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1.
Sci Rep ; 14(1): 14452, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914569

RESUMO

The development of flame-retardant materials has become an important research direction. For the past dozen years, researchers have been exploring flame retardants with high flame-retardant efficiency, low toxicity, less smoke, or other excellent performance flame retardants. Therefore, this work aimed to synthesize new cyclodiphosph(V)azane derivatives and their Cu(II) and Cd(II) metal complexes and investigated their potential applications as high flame-retardant efficiency. Various techniques were used to characterize the prepared ligand H2L and its metal complexes, including elemental analyses, mass spectra, conductivity measurements, electronic spectral data UV-vis, FT-IR, 1H,13C-NMR, TGA, XRD, and molecular docking experiments studies were M. tuberculosis receptors (PDB ID: 5UHF) and the crystal structure of human topoisomerase II alpha (PDB ID: 4FM9). Wood-based paint was physically mixed with the ligand H2L and its metal complexes. The obtained results of mechanical characteristics of the dried paint layers were noticed to improve, such as gloss value, which ranged from 85 to 95, hardness 1.5-2.5 kg, adhesion 4B to 5B, and impact resistance, which improved from 1.3 to 2.5 J. Moreover, the obtained results of flame-retardant properties showed a significant retardant impact compared to the blank sample, such as ignitability, which includes the heat flux which increased from 10 to 25 kW/m2, and ignition time, ranging from 550 to 1200 s, respectively, and limiting oxygen index (LOI) (%) which has been increased from 21 to 130 compared with the plywood sample and sample blank. The ordering activity of the observed results was noticed that coated sample based on Cd(II) metal complexes > coated sample based on Cu(II) metal complexes of Cyclophosphazene ligand > coated sample based on phosphazene ligand H2L > coated sample without additives > uncoated sample. This efficiency may be attributed to (1) the H2L is an organophosphorus compound, which contains P, N, Cl, and aromatic six- and five-member ring, (2) Cu(II) and Cd(II) metal complexes characterized by high thermal stability, good stability, excellent performance flame retardants, and wide application.

2.
RSC Adv ; 14(23): 15942-15952, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38756847

RESUMO

Numerous pollutants endanger the safety and purity of water, making water pollution a major worldwide concern. The health of people and aquatic ecosystems are at risk from these contaminants, which include hazardous microbes, industrial waste, and agricultural runoff. Fortunately, there appears to be a viable option to address this problem with adsorptive water treatment techniques. The present study presents a magnetic adsorbent (MMIP) based on molecularly imprinted polyaniline and magnetite nanoparticles for the solid-phase extraction of diclofenac, an anti-inflammatory medication, from industrial wastewater. The adsorbent nanomaterial was characterized using dynamic light scattering, zeta potential measurement, vibrating sample magnetometry, X-ray diffraction, and scanning electron microscopy. The MMIP demonstrated a particle size of 86.3 nm and an adsorption capacity of 139.7 mg g-1 at 600 mg L-1 of diclofenac and after a 200 min incubation period. The highest %removal was attained at pH range of 3-7. The adsorption process follows the pseudo-second order kinetic model. In addition, it was found that the adsorption process is enthalpy-driven and may occur via hydrogen bonding and/or van der Waals interactions.

3.
Front Chem ; 12: 1357330, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38410818

RESUMO

The main objective of this study is to synthesize and characterize of a new three complexes of Pd (II), Cu (II), and Cu (I) metal ions with novel ligand ((Z)-2-(phenylamino)-N'-(thiophen-2-ylmethylene)acetohydrazide) H2LB. The structural composition of new compounds was assessed using several analytical techniques including FT-IR, 1H-NMR, electronic spectra, powder X-ray diffraction, and thermal behavior analysis. The Gaussian09 program employed the Density Functional Theory (DFT) approach to optimize the geometry of all synthesized compounds, therefore obtaining the most favorable structures and crucial parameters. An investigation was conducted to examine the impact of γ-irradiation on ligands and complexes. Before and after γ-irradiation, the antimicrobial efficiency was investigated for the activity of ligands and their chelates. The Cu(I) complex demonstrated enhanced antibacterial activity after irradiation, as well as other standard medications such as ampicillin and gentamicin. Similarly, the Cu(I) complex exhibited superior activity against antifungal species relative to the standard drug Nystatin. The docking investigation utilized the target location of the topoisomerase enzyme (2xct) chain A.

