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1.
Environ Sci Pollut Res Int ; 31(24): 34881-34895, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38714613

RESUMO

The structural, mechanical, vibrational, electronic, optical, SLME, thermoelectric, and thermodynamic properties of X2GaAgCl6 (X = Cs, Rb), a double perovskite material, were computed by employing Density Functional Theory (DFT). CASTEP and Quantum ESPRESSO were used to perform first-principles calculations. X2GaAgCl6 possesses a cubic structure with the space-group symmetry Fm-3 m. The lattice parameters of Cs2GaAgCl6 and Rb2GaAgCl6 were optimized using the energy-volume curves, resulting in values of 7.357 Å and 7.365 Å, respectively. The population analysis confirmed the charge transfer among transition metals and halogen atoms. The stability of crystal X2GaAgCl6 (X = Cs, Rb) is effectively demonstrated by analyzing phonon dispersion curves with no negative frequencies. The band structure calculations indicated the semiconducting nature of compounds with energy gaps of 0.96 eV and 0.88 eV for Cs2GaAgCl6 and Rb2GaAgCl6, respectively. The optical characteristics results confirm that the examined materials are suitable for devices working, primarily in the electromagnetic spectrum's visible region. SLME results showed that Cs2GaAgCl6 has 30% and Rb2GaAgCl6 has 27% efficiency, respectively, suggesting their use in photovoltaics. The thermoelectric properties of X2GaAgCl6 (X = Cs, Rb) were calculated by using the BoltzTraP code in the temperature range of 300 to 800 K. The quasi-harmonic Debye model was applied to calculate the thermodynamic characteristics.


Assuntos
Compostos de Cálcio , Energia Solar , Termodinâmica , Titânio , Titânio/química , Compostos de Cálcio/química , Óxidos/química
2.
Mol Biotechnol ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456961

RESUMO

The molecular electron density theory (MEDT) was employed to examine the [4 + 2] cycloaddition reaction between (E)-N-((dimethylamino)methylene)benzothioamide (1) and (S)-3-acryloyl-4-phenyloxazolidin-2-one (2) at the B3LYP/6-311++G(d,p) design level. Parr functions and energy studies clearly show that this reaction is regio- and stereoselective, in perfect agreement with experimental results. By evaluating the chemical mechanism in terms of bond evolution theory (BET) and electron localization function (ELF), which divulges a variety of variations in the electron density along the reaction path, a single-step mechanism with highly asynchronous transition states structures was revealed. Additionally, we conducted a docking study on compounds P1, P2, P3, and P4 in the SARS-CoV-2 main protease (6LU7) in comparison to Nirmatrelvir. Our findings provide confirmation that product P4 may serve as a potent antiviral drug.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38052731

RESUMO

In this study, we explored aluminum corrosion inhibition field of study in a 1 M HCl solution, harnessing the power of essential oils extracted from rosemary and eucalyptus plants. Our exploration gives a comprehensive analysis of the pivotal factors that shape the corrosion inhibition process. Our scientific journey was marked by a deliberate and systematic approach, encompassing the utilization of gravimetric analysis (weight loss), electrochemical potentiodynamic polarization, and the sophisticated electrochemical impedance spectrometry (EIS) techniques. Our findings unveiled promising and nuanced outcomes, particularly in the area of the electrochemical technique. This method demonstrated remarkable inhibition efficiencies, ranging from 42% to an impressive 92% for rosemary essential oil and from 37 to 84% for eucalyptus essential oil. These results unveiled a dynamic relationship between essential oil concentration and inhibition efficiency, a revelation that further deepens our understanding of the corrosion inhibition process. The inhibition efficiency increased with higher concentrations of essential oil but decreased with elevated temperatures. Furthermore, our analysis traversed into the realms of potentiodynamic and thermodynamic insights. These analytical techniques unearthed the complex mechanisms at play, explaining the pathway followed by the studied inhibitors. They exhibited their prowess by forming protective films on the metal surface, acting as vigilant protectors against the relentless forces of corrosion. Complementing our experimental findings, our study of computational chemistry through density functional theory (DFT) unveiled remarkable insights. It elucidated the spontaneous adsorption process of inhibitor molecules onto the aluminum surface in the presence of H2O solvent. This computational harmony with our experimental results strengthened our confidence in the robustness of our findings. One of the key findings of this study was the superior inhibitory power of camphor in rosemary EO and ß-myrcene in eucalyptus essential oil EO, respectively, attributed to the distinctive characteristics of the active sites found in each compound. The inhibitory effectiveness followed the order ß-myrcene > camphor > borneol > α-pinene > bornyl acetate > p-cymene > 1,8-cineole. These compounds, notable for their distinct active sites, emerged as exceptional agents in the pursuit of effective corrosion inhibition.

