The dynamics of a water nano-droplet on a flexible graphene sheet, in the presence of constant and alternative electric fields with various amplitudes and frequencies, was considered using a molecular dynamics method. It was found that because the water molecules respond to electric field, the nano-droplet elongates in the field direction for a field amplitude larger than 0.08 V Å, which is stronger than the predicted value from the Young-Laplace equation. This difference can be described by considering the van der Waals attractions between the droplet molecules and the substrate, which can be calculated by modifying the Young-Laplace equation. Furthermore, under the influence of an alternating field over the GHz frequency range, it was shown that the droplet shape will not change above a threshold frequency, which depends on the relaxation time of the water dipole.

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Multilayer graphene membranes could be considered as an efficient membrane in water desalination processes based on the reverse osmosis (RO) method. In this study, we designed multilayer graphene channels using the molecular dynamics (MD) simulation approach. The effects of different parameters, such as channel width and length, and the pressure on the operation of the designed channels were examined, in the absence and presence of electric fields with various amplitudes and directions. The results indicated that the ion separation and water flow through the channels were modified under the application of the electric fields. Additionally, it has been shown that salt rejection and water flow could be controlled by the channel's structural parameters mentioned above. The obtained results of this study at the molecular level can improve the knowledge of designing membranes for water purification processes. Graphical abstract Using MD method a multilayer graphene membrane was designed to separate Na and Cl ions from a NaCl solution by the aid of external electric field, which can significantly effect the membrane operation.

CuO nano-structures were prepared in Rosmarinus Officinalis leaves extract medium via a green bio-chemical method and were used for the one-pot synthesis of dihydropyrano [3,2-c] chromene derivatives. This procedure is very simple and the products were synthesized in high to excellent yields.

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Water flow through graphene-based channels can be described as a function of h and p by a third order polynomial curve.

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The synthesis of oxides has a significant role in their improved properties. This is why a green method is used to gain stable oxide nanoparticles. Zn2+ doped magnesium oxide (MgO) nanoparticles were synthesized through a green method, extracting Aloe vera latex media. The green method has the advantages of being a cost-effective, innocuous, eco-friendly method. Firstly, thanks to the structure of Aloe vera latex, its extract has an important role in morphology, and crystal size of MgO structure, which leads to homogenous nanoparticles dispersion. The elliptical particles with ranges from 45 nm to 65 nm were observed by scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). Furthermore, the effect of calcination temperature was investigated, showing that increasing calcination temperature made larger particles with sharper peaks in X-ray diffraction (XRD) analysis. The strain value (ε) and crystallite size by Williamson-Hall (nm), dislocation density, and crystallinity index were evaluated. Finally, energy dispersive X-ray spectroscopy (EDS) confirmed the doping of Zn2+ in MgO nanoparticles. Fourier transform infrared (FT-IR) and HRTEM analyses were also used.