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1.
Environ Res ; 247: 118209, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38237757

RESUMEN

The fabrication of all-solid-state Z-scheme sonophotocatalysts is vital for improving the transfer rate of photogenerated electrons to remove antibiotics present in wastewater. Herein, a novel indirect Z-scheme ZnFe-layered double hydroxide (LDH)/reduced graphene oxide (rGO)/graphitic carbon nitride (g-C3N5) heterojunction was synthesized using a simple strategy. The ZnFe-LDH/rGO/g-C3N5 (ZF@rGCN) ternary composites were systematically characterized using different techniques. Results revealed that the 15%ZF@rGCN catalyst achieved a ciprofloxacin (CIP) degradation efficiency of 95% via the synergistic effect of sonocatalysis and photocatalysis. The improved sonophotocatalytic performance of the ZF@rGCN heterojunction was attributed to an increase in the number of active sites, a Z-scheme charge-transfer channel in ZF@rGCN, and an extended visible light response range. The introduction of rGO further enhanced the charge-transfer rate and preserved the reductive and oxidative sites of the ZF@rGCN system, thereby affording additional reactive species to participate in CIP removal. In addition, owing to its unique properties, rGO possibly increased the absorption of incident light and served as an electronic bridge in the as-formed ZF@rGCN catalyst. Finally, the possible CIP degradation pathways and the sonophotocatalytic Z-scheme charge-migration route of ZF@rGCN were proposed. This study presents a new approach for fabricating highly efficient Z-scheme sonophotocatalysts for environmental remediation.


Asunto(s)
Ciprofloxacina , Restauración y Remediación Ambiental , Grafito , Antibacterianos , Electrones
2.
J Fish Dis ; 38(4): 389-403, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24720625

RESUMEN

We investigated mass mortalities of koi, Cyprinus carpio Linnaeus, 1758, experienced in South Indian fish farms by virus isolation, electron microscopy, PCR detection, sequencing of capsid protein gene and transmission studies. Samples of moribund koi brought to the laboratory suffered continuous mortality exhibiting swimming abnormalities, intermittent surfacing and skin darkening. Irido-like virus was isolated from the infected fish in the indigenous snakehead kidney cell line (SNKD2a). Icosahedral virus particles of 100 to 120 nm were observed in the infected cell cultures, budding from the cell membrane. Virus transmission and pathogenicity studies revealed that horizontal transmission occurred associated with mortality. PCR analysis of infected fish and cell cultures confirmed the presence of Ranavirus capsid protein sequences. Sequence analysis of the major capsid protein gene showed an identity of 99.9% to that of largemouth bass virus isolated from North America. Detection and successful isolation of this viral agent becomes the first record of isolation of a virus resembling Santee-Cooper Ranavirus from a koi and from India. We propose the name koi ranavirus to this agent.


Asunto(s)
Infecciones por Virus ADN/veterinaria , Enfermedades de los Peces/virología , Animales , Proteínas de la Cápside/genética , Carpas , Línea Celular , Infecciones por Virus ADN/diagnóstico , Infecciones por Virus ADN/patología , Infecciones por Virus ADN/transmisión , Infecciones por Virus ADN/virología , Enfermedades de los Peces/diagnóstico , Enfermedades de los Peces/genética , Enfermedades de los Peces/patología , Enfermedades de los Peces/transmisión , Explotaciones Pesqueras , India , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Ranavirus/genética , Ranavirus/aislamiento & purificación , Ranavirus/ultraestructura
3.
J Phys Chem B ; 124(3): 443-450, 2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31609633

RESUMEN

The mathematical model of Oldham J. Phys. Chem. B 2000 , 104 , 4703 for rotating disc electrode in an unsupported system is discussed. This article presents a new analytical method for the calculation of concentration at a rotating disc electrode controlled by diffusion, convection, and migration. This model contains a steady-state nonlinear differential equation in a three-ion system under the assumption that all the ions have the same diffusivity. The homotopy perturbation method is employed to solve the nonlinear governing equation, where the ionic concentration and current are obtained analytically, in terms of charge numbers. The comparison between the analytical results of this study and previous studies confirms that the result of the proposed method is in stronger agreement with numerical simulations than other analytical methods.

4.
Saudi J Biol Sci ; 27(12): 3753-3758, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33304187

RESUMEN

In the present study, sulphated polysaccharide Ulvan from Ulva lactuca was used for the synthesis of biogenic Selenium Nanoparticles (SeNPs) conjugate and Mouth rinse was prepared using this conjugate. The synthesis of nanoparticles was confirmed by UV-Visible spectrophotometry and characterized using Fourier transform infrared spectroscopy (FTIR), transmission electron microscope (TEM) and X-ray diffraction (XRD). TEM showed that the average size of the nanoparticle was 85 nm and spherical in shape. Furthermore, nanoparticle conjugates were evaluated for cell viability using MTT assay 3T3-L1 cell line and at 30 µl/ml showed 34% cell viability. The antimicrobial activity of SeNPs mouth rinse was tested against oral pathogens such as Streptococcus mutans, Staphylococcus aureus, Lactobacillus, and Candida albicans and it was effective against all tested microorganism at the concentration of 100 µl/ml. The present study has shown that Ulvan from algal biomass can be a safe and effective source for the development of oral nano-antimicrobial agents.

