Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Sci Rep ; 14(1): 15146, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956108

RESUMO

Nd0.9Zn0.1FeO3 was prepared in a single-phase with an average crystallite size of 25.82 nm using a citrate combustion technique. The energy dispersive X-ray assures the chemical formula of the sample. The elemental mapping of Zn-doped NdFeO3 illustrates the good homogeneous distribution of the elements in the sample. Nd0.9Zn0.1FeO3 has antiferromagnetic properties with weak ferromagnetic components and has good UV absorbance. The values of the band gap for the direct and indirect transitions are 1.473 eV and 1.250 eV, respectively. The adsorption of nickel(II), cobalt(II), chrome(VI), cadmium(II), and lead(II) ions has been studied at pH 7. The highest removal efficiency (η = 73.72%) was observed for the lead ions from water. The current study has examined the kinetics, recoveries, and mechanisms of utilizing Nd0.90Zn0.10FeO3 to remove Pb2+ ions from water. The optimum conditions for the absorbing Pb2+ are pH 7 and a contact time of 60 min. The Freundlich isotherm model is the best model for the absorption of Pb2+ ions. While, the pseudo-second-order kinetic model describes the kinetic adsorption data. The sample has a good efficiency for removing Pb2+ ions from water several times.

2.
Sci Rep ; 13(1): 16585, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37789094

RESUMO

Ho-doped NdFeO3 was synthesized using the citrate method. The X-ray diffraction (XRD) illustrated that Nd0.90Ho0.10FeO3 was crystalline at the nanoscale, with a crystallite size of 39.136 nm. The field emission scanning electron microscope (FESEM) illustrated the porous nature of Nd0.90Ho0.10FeO3, which increases the active sites to absorb the heavy metals on the sample surface. Energy-dispersive X-ray (EDX) data assures the prepared sample has the chemical formula Nd0.90Ho0.10FeO3. The magnetic properties of Nd0.90Ho0.10FeO3 were determined using the magnetization hysteresis loop and Faraday's method. Many magnetic parameters of the sample have been discussed, such as the coercive field, the exchange bias (Hex), and the switching field distribution (SFD). Ho-doped NdFeO3 has an antiferromagnetic (AFM) character with an effective magnetic moment of 3.903 B.M. The UV-visible light absorbance of Nd0.90Ho0.10FeO3 is due to the transfer of electrons from the oxygen 2p state to the iron 3d state. Nd0.90Ho0.10FeO3 nanoparticles have an optical direct transition with an energy gap Eg = 1.106 eV. Ho-doped NdFeO3 can adsorb many heavy metals (Co2+, Ni2+, Pb2+, Cr6+, and Cd2+) from water. The removal efficiency is high for Pb2+ ions, which equals 72.39%. The Langmuir isotherm mode is the best-fit model for adsorbing the Pb2+ ions from water.

3.
Sci Rep ; 13(1): 3141, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823448

RESUMO

Bi-functional nano-oxides are of growing interest to address environmental issues. In the present study, the structural and magnetic data are presented together with the antimicrobial activities (AMA). For the first time, silver delafossite oxide (AgCuO2) is successfully fabricated using a simple, low-cost technique to target antibiotic photodegradation and inactivation of model waterborne pathogens. It is prepared with an equimolar initial Ag+:Cu+ concentration ratio. The structure, morphology, and magnetic properties are studied by different characterization techniques. The size and shape of AgCuO2 NPs, in addition to their structural polytypes of 2H (hexagonal) or 3R (rhombohedral), are dependent on the preparation conditions. The existence of Cu, Ag, and O in the synthesized delafossite AgCuO2 NPs with no evidence of any impurity is ratified by the XPS spectrum. AFM measurements are taken to characterize the surface morphologies of AgCuO2. The distributed spiks are evaluated by roughness kurtosis (Rku). The roughness kurtosis has a value of 2.65 (< 3), indicating that the prepared sample is classified as bumpy. The prepared sample has 13.0, 10.0, 14.0, and 14.0 mm Inhibition Zone Diameter (IZD) antimicrobial activity against gram-positive Bacillus subtilis (B. subtilis), Bacillus cereus (B. cereus), Enterococcus faecalis (E. faecalis), and Staphylococcus aureus (S. aureus), respectively. The IZD for gram-negative Escherichia coli (E. coli), Neisseria Gonorrhoeae (N. Gonorrhoeae), Pseudomonas aeruginosa (P. aeruginosa), and Salmonella typhimrium (S. typhimrium) were found to be 12.0, 13.0, 14.0, and 13.0 mm, respectively. Therefore, the AgCuO2 NPs reveal excellent antimicrobial efficiency, and they can be effortlessly separated using a tiny magnet or a simple magnetic separator. The adequate cytotoxicity and magnetic characteristics of the antimicrobial sample suggest a promising future for it in biomedical applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Escherichia coli , Staphylococcus aureus , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Anti-Infecciosos/química , Antibacterianos/química , Pseudomonas aeruginosa
4.
Lupus ; 15(9): 608-12, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17080918

RESUMO

Plasma and urinary (latent and active) TGF-beta1 levels were assessed in 32 children with active lupus and compared to 15 healthy controls of matched age and sex. Plasma latent and active TGF-beta1 levels in children with active disease were significantly lower than controls (P = 0.004 and P < 0.001 respectively). Plasma active TGF-beta1 correlated negatively with Systemic Lupus Erythematosus Disease Activity Index (r = -0.38, P = 0.03). On the contrary, urinary latent and active TGF-beta1 levels in children with active disease were significantly higher than controls (P < 0.001 and P = 0.003 respectively). Urinary active TGF-beta1 levels correlated positively with Anti-ds DNA titre (r = 0.42, P = 0.015) and negatively with serum C3 levels (r = -0.48, P = 0.005). Patients with symptomatic nephritis had significantly elevated urinary active TGF-beta1 levels in comparison to those with silent nephritis (P = 0.008). From this data we conclude that lowered plasma TGF-beta1 levels may be a feature of systemic immune dysfunction in children with active lupus while increased renal production of active TGF-beta1 seems to have a role in the clinical presentation of lupus nephritis.


Assuntos
Nefrite Lúpica/metabolismo , Fator de Crescimento Transformador beta1/sangue , Fator de Crescimento Transformador beta1/urina , Adolescente , Biomarcadores/sangue , Biomarcadores/urina , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/sangue , Nefrite Lúpica/etiologia , Nefrite Lúpica/urina , Masculino , Proteinúria/etiologia , Proteinúria/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA