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Attar Kubaib N. Nadeem Afroze Predhanekar Mohamed Imran Prabu Natarajan Devipriya Balu Anjum Ansari 《International journal of quantum chemistry》2024,124(3):e27330
The study is focused on examining 2,5-Substituted 4-Pyrone based compounds through quantum chemical and topological analysis techniques, evaluating the properties of these compounds, including their geometrical structure, intermolecular interactions and assess their possible applications. Additionally, the molecular stability, charge delocalization and UV-Visible data was investigated and compared with the calculated energy and oscillator strength using the TD-DFT approach. The researchers observed that charge transfer occurred within the molecule, indicated by the HOMO and LUMO energies. It was also found that the compound exhibited planarity and higher chemical reactivity. The calculated Mulliken charges and molecular electrostatic potential were used to interpret the Fukui index data that help predict reactive sites and understand the reactivity patterns of specific atoms in a compound. The study is aimed to understand the role of NCI in the molecule under investigation using electron localization functions and localized orbit locator methods. Molecular docking and ADMET studies were conducting involving a detailed MD simulation of a protein-ligand complex using the OPLS3e force field and the SPC water model. These findings could prove to be beneficial in developing new therapeutic agents with various pharmacological effects and potential toxicities. 相似文献
33.
An analytical and numerical study of peristaltic transport of a Johnson-Segalman fluid in an endoscope 下载免费PDF全文
In the present study, we discuss the peristaltic flow of a Johnson-Segalman fluid in an endoscope. Perturbation, homotopy, and numerical solutions are found for the non-linear differential equation. The comparative study is also made to check the validity of the solutions. The expressions for pressure rise frictional forces, pressure gradient, and stream lines are presented to interpret the behavior of various physical quantities of the Johnson-Segalman fluid. 相似文献
34.
Sohail Nadeem Mishal Nayab Kiani Anber Saleem Alibek Issakhov 《Electrophoresis》2020,41(13-14):1198-1205
The present paper addresses microvascular blood flow with heat and mass transfer in complex wavy microchannel modulated by electroosmosis. Investigation is carried out with joule heating and chemical reaction effects. Further, viscous dissipation is also considered. Using Debye–Huckel, lubrication theory, and long wavelength approximations, analytical solutions of dimensionless boundary value problems are obtained. The impacts of different parameters are examined for temperature and concentration profile. Furthermore, nature of pressure rise is also investigated to analyze the pumping characteristics. Important results of flow phenomena are explored by means of graphs. 相似文献
35.
This research is made to visualize the boundary layer flow by a curved stretching sheet embedded in porous medium. The geometry is bended(curved), therefore the curvilinear coordinates are used to model the present problem.Fluid is electrically conducting with the presence of uniform magnetic field. The governing non-linear partial differential equation reduces to non-linear ordinary differential equations by using the dimensionless suitable transformations. The numerical solutions are obtained by using the method bvp4c from MATLAB. The effects of curvature parameter, nondimensional magnetic parameter, and porosity parameter on the velocity field and skin friction coefficient are examined.The skin friction profile enhances with enhancing the values of porosity and magnetic parameter. Comparison of the present results with the existing results in the literature for the flat surface is also given. 相似文献
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Sikandar Azam Muhammad Imran Amin Ur Rahman Asif Nadeem Riadh Neffati 《International journal of quantum chemistry》2023,123(3):e27025
The optical properties, electronic charge density, electronic structure of the new layered selenides materials, BaGdCuSe3, CsUCuSe3, CsZrCuSe3, and CsGdZnSe3 compounds have been calculated by using the full potential and linear augmented plane wave (FP-LAPW) methods as applied in the WIEN2k package, which is based on the density functional theory. The ALnMSe3 compound's structure of these was (A = Cs, Ba; Ln = Zr, Gd, U; M = Cu, Zn) is composed of (n = 1, 2) layers, which might be separated by A atoms. It is to be observed that there is strong hybridization between the s, p, and d states of Zr, Gd, and Cu atoms. Around the gadolinium atom, the charge density contours are completely circular, but the Gadolinium “Gd” atom shows an ionic nature. To calculate the refractive index, we used Kramer's Kronig correlations with the imaginary part dielectric function. The decrease in the refractive index is due to the lack of probability for direct excitation of the electrons, resulting in a loss of energy. The value of the static refractive index for all reference compounds is about 1.75–2.25, which is indication that the material used in optoelectronic devices. 相似文献
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A hybrid isothermal model for the homogeneous-heterogeneous reactions in ferrohydrodynamic boundary layer flow is established. The characteristics of Newtonian heating and magnetic dipole in a ferrofluid due to a stretchable surface is analyzed for three chemical species. It is presumed that the isothermal cubic autocatalator kinetic gives the homogeneous reaction and the first order kinetics gives the heterogeneous (surface) reaction. The analysis is carried out for equal diffusion coefficients of all autocatalyst and reactions. Heat flux is examined by incorporating Fourier's law of heat conduction. Characteristics of materialized parameters on the magneto-thermomechanical coupling in the flow of a chemically reactive species are investigated. Further, the heat transfer rate and friction drag are depicted for the ferrohydrodynamic chemically reactive species. It is evident that the Schmidt number has increasing behavior on the rate of heat transfer in the boundary layer. Comparison with available results for specific cases is found an excellent agreement. 相似文献
39.
A. Nadeem M. Nawaz S. U. Haq S. Shahzada M. A. Baig 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,53(2):147-151
We report term energies and quantum defects of highly excited even-parity states of mercury in the 83 876–84 140 cm-1 energy range, employing a two-step laser excitation scheme via the S0↦6s6p3P1 inter-combination transition. Two dye lasers, pumped by a common Nd:YAG laser, were frequency doubled by BBO crystals and
used to record the spectra in conjunction with a thermionic diode ion detector. Our new observations include the much extended
D2 (22 ≤n ≤52) series and a few members of the S1 (24 ≤n ≤30) Rydberg series. Members of the D2 Rydberg series with such a high n value are reported for the first time. The relative intensities of the D2 and S1 transitions (m = 4, 5 and 6) of group II-B elements excited from the P1 inter-combination states are also discussed. 相似文献
40.