5.
J Fluoresc ; 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37668770

RESUMO

Employing the Molecular Electron Density Theory, [3 + 2] cycloaddition processes between 4-chlorobenzenenitrileoxide and linalool, have been applied using the DFT/B3LYP/6-311(d,p) method, activation, reaction energies and the reactivity indices are calculated. In an investigation of conceptual DFT indices, LIL-1 will contribute to this reaction as a nucleophile, whilst NOX-2 will participate as an electrophile. This cyclization is regio, chemo and stereospecific, as demonstrated by the reaction and activation energies, in clear agreement with the experiment's results, in addition, ELF analysis revealed that the mechanism for this cycloaddition occurs in two steps. Furthermore, a docking study was conducted on the products studied, and the interaction with the protein protease COVID-19 (PDB ID: 6LU7), our results indicate that the presence of the -OH group increases the affinity of these products, moreover, adsorption study by chromatography was made on silica gel as support; our outcome reveals that the -OH group creates an intramolecular hydrogen bond in the product P2, while in the product P3 will create a hydrogen bond with the silica gel which makes the two products P2 and P3 are very easy to separate by chromatography, this result is in excellent agreement with the Rf retention value. The study might provide a fundamental for developing natural anti-viral compound in promoting human health.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37405604

RESUMO

The efficacy of 34 pyrazoline derivatives as carbonic anhydrase inhibitors was studied in silico. The quantum descriptors were calculated by the DFT/B3LYP method using the 6-31G(d) basis; the dataset was randomly divided into training and testing. By altering the compounds in the sets, four models were created, and they were then used to determine the predicted pIC50 values for the six chemicals in the test set. According to the OECD guidelines for QSAR model validation and the Golbraikh and Tropsha's criteria for model approval, each created model was independently validated both internally and externally, along with YRandomization. Model 3 is chosen because it has higher R2, R2test, and Q2cv values (R2 = 0.79, R2test = 0.95, Q2cv = 0.64). Only one descriptor has a proportional influence on pIC50 activity, but the other four descriptors have an inverse influence on pIC50 because of the negative contribution coefficient. Given the descriptors of the model, we could propose new molecules with remarkable inhibitory activity.

7.
Artigo em Inglês | MEDLINE | ID: mdl-37198364

RESUMO

Today, hydrogen is one of the most credible options for a non-polluting, carbon-free energy carrier. Hydrogen can be obtained or produced by different means from different renewable energy sources and can be stored in solid, liquid, or gaseous form. Storing hydrogen in complex hydrides in solid form is one of the most efficient methods of storage because they are secure, offer high hydrogen capacity, and demand optimal functioning conditions. Complex hydrides give a large gravimetric capacity that allows large amounts of hydrogen to be stored. This study examined the effects of triaxial strains on hydrogen storage properties of the perovskite-type compound K2NaAlH6. The analysis was conducted through first principle calculations using the full potential linearized augmented plane wave (FP-LAPW) approach. Our results indicate that the formation energy and desorption temperature of K2NaAlH6 hydride were improved under a maximum triaxial compressive strains of ε ≈ - 5%. Specifically, the values of formation energy and desorption temperature were - 40.14 kJ/mol.H2 and 308.72 K, respectively, compared to the original values of - 62.98 kJ/mol.H2 and 484.52 K. In addition, the analysis of the densities of states showed that changes in the dehydrogenation and structural properties of K2NaAlH6 were closely linked to the Fermi level value of the total densities of states. These findings provide valuable insights into the potential of K2NaAlH6 as a hydrogen storage material.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37195616

RESUMO

1,10-Phenanthroline (PHN) is a nitrogen-containing heterocyclic organic compound that is widely used in a variety of applications, including chemosensors, biological studies, and pharmaceuticals, which promotes its use as an organic inhibitor to reduce corrosion of steel in acidic solution. In this regard, the inhibition ability of PHN was examined for carbon steel (C48) in a 1.0 M HCl environment by performing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), mass loss, and thermometric/kinetic. Additionally, scanning electron microscopy (SEM) was used to examine the surface morphology of C48 immersed in 1.0 M HCl protected with our inhibitor. According to the PDP tests, increasing the PHN concentration resulted in an improvement in corrosion inhibition efficiency. Besides, the maximum corrosion inhibition efficiency is about 90% at 328 K. Furthermore, the PDP assessments demonstrated that PHN functions as a mixed-type inhibitor. The adsorption analysis reveals that our title molecule mechanism is due to physical-chemical adsorption, as predicted by the Frumkin, Temkin, Freundlich, and Langmuir isotherms. The SEM technique exhibited that the corrosion barrier occurs due to the adsorption of the PHN compound through the metal/1.0 M HCl interface. In addition, the computational investigations based on a quantum calculation using density functional theory (DFT), reactivity (QTAIM, ELF, and LOL), and molecular-scale by Monte Carlo (MC) simulations confirmed the experimental results by providing further insight into the mode of adsorption of PHN on the metal surface, thus forming a protective film against corrosion on the C48 surface.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36943564

RESUMO

The objective of this work is to study the adsorption capacity of a natural and low-cost material prepared from argan waste treated with H3PO4 towards two dyes of different molecular charges and presenting an acute toxicity, the methyl orange (MO, anionic dye) and the methylene blue (MB, cationic dye). The prepared adsorbent was characterized by SEM, EDX, FTIR, and BET specific surface. These analyses showed the presence of C (42%), O (55%), and P (3%) and a remarkable difference between the morphology of the precursor and that of the obtained material with a specific surface of 475 m2/g and a very porous structure as well as the main functional groups, O-H, C=O, and C-H. The influence of the pH showed a maximum adsorption at pH =2 for MO and at pH = 10 for MB. Investigation of the effect of time on the adsorption of anionic and cationic dyes revealed that the contact time at equilibrium was 240 and 180 min, respectively. The isotherms that best fit the adsorption of MO and MB are the Langmuir model and the Freundlich model respectively. The kinetic study showed that the experimental data are in agreement with the pseudo-second-order model. Regeneration of the saturated material was also studied for the probability of reusing the adsorbent in many experiments. The valorization of argan waste into activated carbon using H3PO4 has allowed to obtain an effective adsorbent for the removal of anionic and cationic dyes and create an added value for environmental sustainability.

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