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1.
Heliyon ; 10(8): e29818, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681603

RESUMO

Environmental consciousness motivates scientists to devise an alternative method for producing natural fiber composite materials in order to decrease the demand for synthetic fibers. This study explores the potential of a novel composite material derived from madar fiber-reinforced epoxy with porcelain filler particulates, designed specifically for biomedical instrumentation applications. The primary focus is to assess the material's structural, mechanical, and antibacterial properties. X-ray Diffraction analysis was employed to discern the crystalline nature of the composite, revealing enhanced crystallinity due to the inclusion of porcelain particulates. Fourier-Transform Infrared Spectroscopy confirmed the chemical interactions and bonding mechanisms between madar fiber, epoxy matrix, and porcelain filler. Mechanically, the composite exhibited superior properties when addition of porcelain fillers, maximum results obtain in tensile strength of 51.28 MPa, flexural strength of 54.21 MPa, and impact strength of 0.0155 kJ/m2, making it ideal for robust biomedical applications. Scanning Electron Microscopy provided detailed insights into the morphology and distribution of the reinforcing agents within the epoxy matrix, emphasizing the fibrillated structure of madar fiber and the uniform dispersion of porcelain particulates. Importantly, antibacterial assays demonstrated the composite's potential resistance against common pathogenic bacteria, which is crucial for biomedical instrumentation. Collectively, this research underscores the promising attributes of the madar fiber reinforced epoxy composite with porcelain particulates, suggesting its suitability for advanced biomedical applications.

2.
Bioprocess Biosyst Eng ; 46(3): 309-321, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35301580

RESUMO

Microplastics (MPs) in environmental studies have revealed that public sewage treatment plants are a common pathway for microplastics to reach local surroundings. Microplastics are becoming more of a worry, posing a danger to both marine wildlife and humans. These plastic items not only contribute to the macrocosmic proliferation of plastics but also the scattering of microplastics and the concentration of other micropollutant-containing objects, increasing the number of pollutants identified. Microplastics' behavior, movement, transformation, and persistence mechanisms, as well as their mode of action in various wastewater effluent treatment procedures, are still unknown. They are making microplastics made from wastewater a big deal. We know that microplastics enter wastewater treatment facilities (WWTPs), that wastewater is released into the atmosphere, and that this wastewater has been considered to represent a threat to habitats and ground character based on our literature assessment. The basic methods of wastewater and sewage sludge, as well as the treatment procedure and early characterization, are covered throughout the dissection of the problematic scientific conceptualization.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Humanos , Microplásticos , Plásticos , Esgotos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Eliminação de Resíduos Líquidos
3.
Oxid Med Cell Longev ; 2022: 3088827, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36120599

RESUMO

A simple, efficient, and ecofriendly method was employed to synthesize TiO2/ZrO2/SiO2 ternary nanocomposites using Prunus × yedoensis leaf extract (PYLE) that shows improved photocatalytic and antibacterial properties. The characterization of the obtained nanocomposites was done by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopic (EDS) analysis. The synthesized ternary nanocomposites with nanoscale pore diameters were investigated for the elimination of Reactive Red 120 (RR120) dye. The obtained results showed about 96.2% removal of RR120 dye from aqueous solution under sunlight irradiation. Furthermore, it shows promising antibacterial activity against Staphylococcus aureus and Escherichia coli. The improved photocatalytic and antibacterial activity of TiO2/ZrO2/SiO2 may bring unique insights into the production of ternary nanocomposites and their applications in the environment and biomedical field.


Assuntos
Nanocompostos , Prunus , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Nanocompostos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Dióxido de Silício/química , Titânio
4.
Nanomaterials (Basel) ; 12(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014624

RESUMO

The aqueous extract of Alternanthera sessilis (As) acts as the precursors for the quick reduction of silver ions, which leads to the formation of silver nanoparticles. In the agar, well diffusion method of the Klebsiella pneumoniae shows the minimal inhibitory concentration of 12 mm against A. sessilis mediated silver nanoparticles (As-AgNPs) at 60 µg/mL concentration. Fabric treated with novel AS-AgNPs is tested against the K. pneumoniae and shows an inhibitory action of 12 mm with mixed cotton that determines the antimicrobial efficacy of the fabrics. Uv- visible spectrophotometer was performed, showing a surface plasmon resonance peak at 450 nm cm-1. FTIR shows the vibration and the infrared radiation at a specific wavelength of 500-4000 cm-1. The HR-TEM analysis showed the presence of black-white crystalline, spherical-shaped As-AgNPs embedded on the fabrics range of 15 nm-40 nm. In the scanning electron microscope, the presence of small ball-shaped As-AgNPs embedded on the fabrics at a voltage of 30 KV was found with a magnification of 578X. EDAX was performed in which the nanoparticles show a peak of 2.6-3.9 KeV, and it also reveals the presence of the composition, distribution, and elemental mapping of the nanoparticles. The cytotoxic activity of synthesized nanosilver was carried out against L929 cell lines, which show cell viability at a concentration of 2.5 µg mL-1. Cell proliferation assay shows no cytotoxicity against L929 cell lines for 24 h. In this study, the green synthesis of silver nanoparticles from A. sessilis appears to be a cheap, eco-friendly, and alternative approach for curing infectious ulcers on the floor of the stratum corneum. Nanotechnology conjoined with herbal therapeutics provides a promising solution for wound management.

5.
Biomed Res Int ; 2022: 9223400, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35722463

RESUMO

A technique to predict crucial clinical prostate cancer (PC) is desperately required to prevent diagnostic errors and overdiagnosis. To create a multimodal model that incorporates long-established messenger RNA (mRNA) indicators and conventional risk variables for identifying individuals with severe PC on prostatic biopsies. Urinary has gathered for mRNA analysis following a DRE and before a prostatic examination in two prospective multimodal investigations. A first group (n = 489) generated the multimodal risk score, which was then medically verified in a second group (n = 283). The reverse transcription qualitative polymerase chain reaction determined the mRNA phase. Logistic regression was applied to predict risk in patients and incorporate health risks. The area under the curve (AUC) was used to compare models, and clinical efficacy was assessed by using a DCA. The amounts of sixth homeobox clustering and first distal-less homeobox mRNA have been strongly predictive of high-grade PC detection. In the control subjects, the multimodal method achieved a total AUC of 0.90, with the most important aspects being the messenger riboneuclic acid features' PSA densities and previous cancer-negative tests as a nonsignificant design ability to contribute to PSA, aging, and background. An AUC of 0.86 was observed for one more model that added DRE as an extra risk component. Two methods were satisfactorily verified without any significant changes within the area under the curve in the validation group. DCA showed a massive net advantage and the highest decrease in inappropriate costs.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Biópsia , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA Mensageiro/genética , Fatores de Risco
6.
Bioinorg Chem Appl ; 2022: 7773185, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35655859

RESUMO

Aluminum, magnesium, and copper materials must have increased mechanical strength with enhanced wear and corrosion resistance. Substantial research focused on reinforcing hard particles into low-strength materials using stir casting or powder metallurgy. This work is intended to develop the magnesium hybrid matrix with the dispersion of boron carbide (B4C) and multiwall carbon nanotubes (MWCNTs). Hybrid magnesium composites are prepared, although the powder metallurgy route considers different process parameters. Statistical analysis such as Taguchi L16 orthogonal array is involved in this work. It is used to find the magnesium hybrid samples' minimum and maximum wear, corrosion, and microhardness levels. Powder metallurgy parameters are B4C (3%, 6%, 9%, and 12%), MWCNT (0.2%, 0.4%, 0.6%, and 0.8%), ball milling (1, 2, 3, and 4 h), and sintering (3, 4, 5, and 6 h). The ball milling parameters are extremely influenced in the wear test analysis. Minimum wear losses are obtained as 0.008 g by influencing the 4 h ball milling process. Similarly, 3 h of sintering time offered a minimum corrosion rate of 0.00078 mm/yr. In microhardness analysis, the percentage of MWCNTs is highly implicated in narrow hardness resulting in the hardness value of 181. The hardness value is recorded using 0.2% MWCNTs in the magnesium alloy AZ80.

