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1.
Sci Total Environ ; 929: 172189, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38583624

RESUMO

This study explores the incorporation of Nb2AlC and Mo3AlC2 MAX phases, known for their nano-layered structure, into polyether sulfone (PES) membranes to enhance their antifouling and permeability properties for pathogen microorganism filtration against bovine serum albumin (BSA) and Escherichia coli (E. coli). The composite membranes were characterized for their structural and morphological properties, and their performance in mitigating biofouling was evaluated. The structural characterizations have been performed for all the prepared MAX phases and corresponding composite membranes. The antioxidant ability of Nb2AlC and Mo3AlC2 MAX phases was defined by the DPPH radical scavenging assay, and the highest antioxidant ability was found to be 59.35 %, while 53.69 % scavenging potential was recorded at 100 mg/L. The percentage scavenging ability was raised with an increase in concentrations. The antimicrobial properties of MAX phases, evaluated as the minimum inhibitory concentration, were stated against several pathogen microorganisms. The tested compounds of Nb2AlC and Mo3AlC2 composites containing MAX phases exhibited excellent chemical nuclease activity, and it was determined that Nb2AlC caused double strand DNA cleavage activity while Mo3AlC2 induced the complete fragmentation of the DNA molecule. Biofilm inhibition of Nb2AlC and Mo3AlC2 MAX phases was studied against Staphylococcus aureus, and Pseudomonas aeruginosa and the maximum biofilm inhibition of Nb2AlC and Mo3AlC2 MAX phases was found to be 77.15 % and 69.07 % against S. aureus and also 69.74 % and 65.01 % against P. aeruginosa. Furthermore, Nb2AlC and Mo3AlC2 MAX phases demonstrated excellent E. coli growth inhibition of 100 % at 125 and 250 mg/L.


Assuntos
Incrustação Biológica , Escherichia coli , Membranas Artificiais , Polímeros , Sulfonas , Incrustação Biológica/prevenção & controle , Sulfonas/farmacologia , Sulfonas/química , Polímeros/farmacologia , Escherichia coli/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Filtração
2.
Int J Biol Macromol ; 261(Pt 1): 129146, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38176489

RESUMO

The study explores the synergy of biobased polymers and hydrogels for water purification. Polymer nanomaterial's, synthesized by combining acrylamide copolymer with maleic anhydride, were integrated into sodium alginate biopolymer using an eco-friendly approach. Crosslinking agents, calcium chloride and glutaraladehyde, facilitated seamless integration, ensuring non-toxicity, high adsorption performance, and controlled capacity. This innovative combination presents a promising solution for clean and healthy water supplies, addressing the critical need for sustainable environmental practices in water purification. In addition, the polymer sodium alginate hydrogel (MAH@AA-P/SA/H) underwent characterization via the use of several analytical procedures, such as FTIR, XPS, SEM, EDX and XRD. Adsorption studies were conducted on metals and dyes in water, and pollutant removal methods were explored. We investigated several variables (such as pH, starting concentration, duration, and absorbent quantity) affect a material's capacity to be adsorbed. Moreover, the maximum adsorption towards Cu2+ is 754 mg/g while for Cr6+ metal ions are 738 mg/g, while the adsorption towards Congo Red and Methylene Blue dye are 685 mg/g and 653 mg/g correspondingly, within 240 min. Adsorption results were further analyzed using kinetic and isothermal models, which showed that MAH@AA-P/SA/H adsorption is governed by a chemisorption process. Hence, the polymer prepared from sodium alginate hydrogel (MAH@AA-P/SA/H) has remarkable properties as a versatile material for the significantly elimination of harmful contaminants from dirty water.


