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Abstract The palladium anchored to BisPyP@bilayer-SiO2@NMP organic–inorganic hybrid was employed as an effective and recyclable organometallic catalyst in Suzuki and Stille C–C coupling reactions. The structure of this magnetic nanocatalyst was determined using various techniques such as SEM, TEM, FT-IR, EDS, ICP-OES, VSM, N2 adsorption–desorption isotherms, XRD, and TGA. In both of the mentioned coupling paths, the yields of the products were very favorable and ranged from 90 to 98%. Also, they had significant features compared to previous reports, such as very short reaction time (5–15 and 7–20 min respectively in the Suzuki and Stille reactions), easy work-up, broad substrate scope, ease of separation of the catalyst using a magnet, suitable reproducibility of the catalyst in 6 runs, heterogeneous nature of the catalyst and not washing it during consecutive runs with confirmation of hot filtration and ICP-OES methods.

Abstract At first, an organometallic catalyst namely, Pd-DPyE@MCM-41@MNP was prepared through magnetic (Fe3O4) nanoparticles-doped into channels of mesoporous silica MCM-41 and then, anchoring a novel complex composed of di(4-pyridyl)ethylene and palladium on the inner surface of the support. This immobilized catalyst was successfully identified via VSM, ICP-OES, TEM, FTIR, TGA, SEM, BET, XRD, EDX and elemental mapping analyses. After that, it was used as a versatile, heterogeneous, and magnetically reproducible catalyst in the generation of N,N′-alkylidene bisamides (1a-13a, 8–20 min, 90–98%, 50 °C, solvent-free) and Suzuki–Miyaura coupling (SMC) reaction derivatives (1b-26b, 10–140 min, 86–98%, 60 °C, PEG-400). The VSM plot of Pd-DPyE@MCM-41@MNP displays that this nanocatalyst can be easily recycled by applying an external magnetic field. In both synthetic paths, this nanocatalyst was reused at least seven times without palladium leaching and significantly reducing its catalytic performance. Also, stability and heterogeneous nature of catalyst were approved via ICP-OES technique and hot filtration test.

Abstract In this study, a CoO–Fe2O3/SiO2/TiO2 (CIST) nanocomposite was synthesized and utilized as an adsorbent to remove methylene blue (MB), malachite green (MG), and copper (Cu) from aqueous environments. The synthesized nanocomposite was characterized using field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Input parameters included pH (3–10), contact time (10–30 min), adsorbent amount (0.01–0.03 g), and pollutant concentration (20–60 mg L−1). The effects of these parameters on the removal process efficiency were modeled and optimized using the response surface methodology (RSM) based on the Box–Behnken design (BBD). The RSM-BBD method demonstrated the capability to develop a second-degree polynomial model with high validity (R2 ˃ 0.99) for the removal process. The optimization results using the RSM-BBD method revealed a removal efficiency of 98.01%, 93.06%, and 88.26% for MB, MG, and Cu, respectively, under optimal conditions. These conditions were a pH of 6, contact time of 10 min, adsorbent amount of 0.025 g, and concentration of 20 mg L−1. The synthesized adsorbent was recovered through five consecutive adsorption–desorption cycles using hydrochloric acid. The results showed an approximately 12% reduction from the first to the seventh cycle. Also, MB, MG, and Cu removal from real water samples in optimal conditions was achieved in the range of 81.69–98.18%. This study demonstrates the potential use of CIST nanocomposite as an accessible and reusable option for removing MB, MG, and Cu pollutants from aquatic environments.