7.
Bioinorg Chem Appl ; 2022: 6557817, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35154295

RESUMO

Clean technology-based natural fiber composite fabrication is the prime aim of this piece of research. Natural fibers highly replace metal usage in industries and automobile, marine, medical applications, and so on. Vast amounts of natural fibers are freely available in all areas. In this research, work nanofiller material such as nano form waste coir fiber is collected from used car seat. The 10 wt.% of nanofiller material is added to the preparation of natural nanocomposites (ramie and abaca fiber). Hybrid composites are fabricated with the influence of different process parameters, namely, fiber weight percentage (20 wt.%, 30 wt.%, 40 wt.%, and 50 wt.%), NaOH action % (4%, 6%, 8%, and 10%), compression pressure (9 MPa, 12 MPa, 15 MPa, and 18 MPa), and temperature (100°C, 120°C, 140°C, and 160°C). Furthermore, the strength of this hybrid composite has analyzed by conducting flexural, impact, and shore hardness tests. These tests have provided the influence of selected parameters and their effects on the results of experimental work. In the flexural analysis, 6% of NaOH action has offered maximum flexural strength of the specimens. Correspondingly in the impact test, 30 wt.% of fiber is produced higher impact strength. Finally, applying 15 Mpa of compression pressure records the maximum shore hardness.

8.
Bioinorg Chem Appl ; 2022: 8559402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35140762

RESUMO

In the current research, AA6082 aluminium alloy matrix composites (AAMCs) incorporated with various weight fractions of titanium diboride (0, 3, 6, and 9 wt%) were prepared via an in situ casting technique. The exothermic reaction between inorganic powders like dipotassium hexafluorotitanate (K2TiF6) and potassium tetrafluoroborate (KBF4) in molten Al metal contributes to the development of titanium diboride content. The manufactured AA6082-TiB2 AAMCs were evaluated using a scanning electron microscope (SEM) and X-ray diffraction (XRD). The mechanical properties and wear rate (WR) of the AAMCs were investigated. XRD guarantees the creation of TiB2 phases and proves the nonappearance of reaction products in the AMCs. SEM studies depict the even dispersion of TiB2 in the matrix alloy. The mechanical and tribological properties (MTP) of the AAMCs showed improvement by the dispersion of TiB2 particles. The WR decreases steadily with TiB2 and the least WR is seen at nine weight concentrations of TiB2/AA6082 AAMCs. Fabricated composites revealed 47.9% higher flexural strength and 14.2% superior compression strength than the base AA6082 alloy.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35082906

RESUMO

The CLEC-2 receptor protein belongs to the C-type lectin superfamily of transmembrane receptors that have one or more C-type lectin-like domains. CLEC-2 is a physiological binding receptor of podoplanin (PDPN), which is expressed on specific tumour cell types and involved in tumour cell-induced platelet aggregation and tumour metastasis. CLEC-2 and podoplanin-expressing tumour cells interact to increase angiogenesis, tumour development, and metastasis. CLEC-2 is a hemi-immunoreceptor tyrosine-based activation motif (hemi-ITAM) receptor located on platelets and a subset of dendritic cells that are expressed constitutively. This molecule is secreted by activated platelets around tumours and has been shown to inhibit platelet aggregation and tumour metastasis in colon carcinoma by binding to the surface of tumour cells. Pharmacokinetic studies were carried using a DrugLiTo, and molecular docking was performed using AutoDock Tools 1.5.6 (ADT). Twenty-nine bioactive compounds were included in the study, and four of them, namely, piperine, dihydrocurcumin, bisdemethoxycurcumin, and demothoxycurcumin, showed potential antagonist properties against the target. The resultant best bioactive was compared with commercially available standard drugs. Further, validation of respective compounds with an intensive molecular dynamics simulation was performed using Schrödinger software. To the best of our knowledge, this is the first report on major bioactive found on clove as natural antagonists for CLEC-2 computationally. To further validate the bioactive and delimit the screening process of potential drugs against CLEC-2, in vitro and in vivo studies are needed to prove their efficacy.

10.
Environ Sci Pollut Res Int ; 29(7): 10173-10182, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34515934

RESUMO

The solar photovoltaic system is an emerging renewable energy resource. The performance of the solar photovoltaic system is predicted based on the historical experimental dataset. In this work, the real-time prediction models are developed for the output power prediction of the STPV system. The performance of the semitransparent photovoltaic system is predicted for the Kovilpatti region where the climatic condition is hot and humid. The short-term power is predicted for the hourly, daily, and weekly average are considered. The feature selected for the prediction of the output power of the STPV system comprises of the solar radiation, ambient temperature, and wind velocity of the Kovilpatti region. The result reveals that the output power prediction of the hourly, daily, and weekly power have the very high value of the correlation coefficient of R. The final model produced accurate forecasts, with a Root mean square (RMSE) of 0.25 in ELMAN and 0.30 in FFN and 0.426 in GRN. These features of the training algorithm indicate that the model is not dependent on the model's position or configuration in the simulation.


