructure photocatalysts demonstrate the future direction toward sustainability.

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