In this study, Co3O4 nanoparticles were used as nanocatalyst for two different series of nitrogen-containing heterocyclic compounds, including pyrrole (Pyo) derivatives and pyrano [2, 3-c]pyrazole (Pya[2, 3-c]Pyz) derivatives. In the synthesis of derivatives, using 15 mol% and 10 mol% of the catalyst for Pyo derivatives and Pya[2, 3-c]Pyz derivatives, respectively, an efficiency between 83% and 96%, were observed. In addition, novel derivatives of Pyo and Pya[2,3-c]Pyz were synthesized and their structures were confirmed. In general, the advantages of using cobalt nanoparticles compared to previous reports include the synthesis of new derivatives, lower temperature used in the synthesis of derivatives, shorter synthesis time and high efficiency. The biological properties of the synthesized products, such as antibacterial, antifungal, and antioxidant properties, were tested and investigated. In antibacterial and antifungal tests, IZD, MIC, MBC, and MFC were measured and reported. In antioxidant activity, IC50 was calculated and reported. High reusability, green and environmentally friendly, synthesis of new derivatives and synthesis of products with higher efficiency and shorter time were the important benefits of using cobalt nanoparticles as a catalyst. In antioxidant tests, the IC50 for synthesized Pyo derivatives and Pya[2, 3-c] Pyz derivatives were between 12.2 and 13.71 μg/mL, and 16.18–17.75 μg/mL, respectively. In antimicrobial testes, the MIC for synthesized Pyo derivatives and Pya[2, 3-c]Pyz derivatives were between 2 and 4,096 μg/mL, and 2–2048 μg/mL, respectively. The results showed that the antioxidant property of Pyo derivatives were more than Pya[2, 3-c] Pyz derivatives, but the antimicrobial effect of Pya[2,3-c] Pyz derivatives were more than Pyo derivatives. The antioxidant results proved that the activity of Pyo derivatives and Pya[2, 3-c] Pyz derivatives does not depend on the substitutions of the derivatives and is close to each other. Therefore, based on this, a proposed mechanism for stability of DPPH by Pyo derivatives and Pya[2, 3-c] Pyz derivatives were suggested. Finally, based on the more stable resonance structures of Pyo derivatives, compared to Pya[2, 3-c] Pyz derivatives, its high antioxidant property was justified. Pya[2, 3-c] Pyz derivatives has two heterocyclic rings connected together pyrano and pyrazole, but Pyo derivatives has only one heterocyclic ring (pyrrole). So high antimicrobial property of Pya[2, 3-c] Pyz derivatives compared to Pyo derivatives can be attributed to having two bioactive heterocyclic rings.

BackgroundIt has been suggested that metabolic syndrome (MetS) accelerates the aging process, potentially contributing to the development of age-related complications. Available studies examining the relation of MetS to telomere length (TL), a putative biological marker of aging, have yielded inconclusive findings. This meta-analysis was performed to investigate the association between MetS and TL.MethodsA comprehensive systematic search was conducted in PubMed and Scopus databases to identify relevant literature published up to February 2024. Standard mean difference (SMD) and standardized beta coefficient (β) with their 95% confidence intervals (CI) were used as effect sizes to measure the associations using the random effects model.ResultsA total of nine studies, comprising a total sample size of 8,606 participants, were eligible for the meta-analysis. No significant difference in mean TL was found between patients with and without MetS (SMD = −0.03, 95%CI = −0.17 to 0.10), with a significant heterogeneity across the studies (I2 = 89.7.0%, p ≤ 0.001). In contrast, it was revealed that MetS is negatively related to TL (β = −0.08, 95%CI = −0.15 to −0.004). In the subgroup analysis, this finding was supported by the International Diabetes Federation (IDF) definition of MetS.ConclusionThis meta-analysis highlighted that MetS may be linked to a shorter TL. Additional studies are required to confirm this finding.

The Lattice Boltzmann Method (LBM) is one of the suggested numerical approaches that has been shown to accurately estimate the increase in heat transfer caused by nanofluids. Several approaches to the prediction of the characteristics of nanofluids are investigated, and it is shown to what degree the classical models are accurate representations of the experimental data. The first thing that was done in this study was to explain the thermophysical parameters of the Ethylene Glycol (EG)-iron nanofluid that was employed. The effect of the Rayleigh number, the volume fraction of nanoparticles (φ), and the cavity angle (θ) on the isotherms and the average Nusselt number (Nuavg) are investigated. Finally, the effect of the adiabatic fin on the flow is investigated, and it is demonstrated in which scenario the adiabatic vane will be the most effective. The findings demonstrate that raising the Rayleigh number to 105 and 106 causes the heat to be transferred under the adiabatic fin. This finding suggests that the buoyancy force has a stronger influence on the heat transfer process when it is carried out close to the source of the cold. In general, if the Rayleigh number is increased, the rate of heat transfer in the fluid will rise as well. The Nu avg is increased by 44 % when the Ra number is increased from 103 to 105, and it is increased by 118 % when the Ra number is increased from 105 to 106. The chances of heat entering the cold source are reduced when the adiabatic fin is longer and situated lower. There is a wider cold zone within the hollow when Lf = 80 and Hf = 20, indicating that less heat is entering the cold source.