Assuntos
Redes Neurais de Computação , Energia Solar , Simulação por Computador , Energia Renovável , Vento
11.
Environ Sci Pollut Res Int ; 29(7): 9491-9532, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34854004

RESUMO

The energy storage application plays a vital role in the utilization of the solar energy technologies. There are various types of the energy storage applications are available in the todays world. Phase change materials (PCMs) are suitable for various solar energy systems for prolonged heat energy retaining, as solar radiation is sporadic. This literature review presents the application of the PCM in solar thermal power plants, solar desalination, solar cooker, solar air heater, and solar water heater. Even though the availability and cost of PCMs are complex and high, the PCMs are used in most solar energy methods due to their significant technical parameters improvisation. This review's detailed findings paved the way for future recommendations and methods for the investigators to carry work for further system developments.


Assuntos
Energia Solar , Temperatura Alta , Luz Solar , Água
12.
Polymers (Basel) ; 13(23)2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34883698

RESUMO

In recent days, natural fibers are extremely influential in numerous applications such as automobile body building, boat construction, civil structure, and packing goods. Intensification of the properties of natural fibers is achieved by blending different natural fibers with resin in a proper mixing ratio. This investigation aims to synthesize a hybrid polymer matrix composite with the use of natural fibers of flax and loops of hemp in the epoxy matrix. The synthesized composites were characterized in terms of tribological and mechanical properties. The Taguchi L16 orthogonal array is employed in the preparation of composite samples as well as analysis and optimization of the synthesis parameters. The optimization of compression molding process parameters has enhanced the results of this investigation. The parameters chosen are percentage of reinforcement (20%, 30%, 40%, and 50%), molding temperature (150 °C, 160 °C, 170 °C, and 180 °C), molding pressure (1 MPa, 2 MPa, 3 MPa, and 4 MPa), and curing time (20 min, 25 min, 30 min, and 35 min). From the analysis, it was observed that the percentage of reinforcement is contributing more to altering the fatigue strength, and the curing time is influenced in the impact and wear analysis.

13.
Polymers (Basel) ; 13(22)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34833158

RESUMO

Awareness of environmental concerns influences researchers to develop an alternative method of developing natural fiber composite materials, to reduce the consumption of synthetic fibers. This research attempted testing the neem (Azadirachta indica) fiber and the banyan (Ficus benghalensis) fiber at different weight fractions, under flame retardant and thermal testing, in the interest of manufacturing efficient products and parts in real-time applications. The hybrid composite consists of 25% fiber reinforcement, 70% matrix material, and 5% bran filler. Their thermal properties-short-term heat deflection, temperature, thermal conductivity, and thermal expansion-were used to quantify the effect of potential epoxy composites. Although natural composite materials are widely utilized, their uses are limited since many of them are combustible. As a result, there has been a lot of focus on making them flame resistant. The thermal analysis revealed the sample B was given 26% more short-term heat resistance when the presence of banyan fiber loading is maximum. The maximum heat deflection temperature occurred in sample A (104.5 °C) and sample B (99.2 °C), which shows a 36% greater thermal expansion compared with chopped neem fiber loading. In sample F, an increased chopped neem fiber weight fraction gave a 40% higher thermal conductivity, when compared to increasing the bidirectional banyan mat of this hybrid composite. The maximum flame retardant capacity occurred in samples A and B, with endurance up to 12.9 and 11.8 min during the flame test of the hybrid composites.

14.
Materials (Basel) ; 14(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576481

RESUMO

Two-body abrasive wear behavior of glass fabric reinforced (GC) epoxy and titanium dioxide (TiO2) filled composites have been conducted out by using a tribo test machine. GC and TiO2 filled GC composites were produced by the hand layup technique. The mechanical performances of the fabricated composites were calculated as per ASTM standards. Three different weight percentages were mixed with the polymer to develop the mechanical and abrasive wear features of the composites. Evaluation Based on Distance from Average Solution (EDAS), a multi-criteria decision technique is applied to find the best filler content. Based on the output, 2wt% TiO2 filler gave the best result. Abrasive wear tests were used to compare GC and TiO2 filled GC composites. The abrasion wear mechanisms of the unfilled and TiO2 filled composites have also been studied by scanning electron microscopy. The outcome of the paper suggests the correct proportion of filler required for the resin in order to improve the wear resistance of the filled composites. Taguchi combined with Multi-Criteria Decision Method (MCDM) is used to identify the better performance of the TiO2 filled epoxy composites.