4.
Sci Rep ; 13(1): 14991, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696841

RESUMO

The great demand on the energy makes the attention toward modifying lubricating oil. This work tends to prepare the following copolymers; octadecylmethacrylate-co-dodecene (CP1) and octadecylmethacrylate-co-hexadecene (CP2) by free radical solution polymerization using laboratory prepared octadecylmethacrylate monomer with either 1-dodecene or 1-hexadecene. The same monomers also used to prepare their polymers nanocomposite (NP1, NP2) with 1% of nanomontmorolonite by emulsion polymerization. The structures of the prepared polymers and their nanocomposite were elucidated by FTIR, 1HNMR, TGA, DSC, TEM and DLS. These polymers were used as pour point depressant, flow improver and viscosity modifier and showed high efficiency. After comparison of the data of the polymers and their nanocomposite, the nanocomposite give the best results where the pour point decreased from 0 °C to - 18, - 27, - 24 and - 33 °C for CP1, CP2, NP1 and NP2 respectively at the optimum concentration 10,000 ppm. On the other hand the viscosity index increased from 86.57 to 93.25, 92.41, 94.17 and 93.103 for CP1, CP2, NP1 and NP2 respectively, the apparent viscosity increased from 55.863 to 69.31, 119.41, 111.28, and 166.89 cP also the yield stress increased from 652.19 to 1076.3, 1074 and 1480 D/cm2 for CP1, CP2, NP1 and NP2 respectively.

5.
Int Orthod ; 21(1): 100711, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36463787

RESUMO

BACKGROUND: Overcoming the failure percentage of orthodontic mini-screws (OMSs), which is about 30% of overall orthodontic cases, especially in malocclusion treatment that requires orthopaedic heavy forces, is a great challenge. Bacterial infections, soft tissue and bone inflammation, and weak connections between bones and the OMS surface are among the main causalities of this failure. OBJECTIVE: The aim of the study is to evaluate in vitro the microbiological activities of the deposited nanomaterials (Silver/hydroxyapatite nanoparticles (Ag/HA NPs) and zinc oxide nanoparticles (ZnO NPs)) in terms of microbial inhibition. In addition, the in-vitro cytotoxicity and cytocompatibility of the synthesized nano-coatings prior to their in-vivo application in animal models were tested on four types of cells, namely, fibroblasts, osteocytes, osteoblasts, and oral epithelial cells. MATERIALS AND METHODS: Ag/HA NPs and ZnO NPs were built up onto the surface of titanium OMSs by electrochemical deposition. This electrochemical deposition was performed on 50 orthodontic mini screws and the deposited materials were characterized with the aid of scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX) analysis, X-ray Diffraction (XRD) and nano-scratch test. In addition, the microbiological activities of the deposited nanomaterials were explored in vitro in terms of microbial inhibition. Furthermore, the cytotoxicity and cytocompatibility were tested on four types of cells, namely, fibroblasts, osteocytes, osteoblasts and oral epithelial cells. RESULTS: SEM images revealed spherical Ag NPs in the range of 40-70nm in diameter, rod-shaped HA NPs and porous scaly ZnO NPs on the surface of the OMSs. XRD analysis confirmed the crystal structures of AgNPs, HA NPs, and ZnO NPs. ZnO NPs coated OMS had the highest antimicrobial activity than Ag/HA coated OMS against Gram-positive, Gram-negative and fungal strains. Moreover, after incubation, the decrease in the number of bacterial colonies was significant with ZnO and Ag/HA nanoparticles (with the greatest decrease for the former), due to the potent antibacterial effect of nanoparticles against Escherichia coli and Enterococcus faecalis. Moreover, ZnO NPs-coated OMSs showed a better cytocompatibility with oral epithelium, bone cells, and fibroblasts compared to Ag/HA NPs. CONCLUSION: The suggested nanocoating is a promising strategy to overcome the development of an inflammatory zone around the fixed OMSs.


Assuntos
Óxido de Zinco , Animais , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Prata/farmacologia , Prata/química , Titânio , Durapatita/farmacologia , Inflamação
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