Chemical Data Collections最新文献

In this problem, an unsteady magnetohydrodynamic heat and mass transfer study of hybrid nanofluid flow through porous media over a stretched sheet is performed. Additionally, the impacts of thermal radiation and chemical reactions are examined. Alumina (Al₂O₃) and titanium oxide (TiO₂) nanoparticles are mixed, and water is used as the base fluid to create hybrid nanoparticles. The strategy of nonlinear partial differential equations that govern the deconstruction of liquid flow has been diverted into an approach of ordinary differential equations via similitude changeovers and non-dimensional variables. Then, they were solved numerically utilizing the Rung-Kutta fourth-order strategy and miscellaneous firing techniques. The consequence of the derived physical characteristics on the disbandment of momentum, temperature, and concentration of micro particles has also been researched, employing illustrated representations to assign physical meanings to each parameter. This research was conducted to determine the effects of the physical parameters. It should be noted that heat and mass transfer on magnetohydrodynamic flows through porous media, considering the effect of chemical reactions, appears in many natural and artificial transport processes in several branches of science and engineering applications. This phenomenon plays a vital role in the chemical, power, and cooling industries for drying, chemical vapor deposition on surfaces, cooling of nuclear reactors, and petroleum industries. The effects of thermal radiation, mass, and heat transfer are used in many situations in biomedical engineering and aerospace engineering.

The current research work successfully presents facile synthesis, single crystal X-ray structure determination, Hirshfeld surface (HS) analysis, and Density functional theory (DFT) studies of 1-(4-methylbenzoyl)thiourea. Accordingly, the synthesized compound crystallized in triclinic P -1 space group with a = 7.3464 (5) Å, b = 8.2696 (5) Å, c = 8.5337 (5) Å, α = 88.349 (5)°, β = 72.206 (5)°, γ = 69.901 (6)°, Z = 2 and V = 461.89 (5) ų. In the crystal structure, the molecules are linked through intermolecular N—H···O, C—H···O, C—H···S and N—H···S bifurcated hydrogen bonds, enclosing R₂²(8), R₂²(14) and R₄⁴(11) ring motifs, into 2D network. HS analysis explored weak intermolecular interactions and indicated significant contributions responsible for crystal packing are H…H (41.0%), H…S/S…H (21.6%), H…C/C…H (12.7%) and H…O/O…H (9.9%) interactions, where hydrogen bonding and van der Waals contacts were dominant. Crystal voids analysis confirmed the absence of any large cavity within the packed crystal, suggesting higher mechanical stability of the crystal. Furthermore, analysıs of the electrostatic, dispersion and total energy frameworks augmented stabilization through electrostatic energy contribution. Moreover, optimized molecular structure, using DFT at B3LYP/6–311G(d,p) level was compared with the experimentally determined one. HOMO–LUMO energy gaps were determined and the molecular electrostatic potential (MESP) surfaces are calculated at B3LYP/6–31 G level to predict possible sites for electrophilic and nucleophilic attacks. DFT computations, through stable terminal HOMO and whole molecule LUMO spread, and significant polarity predicted amphoteric behavior of the synthesized 1-(4-methylbenzoyl)thiourea for its reaction with an electrophile or nucleophile.

We have synthesized eleven derivatives of 1,3-oxathio-2-imine, characterized through NMR, HREI-MS and evaluated against acetylcholinesterase and butyrylcholinesterase enzymes. All synthesized derivative showed good inhibitory potential, having IC₅₀ value ranged from 1.10 ± 0.05 to 23.20 ± 0.40 µM (AChE) and 2.30 ± 0.10 to 32.00 ± 0.80 µM (BuChE) as compare to standard drug Donepzil (IC₅₀ = 2.16 ± 0.12 & 4.5 ± 0.11 µM, respectively). In both case, derivative 7 (IC₅₀ = 1.10 ± 0.05 µM & 2.30 ± 0.10 µM, respectively) was found the most potent among the series. Structure activity relationship was carried out which mainly depend upon the nature, position, number and electron donating/withdrawing effect of the substituent/s on phenyl ring. Molecular docking was carried out to determine the binding attraction of the most potent derivatives with the active site of enzymes.

In this work, vapor-liquid equilibrium data were measured for the binary systems of 2-ethyl hexanol + 2-ethyl hexyl acrylate and acrylic acid + 2-ethyl hexyl acrylate at a constant pressure of 101.325 kPa. The VLE experimental analysis was conducted through a modified rose still. In order to verify the thermodynamic consistency of the VLE data, the Redlich-Kister area and Van Ness tests were performed. Regression was carried out on Aspen plus to correlate the vapor-liquid equilibrium data of the above systems with WILSON, NRTL and UNIQUAC activity coefficient models to obtain binary interaction parameters. The results of root mean square deviations (RMSD) and average absolute deviations (AAD) depicted that each model appropriately fitted the experimental VLE data since minimum deviations from experimental results were observed. Furthermore, the results of VLE experiments illustrated that the VLE data for each system was non-azeotropic.

This work reports a facile approach for synthesizing Cadmium @ Zinc oxide (x = 0, 5, 15 ml) nanocomposites (NCs) using leaf extracts of datura by co-precipitation method without varying the concentration of dopant followed by the comparison of their physical and optical properties. It is characterized by UV–vis, FTIR, PXRD, FESEM, EDAX, HRTEM, Raman spectroscopy, and PL analysis. PXD confirmed pure and crystallized with FCC with 32.35, 27.82, and 27.51 nm grain sizes. FTIR confirms that plant precursors acted as reducing and capping agents by stretching vibration at 546, 507, 487, and 433cm⁻¹. SEM and HRTEM data revealed the existence of spherical nanocomposites with nearly identical particle sizes. EDAX showed the existence of a nanocomposite of Cadmium @ Zinc oxide (x = 0, 5, 15 ml) nanocomposite. Raman spectra indicated that the Cd@ZnO NCs were crystallized in a hexagonal (wurtzite structure). A blue emission peak was observed in photoluminescence spectra. In the UV–Vis spectroscopy, band gaps of the synthesized nanocomposite are determined. By increasing extraction concentrations, the degradation efficiency of rhodamine-B dye increases up to 87.87 %. g-CZO nanocomposite effectively controlled both bacterial species Staphylococcus aureus and Klebsiella pneumonia in antimicrobial activity.

