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Nanosheets (CC-BC3-C3N) as a carrier for favipiravir drug. [Display omitted] • The present study evaluated favipiravir drug adsorption onto bare graphene, NC 3 , and BC 3 nanosheets. • QTAIM analysis was carried out to examine the intermolecular interactions of the complexes. • The findings demonstrated the potential of the graphene-like BC 3 flake to be employed for drug delivery purposes. Two-dimensional nanostructures have recently been of great interest to researchers in drug delivery applications. Researchers developed two-dimensional NC3 and BC3 flake layers. The present work evaluates the drug delivery potential of pristine graphene and these two flakes through density functional theory (DFT) PBE/6-311+G (2d, p) mainly to measure their interactions with favipiravir drug. The results demonstrated that the aqueous phase had greater negative adsorption energy values. This indicated that these two flakes could undergo solubility improvement and be modified in drug interaction within the solvent phase. Moreover, the ultraviolent-visible (UV–vis) spectra results revealed a blue shift in the electronic spectral of the complexes to lower wavelengths. To further understand the binding characteristics of these systems with favipiravir (FP), the present study used atoms-in-molecules (AIM) analysis. The electrostatic properties of the bonding of BC3 flake and FP were determined. Finally, the graphene-like BC3 flake was found to be capable of serving as a promising carrier to deliver the FP drug. [ABSTRACT FROM AUTHOR]

Air pollution is known as one of the most important causes of death in the whole world. Therefore, pollution reduction to achieve clean air was noticed by everyone. This way, using nanotechnology to control air and monitor is a novel approach. This paper investigates the effect of the number of graphene nano-pores on the SiO 2 separation from the H 2 O vapour in the presence of an external electric field with the magnitude of 0.01 V/Å using the molecular dynamics (MD) method. The electric field affects the charged particles and causes disturbance in the structure. It also prevents SiO 2 nanoparticles from passing through the graphene nanosheet. Also, the presence of carbon nanosheets acts as a membrane and affects the diffusion of water in the nanostructure. So, the results show that in the presence of a nano-pore, the number of H 2 O molecules reaches to 496 and 568 in reservoirs 2 and 3. Also, the number of SiO 2 nanoparticles reaches 10 and 4 in reservoirs 2 and 3. This shows that in reservoirs 2 and 3, about 80% and 60% of the SiO 2 nanoparticles are separated. As mentioned before, the electric field prevents the passage of SiO 2 nanoparticles through the graphene nanosheet. As the number of graphene nano-pores increases by 2, 3, 4, and 5, the number of passing water molecules increases. Considering that the number of graphene nano-pores has increased and the movement path of particles has increased, the number of passing particles almost increases. However, the electric field prevents the passage of SiO 2 nanoparticles. According to the results, the suggested setup can be employed for designing highly efficient nanostructured membranes for air purification and monitoring. [Display omitted] [ABSTRACT FROM AUTHOR]

The single-flash geothermal cycle (SFGC) is not without its limitations, featuring drawbacks like diminished efficiency, restricted power generation capacity, and the incapability to yield multiple outputs concurrently. Furthermore, the SFGC requires a substantial water supply, potentially leading to adverse environmental consequences. In a concerted effort to enhance overall performance and facilitate the concurrent production of multiple valuable products, this study introduces a multigeneration system (MGS). By integrating additional subsystems into the SFGC framework, including a branched GAX cycle enabled by a thermoelectric generator (TEG), a domestic water heater (DWH), and a reverse osmosis unit, the objective is to surmount these limitations effectively. A thermodynamic and exergoeconomic analysis of the system is conducted and a bi-objective optimization is employed to minimize system cost and maximize exergy efficiency. The parametric study reveals that when degassing ranges are in the range of 0.2–0.37, the system product cost varies from $27.07/MWh to $28.44/MWh. In the optimized scenario there is a decrease of 67.7% in cooling provided by the system. This leads to an increase of 3.5% in generated electricity and a 3% increase in water purification compared to the base scenario. Through optimization the exergy efficiency of the system improves from 61.84% to 62.90% while the multigeneration gain output ratio (MGOR) decreases from 1.40 to 1.38. [ABSTRACT FROM AUTHOR]

The paper presents the design and technological fabrication process of Yin or Yang-shaped, micron-sized electromechanical system (MEMS) elements displaying asymmetric hollow cylinders with two different curvatures of the cylinder shell. By adapting the process steps, two neighboring shutter MEMS elements can either be attached to each other to create asymmetric hollow cylinders or remain disconnected to form curled cylindrical or ellipsoidal tubes or tube fractions. A novel 3D self-organization process has been developed to connect two neighboring shutter elements, exploiting surface tension forces via a sequential drying process. The process conditions have been analyzed and optimized to fabricate the two different geometries of the MEMS elements. The resulting MEMS system elements were characterized by focused ion beam and scanning electron microscopy. The contribution of Casimir force, van der Waals force, and other physical interfacial forces are discussed in the formation of the asymmetric hollow cylinders. [ABSTRACT FROM AUTHOR]