Abstract In this study, the Fe3O4/rGO/Ag magnetic nanocomposite was synthesized and employed as an adsorbent for the removal of tetracycline (TC), crystal violet (CV), and methylene blue (MB) from water samples. The influential parameters in the removal process were identified and optimized using response surface methodology (RSM). Characterization of the product was performed through field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), vibrating-sample magnetometer (VSM), and X-ray diffraction (XRD) analysis. XRD and SEM analysis revealed the successful synthesis of the Fe3O4/rGO/Ag nanocomposite. EDX analysis elucidated the accuracy and clarity of the chemical composition of the magnetic nanocomposite structure. Additionally, the separation of the nano-adsorbent from the solution can be achieved using a magnetic field. Maximum removal of analytes was obtained at pH of 6, amount of nanocomposite 0.014 g, ultrasonic time of 8 min and concentration of 21 mg L−1. Under optimal conditions, the removal efficiencies for TC, CV, and MB were 91.33, 95.82, and 98.19%, respectively. Also, it was observed that after each adsorption–desorption cycle, Fe3O4/rGO/Ag magnetic nanocomposite had good stability to remove TC, CV, and MB. Achieving nearly 98% removal efficiency in optimal conditions showed that Fe3O4/rGO/Ag magnetic nanocomposite is an effective adsorbent for removing TC, CV, and MB from wastewater samples.

There are several parameters in designing undersurface vessel forms, the most important of which is the hull's total strength, which includes the strength of the hull and its attachments. According to studies, 70 % of the total strength of the vessels is related to their hull only without attachments. The hull has three major parts: nose, cylinder, and heel. The advanced vessels' architecture has a parallel shape (cylinder shape). This cylindrical part is important in examining the used volume by pilots and vessel equipment. This paper uses the CFD method to examine the vessel's shape, and the resistive force and volumetric-aqueous efficiencies are extracted. An optimum profile is extracted by the values of resistive force and volumetric-aqueous efficiencies. The results indicate the significant effect of the hull form on the hydro-acoustic noise of the hull. In other words, by optimizing the hydrodynamic form of the hull, the noise propagation can be reduced as much as possible. Also, the linear slope of the optimized hull is not optimized more than the hull. This means that the turbulence caused by the optimized hull has a higher damping potential.

In this study, choline chloride/urea was used as a green deep eutectic solvent in the three-component reaction of hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrazole derivatives, and in the four-component reaction of methyl/ethyl acetoacetate, hydrazine/phenylhydrazine, malononitrile, and aromatic aldehydes for synthesizing pyrano[2,3-c]pyrazole derivatives. Elemental analysis, 1H, and 13C NMR spectroscopy were used to confirm the structure of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives. The antimicrobial effects of the synthesized pyrazole and pyrano[2,3-c] pyrazole derivatives were investigated. In antimicrobial tests, instructions from clinical and laboratory standards institutes were used. Antimicrobial study was done on pathogenic gram-positive and gram-negative species, and specialized aquatic strains and fungal species. Using choline chloride/urea, novel pyrazole derivatives and pyrano[2,3-c]pyrazole derivatives were synthesized, and other derivatives were synthesized with higher efficiency in less time than some previously reported methods. MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) obtained for derivatives were higher than some antibiotic drugs. Synthesis and reports of new derivatives of pyrazole and pyrano[2,3-c]pyrazole, and investigation and reports of their antimicrobial properties on gram-positive, gram-negative, and specialized aquatic and fungal species are among the novel and important findings of this study.

Recently, nanoscience, especially metal–organic frameworks (MOFs), has been used to increase the effectiveness and properties of drugs. In this study, by using microwave irradiation; penicillin, which is a known antibiotic; and copper metal–organic frameworks (Cu-MOFs), a new penicillinoate@copper metal–organic framework (penicillinoate@Cu-MOF) was synthesized. The structure and characterization of the newly synthesized compound were determined using FT-IR spectrums, EDAX analysis, elemental analysis, XRD patterns, SEM images, nitrogen adsorption/desorption curves, and TGA curve. Then, its antimicrobial effects were evaluated on numerous Gram-positive and Gram-negative bacterial strains and were compared with those of penicillin and gentamicin. In continuation of the biological activities, antioxidant tests were performed on the compounds using the DPPH method. For biological activities, the synthesized penicillinoate@Cu-MOF is much more effective than penicillin and Cu-MOF. The loading of penicillin on the nanostructure and the presence of copper in the final composition can be attributed to the high antibiotic properties of the synthesized composition.

