Chemical Data Collections最新文献

In this study, zinc oxide-hydroxyapatite (ZnO-HAp) nanocomposite was prepared via hydrothermal method for the photodegradation of levofloxacin. The effect of different HAp loadings of the nanocomposite showed that 90 % ZnOHAp has the highest % degradation toward levofloxacin (88.65 %). Then, the 90 % ZnOHAp was characterized with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) which a revealed rod shaped ZnO (70–150 nm) adsorbed on hydroxyapatite plates (500 nm). X-ray diffraction (XRD) and Infrared spectroscopy (FTIR-ATR) confirmed the successful synthesis of ZnOHAp. The 90 % ZnOHAp nanocomposite was used as a photocatalyst to degrade aqueous levofloxacin under UV irradiation. Optimization of the photodegradation was performed using the response surface methodology (Box Behnken model). Analysis of variance of the model showed good predictability and goodness of fit (R² = 99.05 %, adjusted R² = 97.33 %, predicted R² = 91.54 %). The optimum parameters generated were 1.32 g/L catalyst dose, 4 ppm levofloxacin, pH 7.7 and the predicted photodegradation response was 99.99 % using 90 % ZnOHAp. Subsequent experimental verification yielded an actual % degradation of 91.69 % under the obtained optimized conditions. Additionally, the 90 % ZnOHAp phtocatalyst exhibited good recyclability over four cycles.

A new library of different types of aryl ring attached pyrazole-thiazole-oxazoles (11a-j) was prepared and their structures were characterized by ¹HNMR, ¹³CNMR and mass spectral data. Further, these compounds were evaluated for anticancer effects towards a panel of four human cancer cell lines including SiHa (cervix cancer), A549 (lung cancer), MCF-7 (breast cancer) and Colo-205 (colon cancer) by the MTT method, with etoposide used as a reference drug. Most of the tested compounds exhibited good anticancer activity with IC₅₀ values ranging from 0.13±0.046 µM to 18.6 ± 6.34 µM and the reference drug showed values ranging from 0.14 ± 0.017 µM to 3.11±0.11 µM, respectively. Among these compounds 11e, 11f, 11 g and 11 h displayed more potent anticancer activity as etoposide. All compounds showed selective cytotoxicity against cancer cells but not against normal Vero cells (IC₅₀ = >24 µM), justifying the designing approach to develop a selective anticancer agent.

Quercetin (QT) is found to be a green source of anti-corrosion additive for M-S protection in 0.5 M sulfuric solution. Weight loss, surface studies, atomic absorption spectroscopy, potentiodynamic polarization (PP), impedance spectroscopy (EIS), - more especially, scanning electron microscopy combined with energy dispersive spectroscopy SEM/EDS—and simulation studies were among the methods used to evaluate the efficacy of corrosion inhibition. With 1000 ppm of the inhibitor at 303 K, the weight loss trials had the highest inhibition effectiveness of 96.8 % which obeyed Langmuir adsorption isotherm. The inhibitor QT is represented as mixed-type as per polarization studies. Scanning electron microscopy test results showed the lesser degradation of the lower M-S surface in 0.5 M H₂SO₄ solution at 1000 ppm QT. Moreover, modelling studies employing density functional theory (DFT) and molecular dynamics (MD) showed that the green inhibitor QT adsorbed on the M-S surface and formed a barrier on the metal surface.

We have synthesized indole-based sulfonamides derivatives (1–10), characterized through NMR and HR-EIMS, and screened against α-glucosidase and α-amylase enzymes. All the synthesized analogues showed various degrees of inhibitory potential ranging between 1.10 ± 0.10 to 10.90 ± 0.20 µM (against α-glucosidase) and 0.70 ± 0.10 to 11.30 ± 0.20 µM (against α-amylase) as compared to standard acarbose (IC₅₀ = 38.45 ± 0.10 µM and 1.70 ± 0.10 μM, respectively). In both cases, analogues 5 (IC₅₀ = 1.10 ± 0.10 and 0.40 ± 0.10 μM) and 8 (IC₅₀ = 1.20 ± 0.10 and 0.70 ± 0.10 μM) were identified as the most potent among the series. A structure-activity relationship has been established, which mainly depends upon the substitution pattern around the phenyl ring. The interaction of the most potent analogs with the active site of enzymes was determined through a molecular docking study.

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.