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In this study, a nanocarrier was prepared for targeted delivery of doxorubicin (DOX), as a drug model, to cancer cells. To this end, nontoxic Fe3O4 nanoparticles (NPs) were first synthesized by the co-precipitation method. The NPs then underwent surface functionalization by hydrophilic and biocompatible polyethylene glycol (PEG) to improve their stability. The Fe3O4@PEG was eventually decorated by graphene quantum dots (GQDs) for imparting specific optical properties and increase its drug loading capacity. The obtained nanocarriers (Fe3O4@PEG@GQD) exhibited low toxicity, hydrodynamic diameter of 129 nm, and a drug loading content of 27%, along with superior superparamagnetic properties. Also, the morphology of nanocarrier was surveyed by
It has been reported that the dispersing ability of a given surfactant in surfactant-assisted liquid-phase exfoliation of graphite is extremely affected by its adsorption energy on graphene nanosheets. This study employs computational and experimental techniques to analyze the true relationship between adsorption energy and the dispersing ability of a group of surfactants in the surfactant-assisted liquid-phase exfoliation of graphite. In the first section, adsorption energies computed for a group of homologous surfactants with different hydrocarbon tail lengths are used to predict dispersing-ability trends. It is found that the adsorption energy of the surfactants correlates directly with their tail length. In light of the literature, it i
The corrosion rate of coated zinc in a 3.5 wt. % NaCl electrolyte solution was studied. Epoxy resin coatings loaded with polypyrrole/dodecyl benzene sulfonate/quaternized alkyl pyridine and polypyrrole/dodecyl benzene sulfonate nanocapsules were compared to a non-loaded resin coating. Nanocapsule-loaded coatings exhibited improved self-healing corrosion inhibitory properties. Nanocapsules were characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). Atomic force microscopy (AFM), FESEM and EDX maps analysis confirmed the uniform dispersion of polymer nanocapsules in epoxy resin coatings. Self-healing properties were
The current work investigates the effect of ethylene glycol (EG) on the surface and aggregation behavior of two ester-containing gemini surfactants (i.e., esterquat and betainate). EG, as a cosolvent, was added to aqueous surfactant solutions in three different percentages including 20, 35, and 50 (v/v %). The formation of surfactant aggregates was investigated using dynamic light scattering, zeta potential, and transmission electron microscopy. Several physical–chemical properties such as critical micelle concentration (cmc), Gibbs free energy of micellization (ΔGmic?), interfacial properties, degree of counterion dissociation (α), and morphology of aggregates were also determined in the absence and presence of EG. By increasing the co
The phase transition behavior and structure of an ionic liquid crystal (ILC), 1,3 detetradecyl imidazolium bromide [C14H29Im C14H29] Br–, with double alkyl chain lengths and binary mixtures of 4-cyano-4′-pentylbiphenyl (5CB) with [C14Im C14] Br– were studied by wide-angle X-ray scattering, differential scanning calorimetry, and polarizing optical microscopy. These ILCs can form a high-ordered mesophase smectic-A beside the plastic crystalline phases and also the isotropic state because of the formation of a three-dimensional network by noncovalent bonding. The phase behaviors of binary mixtures show a different phase transition compared to each pure compound. Also, the smectic (Sm-A) to I phase transition temperatures in binary mixtur
Single-layer phosphorene is a unique material with distinctive properties resulting in its high potential to be used as an anode in alkali metal ion batteries (AIBs). In this study, the improvement of the adsorption energy, the diffusion, and the storage capacity of alkali metals (Li, Na, and K) in a pristine and defective monolayer phosphorene was systematically studied using first-principles calculations. All possible defects on phosphorene were studied by electronic structure analysis. The pristine phosphorene strongly adsorbed Li, Na, and K with adsorption energies of −2.08 eV, −1.33 eV, and −2.16 eV, respectively. Interestingly, the presence of point defects significantly enhanced the binding of the alkali metals with adsorption
With development of industrial activities, a lot of oil pollution is released to water environment. As such, superhydrophobic oil adsorption materials with reusability are required. For this purpose, a magnetic superhydrophobic polyurethane sponge by connecting graphene oxide was coated with functionalized oleic acid Fe3O4 nanoparticles on the three-dimensional microstructure of commercial polyurethane sponge (Fe3O4@OA@GO-PU) via simple and low-cost dip coating method. Characterization analysis were used to confirm the synthesis of modified sponge. The eco-friendly effective modified sponge repelled water with contact angle 158? and selectively adsorbed organic solvents and various oils from water with high adsorption capacity. The water co
