In this study Ziziphus nummularia (ZPN) as a good, available and inexpensive adsorbent has been introduced and used for the removal of Bromocresol Green (BCG) from several water solutions successfully. The effect of various parameters such as pH, dye concentration, amount of adsorbent, size of adsorbent particles, and contact time on removal processing was investigated.To investigate the mechanism of adsorption, several kinetic models were tested including Lagergren, pseudosecond-order, particle diffusion, film diffusion, and Elovich models. Adsorption isothermal data could be interpreted by the Langmuir, Freundlich, Tempkin, and DubininÀRudushkevich (DR) isotherm models. Thermodynamic parameters like free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) of the system were calculated.' EXPERIMENTAL SECTION Materials. BCG with the molecular formula C 12 H 14 Br 4 O
Purpose: Nanoporous membranes have been employing more than before in applications such as biomedical due to nanometer hexagonal pores array. Biofouling is one of the important problems in these applications that used nanoporous membranes and are in close contact with microorganisms. Surface modification of the membrane is one way to prevent biofilm formation; therefore, the membrane made in this work is modified with carbon nanotubes. Methods: In this work, nanoporous solid-state membrane (NSSM) was made by a two-step anodization method, and then modified with carbon nanotubes (NSSM-multi-wall carbon nanotubes [MWCNT]) by a simple chemical reaction. Techniques such as atomic force microscopy (AFM), energy dispersive X-ray (EDAX), field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), contact angle (CA), surface free energy (SFE), protein adsorption, flow cytometry, and MTT assay were used for membrane characterization. Results: The BSA protein adsorption capacity reduced from 992.54 to 97.24 (μg mL-1 cm-2) after modification. The findings of flow cytometry and MTT assay confirmed that the number of dead bacteria was higher on the NSSM-MWCNT surface than that of control. Adsorption models of Freundlich and Langmuir and kinetics models were studied to understand the governing mechanism by which bacteria migrate to the membrane surface. Conclusion: The cell viability of absorbed bacteria on the NSSM-MWCNT was disrupted in direct physical contact with carbon nanotubes. Then, the dead bacteria were desorbed from the surface of the hydrophilic membrane. The results of this research showed that NSSM-MWCNT containing carbon nanotubes have significant antimicrobial and self-cleaning property that can be used in many biomedical devices without facing the eminent problem of biofouling.
In the present study, a new method for monitoring the signal after cloud point extraction (CPE) of dyes is introduced. The CPE-Paptode method was used to determine acid red 151, as an anionic dye. The method is based on the CPE of dye from aqueous solution, using Triton X-114, diluting the extracted surfactant-rich phase with ethanol and measuring the RGB parameters by special software written in visual basic (VB 6). Parameters, such as pH of the system, the concentration of the dye and surfactant, equilibration temperature and time, as effective parameters on the extraction efficiency and the determination of the dye, were investigated and optimized. Under the optimal conditions, the calibration curve was linear in the range of 0.5-19.0 mg L À1 . Preconcentration of a 15 mL sample gave an enhancement factor of 13.2 and a detection limit of 0.32 mg L À1 . In addition, the effects of some foreign species including cations, anions and dyes were investigated. The method was successfully applied to the determination of the acid red 151 content in aqueous solution. The results and the figure of merits of the proposed method were comparable with those of CPE-spectrophotometry.
Purpose: Alumina substrates are one of the commonly used scaffolds applied in cell culture, but in order to prevent formation of biofilm on the alumina substrate, these substrates are modified with carbon nanotube. Methods: The alumina substrate was made by a two-step anodization method and was then modified with carbon nanotubes by simple chemical reaction. The substrates were characterized with FTIR, SEM, EDX, 3D laser scanning digital microscope, contact angle (CA) and surface free energy (SFE). To determine how this modification influences the reduction of biofilm, biofilm of two various bacteria, Escherichia coli (E.coli) and Staphylococcus aureus (S. aureus), were investigated. Results: The biofilm on the modified substrate decreased due to the presence of carbon nanotubes and increased antibacterial properties. Dental pulp stem cells (DPSCs) were cultured onto flat alumina (FA) and nanoporous alumina-multiwalled carbon nanotubes (NAMC) substrates to examine how the chemical modification and surface topography affects growth of DPSCs. Conclusion: Cell attachment and proliferation were investigated with SEM and Presto Blue assay, and the findings show that the NAMC substrates are suitable for cell culture.
In this paper by using the coherent state path integral field theory approach, we calculate the grand canonical partition function of an interacting combined system in the presence of the relevant source terms. It allows us to calculate multi-time correlation functions of interacting systems without using the quantum regression theorem. Then, we investigate the power spectrum and the second-order correlation function of the emitted photons from a microcavity in the presence of excitations of a semiconductor quantum well. By using the Hubbard-Stratonovich transformation, we investigate the effects of reservoir, detuning, the Coulomb interaction and the phase space filling on the power spectrum and the second-order correlation function of the emitted photons.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.