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1.
Polymers (Basel) ; 16(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38201805

RESUMO

A magnetite chlorodeoxycellulose/ferroferric oxide (CDC@Fe3O4) heterogeneous photocatalyst was synthesised via treated and modified cotton in two steps. The designed nanocomposites were characterised by FTIR, TGA, XRD, SEM, and VSM analyses. The Fenton-photocatalytic decomposition efficiency of the synthesised magnetic catalyst was evaluated under visible sunlight using Methyl Orange (MO) as a model organic pollutant. The impacts of several degradation parameters, including the light source, catalyst load, irradiation temperature, oxidant dose, and pH of the dye aqueous solution and its corresponding concentration on the Fenton photodegradation performance, were methodically investigated. The (CDC@Fe3O4) heterogeneous catalyst showed a remarkable MO removal rate of 97.9% at 10 min under visible-light irradiation. (CDC@Fe3O4) nanomaterials were also used in a heterogeneous catalytic optimised protocol for a multicomponent reaction procedure to obtain nine tetra-substituted imidazole derivatives. The green protocol afforded imidazole derivatives in 30 min with good yields (91-97%) at room temperature and under ultrasound irradiation. Generally, a synthesised recyclable heterogeneous nano-catalyst is a good example and is suitable for wastewater treatment and organic synthesis.

2.
Environ Sci Pollut Res Int ; 30(53): 114525-114534, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37861829

RESUMO

The contamination of saltwater by toxic heavy metals has become a worldwide problem. The application of phytoextraction to remove these pollutants seems to be more efficient and cheaper compared to physicochemical methods. In this work, we evaluated the potential of two halophyte species to accumulate cadmium and zinc from contaminated water. Seedlings of Carpobrotus edulis L. and Sesuvium portulacastrum L. were cultivated during 1 month on pots filled with saltwater (200 mM NaCl) containing different concentrations of Cd2+ (0, 50, 100 µM) and of Zn2+ (0, 200, and 400 µM) applied separately. Results showed that both halophytes were more resistant to Zn2+ than Cd2+ and that Sesuvium better tolerates the two metals. Zn2+ and Cd2+ concentrations in the shoot as well as the values of translocation factors suggest that these species are able to absorb and to concentrate Cd2+ and Zn2+ in their roots and shoots. Hence, after 1 month of culture on 50 µM Cd2+, plants were able to extract 31% and 21% of Cd, respectively, in S. portulacastrum and C. edulis. The Zn-extraction efficiency was less important and reached 18 and 19%, respectively, in S. portulacastrum and C. edulis cultivated under 200 µM Zn2+. Given together, data demonstrate the efficiency of the use of halophytes, especially S. portulacastrum, to extract Zn2+ and Cd2+ from salt wastewater.


Assuntos
Aizoaceae , Poluentes do Solo , Plantas Tolerantes a Sal , Cádmio/toxicidade , Cloreto de Sódio , Zinco , Biodegradação Ambiental
3.
ACS Omega ; 8(35): 32067-32077, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692231

RESUMO

Iron oxide nanoparticles (Fe3O4NPs) are a fascinating field of study due to their wide range of practical applications in environmental and medical contexts. This study presents a straightforward, environmentally friendly method for producing Fe3O4NPs utilizing ß-cyclodextrin (ß-CD) as a reducing and capping agent. This approach results in the rapid and effective eco-friendly synthesis of ß-CD/Fe3O4NPs. The properties and characteristics of ß-CD/Fe3O4NPs were investigated using various methods, including ultraviolet-visible (UV/vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetry analysis (TGA), and vibrating-sample magnetometry (VSM). The absorption of ß-CD/Fe3O4NPs caused a distinct peak at 349 nm, as evidenced by the results of UV/vis studies. This peak was attributed to the absorption of surface plasmon resonance. The crystalline nature of ß-CD/Fe3O4NPs was confirmed through XRD analysis. The SEM and TEM analyses have verified the geometry and structural characteristics of ß-CD/Fe3O4NPs. The ß-CD/Fe3O4NPs exhibited remarkable effectiveness in the decomposing efficiency (%) of methylene blue (MB) dye with 52.2, 94.1, and 100% for 0.2, 0.4, and 0.6 g ß-CD/Fe3O4NPs, respectively. In addition, the highest efficiency in hunting radicals was observed (347.2 ± 8.2 mg/g) at 100 mg/mL ß-CD/Fe3O4NPs; the combination of ß-CD/Fe3O4NPs exhibited remarkable effectiveness in inhibiting the growth of some bacteria that cause infections. The capabilities of ß-CD/Fe3O4NPs for various applications showed that these materials could be used in photocatalytic, antioxidants, and antibacterial. Additionally, the eco-friendly synthesis of these materials makes them a promising option for the remediation of harmful pollutants and microbes.