5.
ISA Trans ; 77: 30-48, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29729976

RESUMEN

This study examines the problem of robust reliable control for Takagi-Sugeno (T-S) fuzzy Markovian jumping delayed neural networks with probabilistic actuator faults and leakage terms. An event-triggered communication scheme. First, the randomly occurring actuator faults and their failures rates are governed by two sets of unrelated random variables satisfying certain probabilistic failures of every actuator, new type of distribution based event triggered fault model is proposed, which utilize the effect of transmission delay. Second, Takagi-Sugeno (T-S) fuzzy model is adopted for the neural networks and the randomness of actuators failures is modeled in a Markov jump model framework. Third, to guarantee the considered closed-loop system is exponential mean square stable with a prescribed reliable control performance, a Markov jump event-triggered scheme is designed in this paper, which is the main purpose of our study. Fourth, by constructing appropriate Lyapunov-Krasovskii functional, employing Newton-Leibniz formulation and integral inequalities, several delay-dependent criteria for the solvability of the addressed problem are derived. The obtained stability criteria are stated in terms of linear matrix inequalities (LMIs), which can be checked numerically using the effective LMI toolbox in MATLAB. Finally, numerical examples are given to illustrate the effectiveness and reduced conservatism of the proposed results over the existing ones, among them one example was supported by real-life application of the benchmark problem.

6.
Contemp Clin Dent ; 9(2): 200-204, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29875561

RESUMEN

AIM: The purpose of this study is to evaluate the increase in the width of attached gingiva (AG) in single/multiple adjacent teeth using variation of modified apically repositioned flap (MARF). MATERIALS AND METHODS: A total of 20 systemically healthy controls with inadequate width of AG were recruited for the study based on inclusion and exclusion criteria. In all the individuals, variation of MARF technique was performed to increase the width of AG. Outcomes of the surgical techniques were measured in terms of probing pocket depth, clinical attachment level, width of AG, and width of keratinized gingiva (KG). The results were followed up at 3 months and continued till 9 months to confirm the stability of results. RESULTS: Treatment with this procedure resulted in a significant increase in the width of the KG and AG. The increase in KG ranged from baseline (2.0 mm) to 3.85 mm at 3rd month and the results were stable till 9th month (P < 0.001), and the increase in AG ranged from baseline (1.0 mm) to 2.85 mm at 3rd month and the results were stable till 9th month (P < 0.001). CONCLUSION: MARF is an effective technique in increasing the width of the keratinized tissue and AG around teeth and also offers considerable advantages over other mucogingival surgery techniques.

7.
Waste Manag ; 77: 565-575, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29778404

RESUMEN

Aluminium dross, a waste generated from aluminium melting process, contains aluminium metal, aluminium oxide, aluminium oxy-nitride and impurities such as sodium chloride and potassium chloride. Since aluminium dross is land filled without treatment, it is hazardous to the environment. Conventional methods for the metal recovery from the recycling of aluminium dross involve chemicals and are time consuming. In this study, an attempt was made to treat aluminium dross using plasma arc melting process. The aluminium dross was melted and evaporated by the plasma arc established between a crucible anode and a rod type hollow cathode made of graphite. Raw dross and products of plasma treated dross such as slag and fine powder were characterized. The generation of ultrafine alumina powder and slag are explained using simulation of the plasma arc inside the crucible and free energy minimization calculations. High temperature and air entrainment into the plasma inside the crucible converted the dross into alumina slag and fine powder. The amount of fine alumina powder produced increased substantially with plasma power initially as seen from the results of alumina obtained at 5 kW and 10 kW. However, further increase in plasma power resulted only in marginal increase in the conversion of Al dross to alumina. Results of this study indicate that arc plasma technology can be effectively applied to convert Al dross into value added fine alumina powder.


Asunto(s)
Aluminio , Reciclaje , Óxido de Aluminio , Administración de Residuos
8.
Neural Netw ; 86: 10-17, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27923168

RESUMEN

This article examines the exponential stability analysis problem of generalized neural networks (GNNs) including interval time-varying delayed states. A new improved exponential stability criterion is presented by establishing a proper Lyapunov-Krasovskii functional (LKF) and employing new analysis theory. The improved reciprocally convex combination (RCC) and weighted integral inequality (WII) techniques are utilized to obtain new sufficient conditions to ascertain the exponential stability result of such delayed GNNs. The superiority of the obtained results is clearly demonstrated by numerical examples.


Asunto(s)
Simulación por Computador , Redes Neurales de la Computación , Simulación por Computador/tendencias , Humanos , Percepción del Tiempo
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