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1.
Sci Total Environ ; 923: 171277, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38408651

RESUMO

Black sand along the Red Sea is often composed of volcanic minerals and heavy minerals. The Red Sea region is known for its unique geological features, and black sand beaches can be found in various areas along its shores. The study presents a comprehensive semi-quantitative chemical analysis of black sand samples collected from various locations along the red sea, revealing significant variations in their elemental compositions. The main oxides were identified in each sample, determined through X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses, indicate diverse mineralogical compositions. The spatial distribution of minerals at each site is depicted through mapping. Additionally, Fourier-transform infrared (FTIR) spectra offer information on the functional groups present in the samples, revealing the existence of hydroxyl groups, aliphatic compounds, and adsorbed water molecules. For Qusier-Elsharm Alqbly, Safaga, Marsa Alam, Gabal Alrosass, Hurghada Titanic, Hurghada Elahiaa, Gemsa, and Ras Elbehar samples, the results highlight the presence of various minerals, such as Quartz, Calcite, Titanium Dioxide, Magnetite, Hematite, Aluminum Oxide, Zirconium Dioxide, Chromium (III) Oxide, and others, providing insights into the geological characteristics of each location. The differences in mineral content among the examined sites are linked to the geological and mineralogical makeup of the source rocks upstream and midstream in the basins that discharge into the surveyed regions. So, variations in black sand concentrations among different locations offer insights into the geological and mineralogical diversity of the studied areas along the Red Sea coast. This study addresses the existing knowledge gap by focusing on the preliminary exploration and description of the occurrence, distribution, and composition of black sand along the Red Sea in Egypt. whereas the results provide valuable insights into the geological diversity of black sand deposits in the surveyed areas, underscoring the need for additional research and interpretation of these variations. Therefore, the in-depth examination of mineralogical composition and crystal structures establishes a foundation for future investigations in the field of geology and earth sciences.

2.
Biochim Biophys Acta Gen Subj ; 1868(3): 130543, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38103758

RESUMO

Novel biocompatible and effective hyperthermia (HT) treatment materials for breast cancer therapeutic have recently attracting researchers, because of their effective ablation of cancer cells and negligible damage to healthy cells. Magnetoliposome (MLs) have numerous possibilities for utilize in cancer treatment, including smart drug delivery (SDD) mediated through alternating magnetic fields (AMF). In this work, magnesium ferrite (MgFe2O4) encapsulated with liposomes lipid bilayer (MLs), Quercetin (Q)-loaded MgFe2O4@Liposomes (Q-MLs) nano-hybrid system were successfully synthesized for magnetic hyperthermia (MHT) and SDD applications. The hybrid system was well-investigated by different techniques using X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FT-IR), Energy dispersive X-ray (EDX), Vibrating sample magnetometer (VSM), Transmission electron microscope (TEM), and Zeta Potential (ZP). The characterization results confirmed the improving quercetin-loading on the MLs surface. TEM analysis indicated the synthesized MgFe2O4, MLs, and Q-MLs were spherical with an average size of 23.7, 35.5, and 329.5 nm, respectively. The VSM results revealed that the MgFe2O4 exhibit excellent and effective saturation magnetization (MS) (40.5 emu/g). Quercetin drug loading and entrapment efficiency were found to be equal to 2.1 ± 0.1% and 42.3 ± 2.2%, respectively. The in-vitro Q release from Q-loaded MLs was found 40.2% at pH 5.1 and 69.87% at pH 7.4, verifying the Q-loading pH sensitivity. The MLs and Q-MLs hybrid system as MHT agents exhibit specific absorption rate (SAR) values of 197 and 205 W/g, correspondingly. Furthermore, the Q-MLs cytotoxicity was studied on the MCF-7 breast cancer cell line, and the obtained data demonstrated that the Q-MLs have a high cytotoxicity effect compared to MLs and free Q.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Humanos , Feminino , Lipossomos/química , Quercetina/farmacologia , Quercetina/química , Neoplasias da Mama/tratamento farmacológico , Bicamadas Lipídicas , Células MCF-7 , Espectroscopia de Infravermelho com Transformada de Fourier , Hipertermia Induzida/métodos , Fenômenos Magnéticos
3.
Int J Biol Macromol ; 258(Pt 1): 128890, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38134996

RESUMO

The release of harmful organic dyes from different industries besides its degradation products is a major contributor to environmental contamination. The catalytic reduction of these organic pollutants using nanocomposites based on polymeric material presents potential advantages for the environment. In this study, novel nanocomposite based on cellulose acetate (CA)-derived from discharged cigarette butts and zinc oxide nanoparticles (ZnO NPs) was prepared utilizing a very simple and low-cost solution blending method and used as support for silver nanoparticles (Ag NPs). A simple reduction method was used to anchor different percentages of Ag NPs on the ZnO@CA nanocomposite surface via utilizing sodium borohydride as a reducing agent. The Ag-ZnO@CA nanocomposite was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The TEM analysis showed spherical Ag NPs, with an average diameter of ∼17.6 nm, were uniformly anchored on the ZnO@CA nanocomposite surface. The prepared nanocomposites were evaluated as catalysts for the reduction of organic dyes in water. It was found that 10 % Ag-ZnO@CA nanocomposite showed a remarkable reduction of Rhodamine B (RhB), Rhodamine 6G (Rh6G), Methylene Blue (MB), and Sunset Yellow (SY) dyes in short time. In the presence of this nanocomposite, the rate constant, kapp values for RhB, Rh6G, MB, and SY were 0.3498 min-1, 1.51 min-1, 0.2292 min-1, and 0.733 min-1, respectively. This nanocomposite was recovered and reused in five successive cycles, with a negligible loss of its activity. Furthermore, the nanocomposites demonstrated moderate antibacterial activity toward Staphylococcus aureus and Escherichia coli. Thus, this study directed attention on recycling of waste material to a valuable nanocomposite and its applications in environmental protection.


Assuntos
Celulose/análogos & derivados , Nanopartículas Metálicas , Nanocompostos , Óxido de Zinco , Óxido de Zinco/química , Prata/química , Nanopartículas Metálicas/química , Antibacterianos/química , Escherichia coli , Nanocompostos/química , Corantes
4.
ACS Omega ; 7(30): 26777-26787, 2022 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35936455

RESUMO

Metallic copper nanoparticle (Cu NP)-doped 1D hydroxyapatite was synthesized using a simple chemical reduction method. To describe the structure and composition of the Cu/HAP nanocomposites, physicochemical techniques such as X-ray diffraction, Fourier transform infrared spectroscopy, inductively coupled plasma, N2 adsorption-desorption, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy were used. The TEM scan of the Cu/HAP nanocomposite revealed a rod-like shape with 308 nm length and 117 nm width on average. The catalytic activity of Cu/HAP nanocomposites for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the presence of NaBH4 has been thoroughly investigated. The 0.7% Cu/HAP nanocomposite was shown to have superior catalytic activity than the other nanocomposites, converting 4-NP to 4-AP in ∼1 min with good recyclability. Moreover, this nanocomposite showed excellent catalytic performance in the organic dye reduction such as Congo red and acriflavine hydrochloride dyes. The high dispersion of Cu NPs on HAP support, the high specific surface area, and the small Cu particles contributed to its remarkable catalytic performance.

5.
Sci Rep ; 12(1): 9407, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672397

RESUMO

In this work, the production of dimethyl ether (DME) from methanol over natural kaolin clay modified through impregnation with various percentages of H2SO4, WO3, or ZrO2 catalysts was investigated. The prepared catalysts were characterized via X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and N2-sorption analysis. The acidity of these catalysts was determined through the dehydration of isopropyl alcohol and the chemisorption of pyridine. The catalytic activity performance revealed that the addition of modifiers into kaolin enhanced the latter's activity toward DME production. In addition, the kaolin clay modified with 10 wt% ZrO2 exhibited excellent activity of 98% conversion with 100% selectivity at 275 °C. Moreover, this catalyst could proceed the reaction for a long time (6 days) without any noticeable deactivation. The remarkable improvement in the catalytic performance achievement was well correlated with the acidity and the structure of the catalysts.

6.
RSC Adv ; 12(26): 16496-16509, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35754865

RESUMO

In this work, Cu NPs were loaded at a fixed percentage (5 wt%) on 1D, (1D + 0D) and 0D ZnO nanostructures to investigate the effect of the support morphology on the reduction of organic pollutants in water. The synthesized materials were characterized by high-resolution transmission electron microscopy (HR-TEM), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), N2 adsorption-desorption and X-ray photoelectron spectroscopy (XPS). The results reveal that the loading of Cu NPs decreases the optical band gap, and a slight change in the crystallite sizes increases the specific surface area value of the nanocomposites. The TEM images reveal that 1D ZnO has an average width of 44.7 nm and an average length of 211 nm, while 0D ZnO has an average diameter of 54.5 nm. The HR-TEM and XPS data confirm the loading of metallic Cu NPs on the surface of the ZnO nanostructures. The pure ZnO and nanocomposites were tested for 4-nitrophenol (4-NP) reduction in the presence of NaBH4 at room temperature. The obtained results show that pure ZnO nanostructures have no catalytic performance, while the nanocomposites showed good catalytic activities. The catalytic reduction efficiency of 4-NP was found to follow the order of Cu/0DZnO > Cu/(1D + 0D)ZnO > Cu/1DZnO. The complete reduction of 4-NP has been observed to be achievable within 60 s using the Cu/0DZnO nanocomposite, with a k app value of 8.42 min-1 and good recyclability of up to five cycles. This nanocomposite was then applied in the reduction of organic dyes in water; it was found that the reduction rate constants for the methylene blue, Congo red, and acriflavine hydrochloride dyes were 1.4 min-1, 1.2 min-1, and 3.81 min-1, respectively. The high catalytic performance of this nanocomposite may be due to the small particle size, high specific surface area, and the high dispersion of Cu NPs on the surface of ZnO.

7.
ACS Omega ; 7(18): 16109-16115, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35571771

RESUMO

The oxidation of 3',3″-dibromothymolsulfonphthalein (DBTS) in neutral medium by potassium permanganate multi-equivalent oxidant has been studied spectrophotometrically. Pseudo-first-order plots showed inverted S-shape throughout the entire course of the reaction. The initial rates were found to be relatively fast in the early stages, followed by a decrease in the oxidation rates over longer time periods in the slow stage. Under pseudo-first-order conditions where [DBTS] ≫ 10 [MnO4 -], the experimental results showed a first-order dependence in [MnO4 -] and fractional-first-order kinetics in the [DBTS] concentration. The formation of 1:1 coordination intermediate complex prior to the rate-determining step was revealed kinetically. In addition, the intermediate species involving complexes of Mn(V) coordination has been detected. The oxidation product of DBTS was identified by Fourier transform infrared spectroscopy, ultraviolet-visible spectrophotometry, and gas chromatography-mass analysis. The obtained results indicated the formation of 2-bromo-6-isopropyl-3-methyl-cyclohexa-2,5-dienone as a derivative oxidation of DBTS.

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