Assuntos
Hidrogéis , Poluentes Químicos da Água , Hidrogéis/química , Anidridos Maleicos , Corantes/química , Alginatos/química , Acrilamida , Metais , Íons , Polímeros , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética
3.
Int J Biol Macromol ; 254(Pt 2): 127153, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37778574

RESUMO

Clean and safe water resources are essential for environmental safety and human health. Hydrogels and biomass polymers have attracted considerable attention in recent years, considering their nontoxicity, controllable performance, and high adsorption capacity. The interpenetrating network described here is a combination of a biomass polymer and a hydrogel adsorbent was established, the biomass polymer microspheres were first prepared with the combination of biomass monomer trans-anethole and maleic anhydride copolymer. A simple, environmentally friendly, and facile method of incorporating biomass polymer into sodium alginate biopolymer was developed by introducing the cross-linking agents calcium chloride and glutaraldehyde into the biomass polymer. Furthermore, the biomass polymer sodium alginate hydrogel (BP@SA/H) was characterized by FTIR, XPS, SEM, and XRD. In order to test materials' performance, the removal of pollutants and the adsorption study were also investigated after and before adsorption toward metals and dyes in water. We examined the factors influencing the materials, adsorption capability, such as initial concentration, time, absorbent amount, and pH. Moreover, the maximum adsorption values for Pb+2 and Cd+2 were 734.9 and 722 mg/g. While the adsorption toward RhB dye are 745 mg/g. In addition, the adsorption results were investigated using kinetic and isothermal models, demonstrating that biomass polymer hydrogel adsorption is chemisorption. Therefore, the as-developed biomass polymer sodium alginate hydrogel (BP@SA/H) is an exceptional multifunctional material that can be used to remove hazardous pollutants from wastewater.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Humanos , Águas Residuárias , Corantes/química , Polímeros/química , Hidrogéis/química , Alginatos/química , Metais , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Cinética
4.
Molecules ; 28(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36985660

RESUMO

In this study, various techniques, including X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS) mapping, X-ray photoelectron spectroscopy (XPS), and water-contact-angle goniometry (WCAG), were used to characterize the crystalline structure and morphological properties of terbium-doped cerium magnesium aluminate (Ce0.67Tb0.33MgAl11O19 or CMAT) in powder form. The results demonstrated that CMAT was successfully synthesized with a particle size of less than 5 µm and a fully evident distribution of elements, as revealed by the SEM images. This was further confirmed by the XRD and HRTEM images. XPS analysis confirmed the presence of all necessary components in CMAT. Additionally, WCAG results showed that the contact angle of CMAT was more hydrophilic with a value of 8.4°. To evaluate its performance, CMAT particles were dispersed in a Polyethersulfone (PES) solution and used to modify a PES ultrafiltration membrane through a phase-inversion method. The resulting membranes were characterized by SEM, atomic force microscopy (AFM), thermogravimetric analysis (TGA), WCAG, and permeability performance and fouling experiments. The addition of CMAT to the PES membranes did not have a significant effect on the structure of the SEM images of the top layer and cross-section of surface properties. However, increasing the concentration of CMAT improved the membrane surface roughness in AFM, and the modified membranes had the ability to resist fouling. The addition of CMAT did not lead to significant energy loss, indicating that the heat flux loss observed can indeed be explained by the amount of C-OH on the PES membrane's surface. The contact angle of the membranes became more hydrophilic with increasing concentration of CMAT from PES G0 to PES G7. The PES origin membrane showed a higher permeation than the membranes mixed with CMAT, and the modified membranes with CMAT displayed significant fouling resistance.

5.
Environ Res ; 221: 115213, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36610540

RESUMO

A special type of two-dimensional (2D) material based conducting polymer was constructed by green synthesis and in-situ polymerization techniques. The 2D Molybdenum Disulfide (MoS2) were first synthesized with the combination of, ammonium tetrathiomolybdate dissolved in 20 mL algae extract under stirring. After stirring for about 2 h, and then finally sulfurization was initiated using sulfur powder in 20 mL of sulfuric solution and stirred for 8 h. The resulting black precipitates of MoS2 were collected by centrifugation at 5000 rpm. Moreover, the prepared MoS2 was functionalized with glycidyl methacrylate (GMA) and form the MoS2@PGMA. Further, the MoS2@PGMA is combined with polyaniline (PANI) to form conducting polymer grafted thin film nanosheets named MoS2@PGMA/PANI with a thickness in micrometer size through grafting method. The prepared materials were characterized by SEM, FTIR, XRD, XPS and EDX techniques. To check the performance of materials the adsorption study was performed. Moreover, the adsorption study toward Cu2+ and Cd2+ showed a tremendous results and the maximum adsorption was 307.7 mg/g and 214.7 mg/g respectively. In addition, the pseudo-first and second order models as well as the adsorption isotherm were investigated using the Langmuir and Freundlich model. The results were best fitted with the pseudo-second order and Langmuir models. The regeneration study was also conducted and MoS2@PGMA/PANI nanosheets can be easily recycled and restored after five successful recycling. The established methodology for preparing the 2D materials and conducting polymer based MoS2@PGMA/PANI nanosheets is expected to be applicable for other multiple applications.