4.
ACS Omega ; 8(24): 21425-21437, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360427

RESUMO

In order to enhance the efficacy of organic solar cells, six new three-dimensional small donor molecules (IT-SM1 to IT-SM6) have been computationally designed by modifying the peripheral acceptors of the reference molecule (IT-SMR). The frontier molecular orbitals revealed that IT-SM2 to IT-SM5 had a smaller band gap (Egap) than IT-SMR. They also had smaller excitation energies (Ex) and exhibited a bathochromic shift in their absorption maxima (λmax) when compared to IT-SMR. In both the gas and chloroform phases, IT-SM2 had the largest dipole moment. IT-SM2 also had the best electron mobility, while IT-SM6 had the best hole mobility owing to their smallest reorganization energy for electron (0.1127 eV) and hole (0.0907 eV) mobility, respectively. The analyzed donor molecules' open-circuit voltage (VOC) indicated that all of these proposed molecules had greater VOC and fill factor (FF) values than the IT-SMR molecule. In accordance with the evidence of this work, the altered molecules can seem to be quite proficient for usage by experimentalists and have prospective use in future in the manufacture of organic solar cells with improved photovoltaic properties.

5.
Foods ; 11(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36553696

RESUMO

Throughout the vegetable oil industry, there is a focus on eradicating the volatile molecules affecting the aroma or taste of the crude oil, whether it is natural or derived from the extraction process. Refining aims to reduce these compounds to a level acceptable to the consumer. In addition, the famous conventional operation of deodorization calls for high levels of temperature depending on the boiling point used to remove the atmospheric pressure of each molecule. The process implies a vacuum level between 10 to 80 kPa absolute pressure, a temperature generally between 190 and 240 °C, and a duration of 2 to 3 h. These conditions necessarily (inevitably) lead to a decrease in the quality of refined oil. Recently, the application of the Multi-Flash Autovaporization "MFA" operation has shown the possibility of eradicating volatile molecules while adopting relatively low temperature and time levels. Despite the high boiling temperature of the volatile organic compounds (VOC), MFA leads to good efficiency in reducing VOCs and preserving oil quality. The main odorant compounds in the crude palm oil were E-2-Hexenal, heptanal, octanal, nonanal, and decanal. Specific literature can indicate precise boiling temperatures under atmospheric pressure. In addition, many experimental studies have explained the evolution of each molecule and shown how they depend on the operating parameters (inlet oil pressure from 200 to 450 kPa and from 5 and 30 s time of each cycle, and the number of cycles up to 7), and how the empirical mathematical models describe the MFA deodorization, estimate the efficiency of the whole process, and optimize the operating parameters. In this research, the thermodynamic data of absolute pressure volatility versus temperature was used to better identify the removal rate (up to around 87%) implied by an abrupt pressure drop to a vacuum of 5 kPa for p = 450 kPa, t = 25 s/cycle, and the number of cycles (C = 6). The safeguarding of the fatty acid profile illustrated the maintenance of the oil quality.

6.
Nanomaterials (Basel) ; 12(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36296875

RESUMO

The objective of this research was to explore the impact of corrosion inhibition of some synthetic acrylamide derivatives 2-cyano-N-(4-hydroxyphenyl)-3-(4-methoxyphenyl)acrylamide (ACR-2) and 2-cyano-N-(4-hydroxyphenyl)-3-phenylacrylamide (ACR-3) on copper in 1.0 M nitric acid solution using chemical and electrochemical methods, including mass loss as a chemical method and electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP) as electrochemical methods. By Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), and mass spectroscopy (MS) methods, the two compounds were verified and characterized. There is evidence that both compounds were effective corrosion inhibitors for copper in 1.0 M nitric acid (HNO3) solutions, as indicated by the PP curves, which show that these compounds may be considered mixed-type inhibitors. With the two compounds added, the value of the double-layer capacitance was reduced. In the case of 20 × 10-5 M, they reached maximum efficiencies of 84.5% and 86.1%, respectively. Having studied its behavior during adsorption on copper, it was concluded that it follows chemical adsorption and Langmuir isotherm. The theoretical computations and the experimental findings were compared using density functional theory (DFT) and Monte Carlo simulations (MC).

