A new type of nano-adsorbent zinc-silver nanoparticles ornamented by multi-walled carbon nanotubes (Zn-Ag MWCNT) was efficiently synthesized by double arc discharge using a newly designed rotating cylinder electrode. Zn-Ag MWCNT was characterized by different instrumental methods to get information about the sample shape, size, and crystallinity. Without irradiation, Zn-Ag MWCNT indicated significant potential for elimination against methylene blue (MB) which is dissolved in deionized water. When the adsorbent concentration was 0.1 g/L at normal 8 pH, the Zn-Ag MWCNTs were efficient in removing 97% of the MB from 40 mg/L that was dissolved in water for 10 min. The dye removal activity of (Zn-Ag) decorated MWCNTs was attributed to the influence of silver and zinc nanoparticles on the MWCNTs. Finally, this approach was both cost-effective and efficient.

The conventional solar still (CSS) unit faces challenges such as low productivity (P_d) and thermal efficiency (η_th) due to the limited temperature difference between the hot water and the cold interior glass cover surfaces (ΔT_w-gi). This study addresses these issues by introducing enhancements in the CSS unit, incorporating a v-corrugated-type basin, internal reflecting mirror, flat-plate solar collector (FPSC) still, and FPSC nanofluids. A v-corrugated-type basin, internal reflecting mirror, FPSC still, and FPSC nanofluids elicited a significant improvement in the distillate productivity (P_d) up to approximately 22.39%, 41.72%, 70.10%, and 104.13% compared to the CSS unit. This increase in the P_d is attributed mainly to a notable raise in the ΔT_w-gi, showing increments of around 34.33%, 52.32%, 77.37%, and 112.87% compared to the CSS unit. Moreover, a v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids substantially increased the average daily thermal efficiency (η_th), around 22.01%, 26.71%, 39.57%, and 56.21%, respectively. The results confirmed that integrating the v-corrugated basin, internal reflecting mirror, FPSC still, and FPSC nanofluids within a combined seawater distillation system can significantly enhance the performance of the CSS unit. These different combinations effectively raised the basin water temperature (T_w) and ΔT_w-gi, consequently improving the overall performance of the solar still unit.

Nanoparticles have attracted substantial attention for their diverse range of applications, particularly in biomedicine applications and drug delivery, owing to their unique properties. However, their tiny size facilitates easy cellular entry, which can also lead to interactions with cellular components, potentially resulting in toxicity and undesirable effects. In this study, a novel nanocomposite formulation was developed using biopolymers, specifically ethylcellulose and collagen, as capping and stabilizing agents to create bimetallic nanoparticles including TiO₂@Cr₂O₃ nanoparticles. Physicochemical and morphological analyses were carried out to validate the formulation’s structure. The obtained characteristics emphasized the presence of a nanostructure involving bimetallic nanoparticles. This formulation exhibited excellent biological activity, including high biocompatibility with Vero and WI38 cells at concentrations of 40.4 and 52 µg/mL, respectively, as well as effective anticancer activity with significant selectivity. The IC50 values were determined to be 19 and 22 µg/mL for MCF7 and A549 cells, respectively. The antimicrobial assessment revealed the highest MIC value for A. niger at 50 µg/mL, while the lowest MIC value was observed for Gram-positive bacteria at 3.12 µg/mL. Additionally, the nanocomposite demonstrated antioxidant activity at a low concentration of 1.5 µg/mL.

This work aimed to investigate temperature polarization (TP) and concentration polarization (CP), which affect solar-powered air-gap membrane distillation (SP-AGMD) system performance under various operating conditions. A mathematical model for the SP-AGMD system using the experimental results was performed to calculate the temperature polarization coefficient (τ), interface temperature (T_fm), and interface concentration (C_fm) at various salt concentrations (C_f), feed temperatures (T_f), and flow rates (M_f). The system of SP-AGMD was simulated using the TRNSYS program. An evacuated tube collector (ETC) with a 2.5 m² surface area was utilized for solar water heating. Electrical powering of cooler and circulation water pumps in the SP-AGMD system was provided using a photovoltaic system. Data were subjected to one-way analysis of variance (ANOVA) and Spearman’s correlation analysis to test the significant impact of operating conditions and polarization phenomena at p < 0.05. Statistical analysis showed that M_f induced a highly significant difference in the productivity (P_r) and heat-transfer (h_f) coefficients (p < 0.001) and a significant difference in τ (p < 0.05). Great F-ratios showed that M_f is the most influential parameter. P_r was enhanced by 99% and 146%, with increasing T_f (60 °C) and M_f (12 L/h), respectively, at a stable salt concentration (C_f) of 0.5% and a cooling temperature (T_c) of 20 °C. Also, the temperature increased to 85 °C when solar radiation reached 1002 W/m² during summer. The inlet heat temperature of AGMD increased to 73 °C, and the P_r reached 1.62 kg/(m²·h).

Nowadays, choosing a corrosion inhibitor is not only based on efficiency, but must also consider the toxicity of the compound, the impact on the environment, and, obviously, the regulations in the field. In the last two decades, a special class of substances has begun to be studied, namely polyoxometalates (POMs). Their electronic properties and redox characteristics make the polyoxometalates potential candidates to be used in many electrochemical processes, and as potential corrosion inhibitors. Electrochemical methods such as a Tafel extrapolation plot, chronopotentiometry, or gravimetry have been used to establish the capacity of corrosion inhibition of S235 and SS304 steels in the presence of phosphovanadomolibdate acid (@PMoV) and phosphovanadotungstate acid (@PWV) in 0.5 M sulphuric acid solution. The inhibition efficiency for S235 steel is about 90.6% for @PMoV, and 69.5% for @PWV after 24 h of immersion. In the case of SS304 steel, polyoxometalates have similar effects: the inhibition degree, as a function of Flade potential, is 4.66 for @PMoV; better than 3.26 for @PWV, with both proving the passivant effect.

In this study, the author improved and modified g-C₃N₄ by doping it with the metals Ag and Cu, which changed the photochemical properties of g-C₃N₄, narrowed the band gap, and improved the photocatalytic performance regarding quantum efficiency. Organic hydrocarbons such as 1,2-dichloroethane (DCE) are very stable prepared materials produced as intermediates to obtain polyvinyl chloride, and the prepared photo-catalyst is an innovative method for extreme decomposition of chlorinated hydrocarbons. However, some significant results were obtained using different analysis techniques. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) showed that the addition of Ag and Cu-NPS partially altered the structure of pure graphitic carbon nitride (g-C₃N₄-Pure). Scanning electron microscopy (TEM) analysis revealed that the morphological features of Ag-Cu/g-C₃N₄ contain quantum dots of Ag and Cu nanoparticles in addition to 2d-g-C₃N₄. The better separation of the photo-generated charge carriers is attributed to better photoactivity in the case of 0.3 g Ag-Cu/g-C₃N₄ with a reaction time of less than 30 min. Furthermore, the Ag-Cu/g-C₃N₄ recycling experiment showed that the catalyst remained stable after three stages of the pyrolysis experimental cycle. Another clear indicator of DCE degradation is the measurement using the titration of the Cl ions released by the decomposition.