Assuntos
Molibdênio , Águas Residuárias , Metais , Polímeros , Íons
6.
Environ Res ; 220: 115135, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36566962

RESUMO

The greatest environmental issue of the twenty-first century is climate change. Human-caused greenhouse gas emissions are increasing the frequency of extreme weather. Carbon dioxide (CO2) accounts for 80% of human greenhouse gas emissions. However, CO2 emissions and global temperature have risen steadily from pre-industrial times. Emissions data are crucial for most carbon emission policymaking and goal-setting. Sustainable and carbon-neutral sources must be used to create green energy and fossil-based alternatives to reduce our reliance on fossil fuels. Near-real-time monitoring of carbon emissions is a critical national concern and cutting-edge science. This review article provides an overview of the many carbon accounting systems that are now in use and are based on an annual time frame. The primary emphasis of the study is on the recently created carbon emission and eliminating sources and technology, as well as the current application trends for carbon neutrality. We also propose a framework for the most advanced naturally available carbon neutral accounting sources capable of being implemented on a large scale. Forming relevant data and procedures will help the "carbon neutrality" plan decision-making process. The formation of pertinent data and methodologies will give robust database support to the decision-making process for the "carbon neutrality" plan for the globe. In conclusion, this article offers some opinions, opportunities, challenges and future perspectives related to carbon neutrality and carbon emission monitoring and eliminating resources and technologies.


Assuntos
Dióxido de Carbono , Gases de Efeito Estufa , Humanos , Dióxido de Carbono/análise , Efeito Estufa , Biodiversidade , Temperatura , Tecnologia , Recursos Naturais
7.
Environ Res ; 219: 114998, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36481367

RESUMO

BACKGROUND: An efficient solution to the global freshwater dilemma is desalination. MXene, Molybdenum Disulfide (MoS2), Graphene Oxide, Hexagonal Boron Nitride, and Phosphorene are just a few examples of two-dimensional (2D) materials that have shown considerable promise in the development of 2D materials for water desalination. However, other promising materials for desalinating water are biomaterials. The benefits of bio-materials are their wide distribution, lack of toxicity, and superior capacity for water desalination. METHODS: For the rational use of water and the advancement of sustainable development, it is of the utmost importance to research 2D-dimensional materials and biomaterials that are effective for water desalination. The scientific community has concentrated on wastewater remediation using bio-derived materials, such as nanocellulose, chitosan, bio-char, bark, and activated charcoal generated from plant sources, among the various endeavors to enhance access to clean water. Moreover, the 2D-materials and biomaterials may have ushered in a new age in the production of desalination materials and created a promising future. RESULTS: The present review article focuses on and reviews the progress of 2D materials and biomaterials for water desalination. Their properties, surface, and structure, combined with water desalination applications, are highlighted. Further, the practicability and potential future directions of 2D materials and biomaterials are proposed. Thus, the current work provides information and discernments for developing novel 2D materials and biomaterials for wastewater desalination. Moreover, it aims to promote the contribution and advancement of materials for water desalination, fabrication, and industrial production.