7.
Int J Biol Macromol ; 217: 606-614, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35843402

RESUMO

Vanadium pentoxide has the most exciting oxidation states, but, Vanadium pentoxide (V2O5) has low capacitance due to poor electrical conductivity and ionic diffusivity. So, encapsulating pentoxide in carbonaceous materials or metals, shrinking it to the nanoscale, or changing its morphology can improve capacitance performance. Herein, we describe a green synthesis of V2O5NPs with carboxymethyl cellulose (CMC) that typically acts as a reducing and stabilizing agent using the -COOH and -OH group. The physicochemical characterization of prepared samples reveals the prominent peak in UV-vis spectra at 265 nm confirming the formation of V2O5NPs with particle sizes between 200 and 220 nm. The theoretical surface area for the nanocomposite was 76.5 m2/g. The calcination temperature is essential to determine a material's specific capacitance. Due to decreased oxide agglomeration, the V2O5-green modified electrode exhibits superior electrochemical performance around 223 F g-1 than Ac alone (160 F g-1). The finding demonstrated excellent cyclic stability with reduced fluctuation in capacitance. Because of its exceptional electrochemical performance and simplicity of access, this AC/V2O5 nanocomposite can be helpful as an electrode for energy storage applications.


Assuntos
Carboximetilcelulose Sódica , Nanotubos , Capacitância Elétrica , Eletrodos , Íons/química
8.
Carbohydr Polym ; 286: 119207, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35337492

RESUMO

Ion-imprinting methodology was utilized in the fabrication of mercury ion-imprinted sorbent derived from modified chitosan derivatives. The Schiff base ligand was first derived from 4-amino-3-hydroxybenzoic acid and 2-pyridinecarboxaldehyde (HPB) and then incorporated with chitosan via amide bonds. The obtained modified chitosan polymeric ligand (PBCS) was combined with Hg(II) ions to produce the corresponding polymeric complex and the imprinting was then achieved upon the glutaraldehyde cross-linking and eliminating the incorporated Hg(II) ions to finally have the Hg(II) ion-imprinted sorbent material (Hg-PBCS). The materials have been investigated using various techniques such as NMR and FTIR and the obtained sorbent was examined to evaluate its selective affinity to capture the target Hg(II) ions. The developed Hg-PBCS sorbent exhibited a higher tendency toward the targeted Hg(II) ions compared to the control non-imprinted sorbent particle (NI-PBCS) with a maximum capacity of 315 mg/g. Also, the sorbent displayed relatively rapid adsorption kinetics that best correlated with the pseudo-second-order model.

9.
Bioinorg Chem Appl ; 2022: 3977935, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37388628

RESUMO

The aqueous extract of red algae was used for bio-inspired manufacturing of cobalt oxide nanoparticles (Co3O4NPs) and for antioxidant, antibacterial, hemolytic potency, and anticancer activity. Typical, characterization techniques include UV-Vis, SEM, EDAX, TEM, FTIR, XRD, and TGA. Using an X-ray diffraction assay, the size of the Co3O4NPs crystal was determined to range from 23.2 to 11.8 nm. Based on TEM and SEM pictures, biosynthesized Co3O4NPs' had a homogeneous spherical morphology with a 28.8 to 7.6 nm average diameter. Furthermore, Co3O4NPs biological properties were investigated, including determining the antibacterial potency using the zone of inhibition (ZOI) method and determining the minimal inhibitory concentration (MIC). The antibacterial activity of Co3O4NPs was higher than that of the ciprofloxacin standard. Alternatively, scavenging of DPPH free radical investigation was carried out to test the antioxidant capacitance of Co3O4NPs, revealing significant antioxidant ability. The biosynthesized Co3O4NPs have a dose-dependent effect on erythrocyte viability, indicating that this technique is harmless. Furthermore, bioinspired Co3O4NPs effectively against HepG2 cancer cells (IC50: 201.3 µg/ml). Co3O4NPs would be a therapeutic aid due to their antioxidant, antibacterial, and anticancer properties.

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