In this study, we investigated the process of preconcentrate and determine trace amounts of Auramine O (AO) and methylene blue (MB) dyes in environmental water samples. For this purpose, the ultrasound-assisted dispersive-magnetic nanocomposites-solid-phase microextraction (UA-DMNSPME) method was performed to extract AO and MB from aqueous samples by applying magnesium oxide nanoparticles (MgO-NPs). The proposed technique is low-cost, facile, fast, and compatible with many existing instrumental methods. Parameters affecting the extraction of AO and MB were optimized using response surface methodology (RSM). Short extraction time, low experimental tests, low consumption of organic solvent, low limits of detection (LOD), and high preconcentration factor (PF) was the advantages of method. The PF was 44.5, and LOD for AO and MB was 0.33 ng mL−1 and 1.66 ng mL−1, respectively. The linear range of this method for AO and MB were 1–1000 ng mL−1 and 5–2000 ng mL−1, respectively. In addition, the relative standard deviation (RSD; n = 5) of the mentioned analytes was between 2.9% and 3.1%. The adsorption–desorption studies showed that the efficiency of adsorbent extraction had not declined significantly up to 6 recycling runs, and the adsorbent could be used several times. The interference studies revealed that the presence of different ions did not interfere substantially with the extraction and determination of AO and MB. Therefore, UA-DMNSPME-UV/Vis method can be proposed as an efficient method for preconcentration and extraction of AO and MB from water and wastewater samples. [ABSTRACT FROM AUTHOR]

• Initial study by ultrasound-assisted dispersive solid-phase extraction using magnesium ferrite as a magnetic adsorbent. • The spectrophotometric method was successfully applied. • Response surface methodology was used to optimize the extraction of dyes. • The proposed method was sensitive, fast, inexpensive, reliable, simple, and eco-friendly. This study aimed to determine of malachite green (MG) and auramine O (AO) dyes in different environmental water samples. For this purpose, MG and AO dyes were pre-concentrated by ultrasound-assisted dispersive solid-phase extraction (UA-DSPE) and measured by spectrophotometry. Magnesium ferrite (MgFO) was applied as a magnetic adsorbent in the UA-DSPE-UV/Vis method. The effect of different parameters on the dye extraction efficiency, including pH of the solution, sorbent mass, sample volume, ultrasound frequencies, irradiation time, and type and volume of eluent, were investigated. In addition, response surface methodology (RSM) approach-based central composite design (CCD) was used to design and optimize parameters affecting the process. Analysis of variance (ANOVA) results based on high F-values, low p-values, coefficient of determination (R2 > 0.99), and adjusted-R2 (R2adj > 0.99) revealed that the quadratic model was the best model for defining the interaction of the studied variables. The calibration curve, the limit of detection (LOD), and relative standard deviation (RSD, n = 5) for MG and AO dyes were 1–800 ng mL−1 and 3–1200 ng mL−1, 0.33 ng mL−1 and 1 ng mL−1, and 3.2% and 2.8%, respectively. The effect of some external species (including cations and anions) on the determination of MG and AO dye was investigated. The results revealed that adding different ions does not significantly interfere with determining MG and AO dyes. The reusability of the MgFO adsorbent showed that it could be reused for up to 7 cycles, maintaining its high efficiency in the extraction of MG and AO dyes. Moreover, the proposed method was used for the extraction of MG and AO dyes from different water samples. The obtained extraction efficiency was in the range of 95.37–99.54%. [ABSTRACT FROM AUTHOR]

Zeolites are among the most popular porous solids for hydrogen storage. Hydrogen attaches to the surface and microporous structure of zeolites. The literature mainly inspected the hydrogen adsorption capacity of zeolites (HACZ) experimentally and paid little attention to its modeling. Furthermore, there is no tool to compare/reveal the role of surface and pore characteristics of zeolites in hydrogen storage. This work applies several well-established artificial intelligence techniques to correlate the HACZ to surface and pore characteristics of zeolites, pressure, and temperature. The topology-tuned multi-layer perceptron neural network is the best model to simulate the hydrogen storage of fourteen systems (NH 4 Y, X, and ZSM-5). This model predicts the HACZ of a vast experimental databank with a regression coefficient of 0.99875 and an absolute average relative deviation of 6.43%. Results approve that the role of the BET surface area of zeolites on the HACZ is more vital than the pore volume. • Effect of surface and pore properties of zeolites on hydrogen storage is compared. • BET surface area of zeolites is more vital than pore volume for the H 2 storage. • Machine learning models are applied to simulate H 2 loading capacity of zeolites. • H 2 storage increases by increasing zeolites' BET surface area and total pore volume. • The proposed model predictions are interpretable by the Chahine's rule. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-doped BC 3 nanosheet may be highly sensitive carbonyl sulfide gas sensor. • The carbonyl sulfide adsorption reduces the HOMO-LUMO energy gap of the Cu-doped BC 3 from 2.52 to 1.52 eV (∼-39.7%). • A short recovery time of 13.3 s is found for the carbonyl sulfide desorption. We explored the adsorption of carbonyl sulfide (COS) on a pristine and a Cu-doped graphene-like boron carbide nano-sheet (PBCNS and DBCNS) via density functional theory computations. When COS approached the BCNS, its adsorption released an energy of 6.8 to 7.5 kcal/mol, which demonstrates the weak nature of the adsorption. Furthermore, there was no appreciable alteration in the electronic characteristics of the nano-sheet. Cu-doping enhances the performance of the BCNS, improving it reactivity and sensitivity towards COS. The calculations demonstrated the adsorption of COS caused a reduction in the energy of the HOMO-LUMO gap of the DBCNS from 2.52 to 1.52 eV (∼-39.7%), suggesting a rise in the electrical conductance of the nano-sheet. Thus, DBCNS was capable of generating signals when the COS molecules approached, showing the promising nature of this nano-sheet as a sensor. The recovery time for DBCNS was 13.3 s , which was short. [ABSTRACT FROM AUTHOR]