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1.
Antibodies (Basel) ; 13(2)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38804306

RESUMO

Considering the COVID-19 pandemic, this research aims to investigate some herbs as probable therapies for this disease. Achillea millefolium (Yarrow), Alkanet, Rumex patientia (Patience dock), Dill, Tarragon, and sweet fennel, including some principal chemical compounds of achillin, alkannin, cuminaldehyde, dillapiole, estragole, and fenchone have been selected. The possible roles of these medicinal plants in COVID-19 treatment have been investigated through quantum sensing methods. The formation of hydrogen bonding between the principal substances selected in anti-COVID natural drugs and Tyr-Met-His (the database amino acids fragment), as the active area of the COVID protein, has been evaluated. The physical and chemical attributes of nuclear magnetic resonance, vibrational frequency, the highest occupied molecular orbital energy and the lowest unoccupied molecular orbital energy, partial charges, and spin density have been investigated using the DFT/TD-DFT method and 6-311+G (2d,p) basis set by the Gaussian 16 revision C.01 program toward the industry of drug design. This research has exhibited that there is relative agreement among the results that these medicinal plants could be efficient against COVID-19 symptoms.

2.
J Mol Model ; 29(6): 170, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37148380

RESUMO

CONTEXT: Langmuir adsorption of gas molecules of NO, NO2, and NH3 on the graphitic GaN and GaP sheets has been accomplished using density functional theory. The changes of charge density have shown a more important charge transfer for GaN compared to GaP which acts both as the electron donor while gas molecules act as the stronger electron acceptors through adsorption on the graphitic-like GaN surface. The adsorption of NO and NO2 molecules introduced spin polarization in the PL-GaN sheet, indicating that it can be employed as a magnetic gas sensor for NO and NO2 sensing. METHODS: The partial electron density states based on "PDOS" graphs have explained that the NO and NO2 states in both of GaN and GaP nanosheets, respectively, have more of the conduction band between - 5 and - 10 eV, while expanded contribution of phosphorus states is close to gallium states, but nitrogen and oxygen states have minor contributions. GaN and GaP nanosheets represent having enough capability for adsorbing gases of NO, NO2, and NH3 through charge transfer from nitrogen atom and oxygen atom to the gallium element owing to intra-atomic and interatomic interactions. Ga sites in GaN and GaP nanosheets have higher interaction energy from Van der Waals' forces with gas molecules.

3.
J Mol Model ; 29(4): 119, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36988725

RESUMO

CONTEXT: In this research, CO2 and NO2 adsorption on doped nanographene (NG) sheets with transition metals (Fe, Ni, Zn) and (Mn, Co, Cu), respectively, have been applied for scavenging of these toxic gases as the environmental pollutants. The values of changes of atomic charge density have illustrated a more significant charge transfer for Ni-doped C-NG through CO2 adsorption and a more remarkable charge transfer for Co-doped C-NG through NO2 adsorption. The data of NMR spectroscopy has depicted several fluctuations around the graph of Zn-doped on the nanographene surface. The thermodynamic results from IR spectroscopy have indicated that [Formula: see text] values are almost similar for doped metal transitions of Mn, Co, and Cu on the C-NG nanosheet, while [Formula: see text] has the largest gap of Gibbs free energy adsorption with dipole moment. METHODS: The Langmuir adsorption model with a three-layered ONIOM using CAM-B3LYP functional accompanying LANL2DZ, EPR-III and 6-31 + G (d,p) basis sets due to Gaussian 16 revision C.01 program on the complexes of CO2 → (Fe, Ni, Zn) and NO2 → (Mn, Co, Cu) doped on the C-NG has been accomplished. Then, NMR and IR spectroscopy, nuclear quadrupole resonance, and natural bond orbital analysis have been accomplished for evaluating chemical shielding tensors, thermodynamic properties, electric potential, and occupancy fluctuation through bond orbitals, respectively. In addition, frontier orbitals of LUMO, HOMO, and also a series of chemical reactivity parameters have been calculated. Finally, time-dependent-DFT method due to UV-VIS spectrums has been accomplished to discern the low-lying excited states of CO2 and NO2 adsorption on the (Fe, Ni, Zn) and (Mn, Co, Cu), respectively, doped C-NG sheet.

4.
Micromachines (Basel) ; 14(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36837941

RESUMO

Twenty-eight samples of {[(1-x-y) LiCo0.3Cu0.7](Al and Mg doped)]O2}, xLi2MnO3, and yLiCoO2 composites were synthesized using the sol-gel method. Stoichiometric weights of LiNO3, Mn(Ac)2⋅4H2O, Co(Ac)2⋅4H2O, Al(NO3)3.H2o, Mg(NO3)2⋅6H2O, and Cu(NO3)2.H2O for the preparation of these samples were applied. From this work, we confirmed the high performance of two samples, namely, Sample 18, including Al doped with structure "Li1.5Cu0.117Co0.366Al0.017Mn0.5O2" and Sample 17, including Mg doped with structure "Li1.667Cu0.1Mg0.017Co0.217Mn0.667O2", compared with other compositions. Evidently, the used weight of cobalt in these two samples were lower compared with LiCoO2, resulting in advantages in the viewpoint of cost and toxicity problems. Charge and discharge characteristics of the mentioned cathode materials were investigated by performing cycle tests in the range of 2.2-4.5 V. These types of systems can help to reduce the disadvantages of cobalt arising from its high cost and toxic properties. Our results confirmed that the performance of such systems is similar to that of pure LiCoO2 cathode material, or greater in some cases. The biggest disadvantages of LiCoO2 are its cost and toxic properties, typically making it cost around five times more to manufacture than when using copper.

5.
J Mol Model ; 28(1): 11, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34928451

RESUMO

The interaction between drugs and single-walled carbon nanotubes is proving to be of fundamental interest for drug system of delivery and nano-bio-sensing. In this study, the interaction of pristine CNT with carbazochrome, an anti-hemorrhagic or hemostatic agent, was investigated with M06-2X functional and 6-31G* basis set. All probable positions of related adsorption for these kind drugs were thought-out to find out which one is energetically suitable. Based on the achieved data, the stronger interactions appeared the oxygen atom of C = O group and nitrogen atom of imine groups. The topology analysis of QTAIM (quantum theory of atoms in a molecule) method was accomplished to understand the properties of interactions between the CNT and carbazochrome. Frontier molecular orbital energies of all systems, global index including stiffness, softness, chemical Gibbs energies, and electrophilicity parameters, as well as some other important physical data such as dipole moment, polarizability, anisotropy polarisibility, and hyperpolaribility were calculated, evaluated, and then compared together. The essence of the formed bonding model progress along the reaction roots was further validated using electron localization function (ELF) calculations. The highest values of adsorption energies were determined in the range of 18.24 up to 22.12 kcal mol-1 for these kind systems. The acceptable recovery time of 849 s was obtained for the desorption of carbazochrome from the CNT surface under UV-light. The final results exhibit that carbazochrome can serve as a promising carrier and also as sensitive sensors in any kind of practical application.


Assuntos
Adrenocromo/análogos & derivados , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Hemostáticos/química , Modelos Moleculares , Nanotubos de Carbono/química , Adrenocromo/administração & dosagem , Adrenocromo/química , Algoritmos , Teoria da Densidade Funcional , Hemostáticos/administração & dosagem , Teoria Quântica
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