This study aimed to compare the essential oil yield and chemical composition of Artemisia herba-alba in the Anti-Atlas region, considering different harvest dates. The antibacterial and antifungal properties were also evaluated. Essential oils yields were 1.87 %, 1.85 %, and 2.35 % for the April, June and October harvests, respectively. Chromatographic analysis identified 21 compounds, with camphor, 1,8-cineole, and camphene as the main constituents. Artemisia herba-alba essential oils exhibited significant antibacterial and antifungal activities. The October-harvested oil showed notable antibacterial effects against Staphylococcus epidermidis (20 mm), while the June-collected essential oil demonstrated strong activity with a 20.66 mm inhibition zone against Acinobacter baumannii. Furthermore, the June-collected oil displayed significant antifungal activity with a 70.58 % inhibition index against Fusarium culmorum. Despite varying reducing powers with IC50 values, the antioxidant activity of the essential oils was relatively weaker compared to l-ascorbic acid, possibly due to the prevalence of non-phenolic compounds.

The present paper provides the physiochemical properties of binary systems of a bio-derived, eco-sustainable solvent furfuryl alcohol with 2-alkoxyethanols. Speed of ultrasound (U), density (ρ) of pure liquids and binaries of furfuryl alcohol with 2-methoxyethanol, 2-ethoxyethanol and 2-butoxyethanol have been measured at four temperatures from 303.15 K to 318.15 K (with interval as 5 K). From the measured experimental data, excess free length ($L_f^E$), excess volume per mole ($V_m^E$) and isentropic compressibility deviation (∆κ_s) have been calculated. For fitting the data of excess parameters, Redlich-Kister polynomial equation has been used and the corresponding standard deviation is computed. The variations in the parameters under investigation indicated molecular associations among the components of the mixture. Partial molar studies have approved these results. Further, FTIR spectral analysis has been undertaken to confirm the interactions of furfuryl alcohol and 2-alkoxyethanols. The FTIR analysis is well agreed with the thermodynamic findings.

Citrus reticulata Blanco essential oil was extracted using hydrodistillation, and its chemical profile was analyzed via GC/MS to give limonene as the major component (81.90 %). C. reticulata demonstrated remarkable antioxidant potential in DPPH (1,1-diphenyl-2-picrylhydrazyl) with in IC₅₀ (2.01 ± 0.01 mg/mL), ABTS (bleaching assay) (3.47 ± 0.02 mg/mL), and FRAP (iron reduction) (4.71 ± 0.43 mg/mL) assays, surpassing pure limonene. A synergistic effect was a key feature. In antibacterial tests, C. reticulata exhibited significant activity with a minimum inhibitory concentration (MIC) ranging from 12.5 to 25 µL/mL against four various bacteria (Staphylococcus aureus, Bacillus subtilis, Proteus mirabilis and Escherichia coli). Moreover, C. reticulata displayed impressive anti-corrosion capabilities, achieving up to 92.5 % protection at 1000 ppm using PDP, and 93.1 % using EIS and 90.1 % using WL. Langmuir adsorption isotherm analysis supported inhibitor adsorption, and potentiodynamic polarization curves confirmed its mixed-type action. These findings highlight C. reticulata's promise as a natural antioxidant, antimicrobial, and anti-corrosion agent.

A new series of thiophene-bearing thiourea derivatives (1–11) were synthesized and characterized through ¹³C NMR, ¹H NMR and HR-EIMS. The synthesized derivatives were screened against acetylcholinesterase, and butyrylcholinesterase inhibitory potentials. All derivatives display a variable degree of inhibitory potential ranging from 0.40 ± 0.05 to 26.40 ± 0.40 µM (against AChE) and 1.80 ± 0.10 to 36.80 ± 0.90 µM (against BuChE) as compared to standard drug donepezil (IC₅₀ = 2.16 ± 0.12 µM and 4.5 ± 0.11 µM, respectively). In both cases, among the series analogues 3, 5, 7, 9, and 10 showed many folds better activity than standard drug donepezil. Structure-activity relationship has been also established for all newly synthesized compounds, mainly based on substitution patterns on the phenyl ring. The binding interaction of the most active derivatives with the active site of enzymes was confirmed through a molecular docking study. To evaluate the stability of the protein-ligand complexes 10 ns MD simulation was carried out. The most potent compound such as compound 3 revealed great stability during the 10 ns simulation.

The density values were measured as a function of mole fraction [(ethylene glycol or glycerol] for binary liquid systems such as [ethylene glycol or glycerol + (hexane or cyclohexane or benzene] at a temperature between 283.15 K and 328.15 K and atmospheric pressure. Using density data, the values of molar volumes, excess molar volume, and apparent molar volumes were calculated. Further, excess molar volume was correlated with the Redlich–Kister model. It is observed that in all systems, density data was decreased with an increase in the temperature and also increased with the concentration of ethylene glycol and glycerol. Excess molar volume for all the binary systems were positive deviations over the entire composition range. Each system exhibited more positive at a higher temperature. The obtained results are discussed in terms of packing efficiency, $\pi -\text{OH}$ bonding, and dispersion forces.