15.
Materials (Basel) ; 14(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361508

RESUMO

In this paper, Al-Fe-Si-Zn-Cu (AA8079) matrix composites with several weight percentages of B4C (0, 5, 10, and 15) were synthesized by powder metallurgy (PM). The essential amount of powders was milled to yield different compositions such as AA8079, AA8079-5 wt.%B4C, AA8079-10 wt.%B4C, and AA8079-15 wt.%B4C. The influence of powder metallurgy parameters on properties' density, hardness, and compressive strength was examined. The green compacts were produced at three various pressures: 300 MPa, 400 MPa, and 500 MPa. The fabricated green compacts were sintered at 375 °C, 475 °C, and 575 °C for the time period of 1, 2 and 3 h, respectively. Furthermore, the sintered samples were subjected to X-ray diffraction (XRD) analysis, Energy Dispersive Analysis (EDAX), and Scanning Electron Microscope (SEM) examinations. The SEM examination confirmed the uniform dispersal of B4C reinforcement with AA8079 matrix. Corrosion behavior of the composites samples was explored. From the studies, it is witnessed that the rise in PM process parameters enhances the density, hardness, compressive strength, and corrosion resistance.

16.
Materials (Basel) ; 14(11)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198918

RESUMO

This study focuses on the properties and process parameters dictating behavioural aspects of friction stir welded Aluminium Alloy AA6061 metal matrix composites reinforced with varying percentages of SiC and B4C. The joint properties in terms of mechanical strength, microstructural integrity and quality were examined. The weld reveals grain refinement and uniform distribution of reinforced particles in the joint region leading to improved strength compared to other joints of varying base material compositions. The tensile properties of the friction stir welded Al-MMCs improved after reinforcement with SiC and B4C. The maximum ultimate tensile stress was around 172.8 ± 1.9 MPa for composite with 10% SiC and 3% B4C reinforcement. The percentage elongation decreased as the percentage of SiC decreases and B4C increases. The hardness of the Al-MMCs improved considerably by adding reinforcement and subsequent thermal action during the FSW process, indicating an optimal increase as it eliminates brittleness. It was seen that higher SiC content contributes to higher strength, improved wear properties and hardness. The wear rate was as high as 12 ± 0.9 g/s for 10% SiC reinforcement and 30 N load. The wear rate reduced for lower values of load and increased with B4C reinforcement. The microstructural examination at the joints reveals the flow of plasticized metal from advancing to the retreating side. The formation of onion rings in the weld zone was due to the cylindrical FSW rotating tool material impression during the stirring action. Alterations in chemical properties are negligible, thereby retaining the original characteristics of the materials post welding. No major cracks or pores were observed during the non-destructive testing process that established good quality of the weld. The results are indicated improvement in mechanical and microstructural properties of the weld.

17.
Materials (Basel) ; 14(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34279259

RESUMO

Wire Cut Electric Discharge Machining (WCEDM) is a novel method for machining different materials with application of electrical energy by the movement of wire electrode. For this work, an AZ61 magnesium alloy with reinforcement of boron carbide and silicon carbide in different percentage levels was used and a plate was formed through stir casting technique. The process parameters of the stir casting process are namely reinforcement %, stirring speed, time of stirring, and process temperature. The specimens were removed from the casted AZ61 magnesium alloy composites through the Wire Cut Electric Discharge Machining (WCEDM) process, the material removal rate and surface roughness vales were carried out creatively. L 16 orthogonal array (OA) was used for this work to find the material removal rate (MRR) and surface roughness. The process parameters of WCEDM are pulse on time (105, 110, 115 and 120 µs), pulse off time (40, 50, 60 and 70 µs), wire feed rate (2, 4, 6 and 8 m/min), and current (3, 6, 9 and 12 Amps). Further, this study aimed to estimate the maximum ultimate tensile strength and micro hardness of the reinforced composites using the Taguchi route.

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