Assuntos
Quitosana , Água , Águas Residuárias , Materiais Biocompatíveis
8.
Chemosphere ; 267: 128871, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33308836

RESUMO

Despite the huge contribution of membrane-based brine and wastewater purification systems in today's life, biofouling still affects sustainability of membrane engineering. Aimed at reducing membrane modules wastage, the need to study biofouling monitoring as one of contributory factors stemmed from the short time between initial attachment and irreversible biofoulant adhesion. Hence, a membrane for monitoring is introduced to determine the right cleaning time by using fluorescent sensing as a non-destructive and scalable approach. The classical solid-state emissive fluorophore, tetraphenylethylene (TPE), was introduced as a sustainable, safe and sensitive fluorescent indicator in order to show the potential of the method, and polyethersulfone (PES) and nonsolvent-induced phase separation method, the most popular material and method, are used to fabricate membrane in industry and academia. Since the employed filler has an aggregation-induced emission (AIE) characteristic, it can track the biofouling throughout the operation. The fabricated membranes have certain characterizations (i.e. morphology assessment, flux, antibiogram, flow cytometry, surface free energy, and protein adsorption) which indicate that hybrid membrane with 5 wt % of TPE has identical biofouling activity compared to neat PES membrane and its optimal luminescence properties make it an appropriate candidate for non-destructive and online biofouling monitoring.


Assuntos
Incrustação Biológica , Purificação da Água , Luminescência , Membranas Artificiais , Polímeros , Estilbenos , Sulfonas , Ultrafiltração
9.
Molecules ; 24(16)2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31409035

RESUMO

There have been developments in the optimization of polyether sulfone (PES) membranes, to provide antifouling and mechanically stable surfaces which are vital to water purification applications. There is a variety of approaches to prepare nanocomposite PES membranes. However, an optimized condition for making such membranes is in high demand. Using experimental design and statistical analysis (one-half fractional factorial design), this study investigates the effect of different parameters featured in the fabrication of membranes, as well as on the performance of a nanocomposite PES/TiO2 membrane. The optimized parameters obtained in this study are: exposure time of 60 s, immersion time above 10 h, glycerol time of 4 h, and a nonsolvent volumetric ratio (isopropanol/water) of 30/70 for PES and dimethylacetamide (PES-DMAc) membrane and 70/30 for PES and N-methyl-2-pyrrolidone (PES-NMP) membrane. A comparison of the contributory factors for different templating agents along with a nanocomposite membrane control, revealed that F127 triblock copolymer resulted in an excellent antifouling membrane with a higher bovine serum albumin rejection and flux recovery of 83.33%.


Assuntos
Nanocompostos/química , Polímeros/química , Sulfonas/química , Titânio/química , 2-Propanol/química , Acetamidas/química , Análise Fatorial , Glicerol/química , Humanos , Membranas Artificiais , Nanocompostos/ultraestrutura , Pirrolidinonas/química , Soroalbumina Bovina/química , Água/química , Purificação da Água/métodos
10.
Heliyon ; 5(5): e01754, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31193508

RESUMO

In the present study, the effect of heating methods has been studied on the microstructure and mechanical properties of in-situ formed Al3V-Al-VC nano-composite. 5 and 15 wt % of VC were added to Al matrix and conventional and microwave sintering processes were performed at 600 °C. While spark plasma sintering process was done at 450 °C with initial and final pressure of 10 and 30 MPa, respectively. The XRD results revealed the formation of Al3V intermetallic compound in microwave sintered sample, while in both spark plasma sintered and conventionally prepared specimens, the only crystalline phases were Al and VC. Microstructure studies, demonstrated a uniform distribution of 5wt% VC reinforcement in Al matrix but the 15wt%VC addition led to form agglomerates in all prepared samples. The highest bending strength (275 ± 13 MPa) and hardness (260 ± 13 Vickers) were obtained in the spark plasma sintered sample with 15wt% of VC content.

11.
Materials (Basel) ; 10(11)2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-29088114

RESUMO

In this research, the mechanical properties and microstructure of Al-15 wt % TiC composite samples prepared by spark plasma, microwave, and conventional sintering were investigated. The sintering process was performed by the speak plasma sintering (SPS) technique, microwave and conventional furnaces at 400 °C, 600 °C, and 700 °C, respectively. The results showed that sintered samples by SPS have the highest relative density (99% of theoretical density), bending strength (291 ± 12 MPa), and hardness (253 ± 23 HV). The X-ray diffraction (XRD) investigations showed the formation of TiO2 from the surface layer decomposition of TiC particles. Scanning electron microscopy (SEM) micrographs demonstrated uniform distribution of reinforcement particles in all sintered samples. The SEM/EDS analysis revealed the formation of TiO2 around the porous TiC particles.

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