In this study, evolution of single wall carbon nanotube (SWCNT) structure in E7CN7 nematic liquid crystals (NLCs) and also the electrophysical characteristics of a mixture of the NLCs doped with SWCNT were investigated in the concentration range between 0.25 and 1 wt%. The measurements were carried out in sandwich cells with transparent electrodes, and electric field applied out-of-plane, i.e., perpendicularly to the cells. The results of the carbon nanotube structure changing caused by increasing concentration, can be considered into two regions: (1) branch aggregations in concentrations below 0.5 wt%, (2) percolation network in the concentration range between 0.5 and 1 wt%. In the first region, conductivity decreases while in the se
A new phenomenon, i.e. the improvement of the adsorption energy and the diffusion of Li ion in a phosphorene monolayer under the effect of perpendicular external electric field (EEF) was studied using M06-2X/6-31G(d,p) density functional theory (DFT) framework, and also outcomes were compared with the results obtained by using of graphene. Potential energy surface (PES) scanning and analysis of origin-dependency of charged molecular systems’ energy, were used to obtain intrinsic binding energy of the charged molecular compounds within the external electric field. Our calculations revealed that, increasing the strength of field from −0.02 to 0.032 a u, caused the adsorption energies of the Li ion in the phosphorene monolayer to be incr
The E7 Nematic liquid crystal (NLC) doped with Graphene quantum dots (GQDs) have been obtanied by bottom-up approaches to improve thermodynamics and electrochemical properties. The NI phase transition temperature and enthalpy were increased in comparison with the pure E7. The anchoring effect plays a key role in NI phase transition Also, the Ea values was decreased in doped GQDs system comapre to pure E7. The electrical conductivity of the doped GQD system was significantly more than pure E7. GQDs doping does significantly affect the permittivity of the nematic host, it noticeably increases its charge capacitance.
Oily wastewater treatment has been proved to be one of the most crucial environmental concerns. In the present study, in the first step, hydrophobicity properties of Fe3O4 nanoparticles were modified by oleic acid (OA) to form Fe3O4@OA. Afterwards, graphene oxide (GO) nanosheets were functionalized with Fe3O4@OA nanocomposite to synthesize novel superhydrophobic nanosheets of Fe3O4@OA/GO. Synthesized Fe3O4@OA/GO nanocomposite was employed as a fast, recyclable, high performance, cost-effective, and environmentally friendly nanodemulsifier to eliminate oil from oily wastewater. Demulsification performance of synthesized GO-based nanodemulsifiers was measured using bottle test as a function of dosage of nanodemulsifier, temperature, pH, and s
Inhibition performance of noncovalent functionalization of carbon nanotubes (CNTs) with biodegradable gemini surfactants on mild steel surface in 2 M hydrochloric acid solution was examined by potentiodynamic polarization, electrochemical impedance spectroscopy and quantum chemical calculations. Ultraviolet–visible (UV–vis) spectroscopy, thermogravimetric analysis, Raman analysis, and zeta-potential (Z-potential) measurements are also applied to discuss the stability of studied solutions. Ester-containing cationic surfactants; monomeric betainate, dodecyl esterquat gemini (ET), and dodecyl betainate gemini (BT) were used as potentially superior noncovalent functionalization agents for CNT-based formulations. For the first time, the anti
In the present study, SiO2 nanoparticles (NP) were used for dehydration of crude oil. Also, in order to enhance the hydrophobicity and hydrophilicity of the nanoparticles, they were functionalized respectively with oleic acid (OA) and sodium dodecyl benzene sulfonate (SDBS) surfactant. Furthermore, graphene oxide (GO) was employed to synthesis GO-SiO2 nanocomposite as a superhydrophilic demulsifier. Nanodemulsifiers were characterized with scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), Brunauer–Emmett–Teller method (BET), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and zeta potential. Additionally, the performance of nanodemulsifier
To optimize the electrochemical performance and greater safety of Li-ion batteries (LIBs) in order to meet the market demands, an imidazolium-based ionic liquid (IL), namely 1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIm][PF6]) as a commercially available and most widely studied IL, was synthesized and applied as electrolyte additive in commercial 18650 LIBs. The different compositions of mixed electrolyte were prepared by adding 0–5?wt% of IL to the organic electrolyte. The electrochemical measurements were done using galvanostatic charge and discharge and electrochemical impedance spectroscopy, EIS, analyses to obtain the optimal percentage of additive resulting in highest cycleability and discharge capacity as t
Recently, nanoparticles have been used along with surfactants for enhancing oil recovery. Although the recent studies show that oil recovery is enhanced using nanoparticle/surfactant solutions, some effective parameters and mechanisms involved in the oil recovery have not yet been investigated. Therefore, the temperature effect on the stability of nanoparticle/surfactant solutions and ultimate oil recovery has been studied in this work, and the optimal concentrations of both SiO 2 nanoparticle and surfactant (sodium dodecyl sulfate) have been determined by the Central Composite Design method. In addition, the simultaneous effects of parameters and their interactions have been investigated. Study of the stability of the injected solutions in