This study aims to optimize the economic thermodynamics of a flat plate solar collector and investigate transient heat transfer. This study focuses on modeling and optimization under unfavorable radiation conditions. The method employed here is optimization using a multi-objective genetic algorithm with the assistance of MATLAB software. The key components include objective functions, constraints, and design variables, which are the collector efficiency and the annual total price. The results indicate that increasing the length of the collector has a negative impact on the thermodynamic efficiency and increases the total annual price. Conversely, increasing the width of the collector initially improves the thermodynamic efficiency but then decreases it while also increasing the total annual price. Furthermore, increasing the number of pipes leads to a decrease in the total annual price and an initial increase followed by a decrease in the thermodynamic efficiency. The research was conducted over four different days.

The present study aimed to remove sulfonamide antibiotics from water samples using magnetic Fe3O4-bentonite nanocomposite (Fe3O4-Bt) as an adsorbent. The adsorbent has a surface area of 74.27 m2 g-1, a pore size of 87.53 nm, and a pore volume of 0.146 cm3 g-1. A central composite design (CCD) matrix was employed to model and optimize the process. The optimal conditions for removing sulfonamide antibiotics were determined using Fe3O4-Bt adsorbent at an antibiotic concentration of 20 mg L-1, the amount of nanoparticles of 0.23 g, pH of 6, and ultrasonication time of 17 min. The reusability study of the Fe3O4-Bt adsorbent showed that the Fe3O4-Bt could be used five times in adsorption/desorption processes. Also, applying the Fe3O4-Bt adsorbent on real samples revealed that Fe3O4-Bt adsorbent could remove sulfonamide antibiotics in the range of 86.85–97.47% with RSD (n = 5)

Carbon Capture and Storage (CCS) field is growing rapidly as a means to mitigate the accumulation of greenhouse gas emissions. However, the geomechanical stability of CCS systems, particularly related to bearing capacity, remains a critical challenge that requires accurate prediction models. In this research paper, we investigate the efficacy of employing an Autoregressive Deep Neural Network (ARDNN) algorithm to predict the geomechanical bearing capacity in CCS systems through shear wave velocity prediction as an index for bearing capacity evaluation of deep rock formations. The model utilizes a dataset consisting of 23,000 data points to train and test the ARDNN algorithm. Its scalability, use of deep learning techniques, automatic feature extraction, adaptability to changes in data, and versatility in various prediction tasks make it an attractive option for accurate predictions. The results demonstrate exceptional performance, as evidenced by an R-squared value of 0.9906 and a mean squared error of 0.0438 for the test data compared to the measured data. This research has significant practical implications for effectively predicting geomechanical stability in CCS systems, thus mitigating potential risks associated with their operation.

Background: By considering the importance and role of soil in the health of humanity, it is important to remove the presence of harmful compounds, such as phenol. Methods: In this study, four types of soil and leaf samples were collected from Kerman, Iran, and the amounts of heterotrophic and degradation bacteria were determined using the serial dilution and most probable number (MPN) methods. The amount of removed phenol was investigated using the Gibbs method with different concentrations of phenol. Then, an isolate with the highest percentage of phenol degradation was identified as the superior strain using 16 sRNA sequencing. The effects of the different factors, such as the carbon source (1% molasses and 1 g glucose), nitrogen source (0.1 g yeast extract), mixed culture, and time (14 and 28 days), on the biodegradation ability of the superior strain was investigated. Results: A total of 18 bacterial strains were isolated from the samples. Isolate B3 had the highest rate (75%) of phenol degradation, at a concentration of 1000 ppm, meaning it was identified as the superior strain. The molecular analysis results identified this isolate as the Comamonas testosteroni strain F4. This bacterium can degrade 89% of the phenol at 30 °C, 180 rpm, and 800 ppm over 28 days. C. testosteroni did not show a favorable phenol degradation ability in the presence of the investigated carbon sources, while this ability was also reduced in mixed cultures. Conclusions: C. testosteroni bacterial strain isolated from soil samples of pistachio orchards in Kerman, Iran, has a favorable ability to biodegrade phenol.