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Characterization, Antibacterial Evaluation and computational study of Synthesized 4,5-bis(Hydroxymethyl)-2-Methylpyridin-3-ol Tetraphenylborate Ion-Pair Complex

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CHEMISTRYOPEN 2025年第3期14卷 e202400422页

作者： Bakheit, Ahmed H. Al-Agamy, Mohamed H. Al-Salahi, Rashad Ali, Essam Alrabiah, Haitham Mostafa, Gamal A. E. King Saud Univ Coll Pharm Dept Pharmaceut Chem POB 2457 Riyadh 11451 Saudi Arabia King Saud Univ Coll Pharm Dept Pharmaceut POB 2457 Riyadh 11451 Saudi Arabia

The synthesis of 4,5-bis(hydroxymethyl)-2-methylpyridin-3-ol tetraphenylborate complex in water using an anion exchange process yielded more than 76 %. The resulting white complex was obtained and characterized using various spectroscopic and analytical techniques, including ultraviolet, infrared radiation (IR), mass, elemental analysis, and nuclear magnetic resonance (NMR). The antimicrobial activity of the formed ion-associate complex was evaluated. The structural, electrical, and bonding properties of a novel pyridoxine-tetraphenylborate ion-pair complex was explored using B3LYP/6-311G(d,p) DFT simulations. Geometries designed for negative complexation energy showed thermodynamically beneficial complex formation. Reduced density gradient (RDG) analysis and non-covalent interaction (NCI) plots showed that van der Waals forces are essential to complex stability. Quantum Theory of Atoms in Molecules (QTAIM) study detected weak and moderate hydrogen bonds in the complex using bond critical point (BCP) features. These results reveal how molecules form and stabilize the pyridoxine-tetraphenylborate ion-pair complex. To know the interaction between receptors and bioactive chemicals, one must understand the mechanism of the ionic complexes formed between bioactive chemicals and/or organic molecules.

关键词： Pyridoxine Ion-pair complex Characterization Antibacterial activity computational study Quantum Theory of Atoms in Molecules (QTAIM) Reduced density gradient (RDG) analysis Non-covalent interaction (NCI)

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Impacts of sac centreline length on hemodynamic of Anterior Cerebral Artery for rupture risk analysis via computational study

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INTERNATIONAL JOURNAL OF MODERN PHYSICS C 2025年第4期36卷

作者： Basem, Ali Jasim, Dheyaa J. Al Bahadli, Yusra A. Mausam, Kuwar Abdulameer, Maha Khalid Almasoudie, Najah Kadum Alian Al-Hussainy, Ali Fawzi Mansoor, Aseel Salah Bahair, Hala Idan, Ameer Hassan Warith Al Anbiyaa Univ Fac Engn Karbala Iraq Al Amarah Univ Coll Dept Petr Engn Maysan Iraq Univ Kerbala Coll Engn Karbala Iraq GLA Univ Inst Engn & Technol Dept Mech Engn Mathura Uttar Pradesh India Al Noor Univ Coll Dept Radiol & Sonar Tech Nineveh Iraq Natl Univ Sci & Technol Coll Pharm Dhi Qar Iraq Ahl Al Bayt Univ Coll Pharm Kerbala Iraq Gilgamesh Ahliya Univ Med Tech Coll Baghdad Iraq Al Farahidi Univ Med Tech Coll Baghdad Iraq Al Zahrawi Univ Coll Dept Pharm Karbala Iraq

Intracranial aneurysms (IAs) are focal dilations of the cerebral arteries that pose a significant risk of rupture, leading to potentially devastating consequences such as subarachnoid hemorrhage. Understanding the hemodynamic factors that contribute to IA rupture risk is critical for improving clinical management and patient outcomes. One important factor that has been studied is the impact of sac centreline length on the hemodynamics of the Anterior Cerebral Artery (ACA), a common location for IAs. This computational study aimed to investigate the relationship between sac centreline length and the hemodynamic parameters of the ACA that are associated with rupture risk. Using patient-specific 3D geometries of the ACA and computational fluid dynamics (CFD) simulations, the researchers analyzed the impact of varying sac centreline lengths on parameters such as wall shear stress, pressure and flow patterns within the aneurysm sac and the parent artery. The results of the computational study disclose that the wall shear stress on the wall of an ACA saccular aneurysm is meaningfully high when the size of the sac centerline length is low. However, the mean oscillatory index change in different sac centerline lengths indicates that the growth of sac centerline length increases blood oscillatory in sac section in ACA cases.

关键词： Hemodynamic computational study saccular aneurysms ACA sac centerline length

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Metal-organic frameworks as cathode electrocatalysts for Li-O2 batteries: A computational study of NiBTC and CuBTC by molecular dynamic simulation

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CHEMICAL PHYSICS LETTERS 2025年 862卷

作者： Sadeghi, Ali Ghaffarinejad, Ali Alemnezhad, Mohammad Mahdi Iran Univ Sci & Technol Fac Chem Res Lab Real Samples Anal Tehran *** Iran Iran Univ Sci & Technol Electroanalyt Chem Res Ctr Tehran *** Iran

This study investigates metal-organic frameworks (MOFs) as cathode electrocatalysts for lithium-oxygen batteries, comparing NiBTC and CuBTC. Using molecular dynamics simulations and geometry optimization, the structural and electrochemical behaviors were examined. The oxygen reduction reaction (ORR) mechanisms identified the rate-determining steps: LiO2 formation for CuBTC and initial lithiation for NiBTC. Interaction energy calculations showed NiBTC's superior adsorption and stability for LiO2 and Li2O2 intermediates. Gibbs free energy changes demonstrated higher ORR feasibility on NiBTC, indicating its potential as a more efficient cathode electrocatalyst. This analysis provides insights into optimizing MOF-based cathodes for advanced energy storage applications.

关键词： Lithium-oxygen batteries Metal-organic framework Molecular dynamic Simulation computational study

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Enhanced antimicrobial activity of microbial cellulose hydrogel crosslinked by citric acid: An experimental and computational study

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Journal of Molecular Liquids 2025年 424卷

作者： Ahmadi, Shabnam Pourebrahimi, Sina Rezaee, Abbas Department of Environmental Health Engineering Faculty of Medical Sciences Tarbiat Modares University Tehran Iraq Department of Chemical and Materials Engineering Concordia University 7141 Sherbrooke Street West MontréalQCH4B 1R6 Canada

In the present study, a carboxymethyl cellulose hydrogel (CMCH) based on microbial cellulose was synthesized through crosslinking cellulose with citric acid (CA) to improve the antimicrobial activity. Besides, its antimicrobial effectiveness against Escherichia coli (E. coli) was evaluated using the disk diffusion assay (DDA), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC). The obtained experimental results suggested that the CMCH had promising antimicrobial activity with the initial CMCH concentration of 1.25 g during 60 min. The density-functional theory (DFT) calculations confirmed that CA formed strong interactions with the hydrogel matrix, resulting in a stable, long-lasting crosslinking network. Meanwhile, the quantum chemical descriptors computed revealed that the CMCH had higher chemical reactivity as compared to carboxymethyl cellulose (CMC). The findings underscore the impact of CA on enhancing the antimicrobial activity of the CMCH, extending its function beyond the conventional role as a typical crosslinking agent for constructing a hydrogel network. © 2025 Elsevier B.V.

关键词： Antimicrobial activity Carboxymethyl cellulose computational study Hydrogel Microbial cellulose

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computational Simulation study-Based Formulation Development and Characterization of MethylprednisoloneLoaded Nanoparticles Containing Chitosan and Pectin to Treat Nocturnal Asthma

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POLYMERS 2025年第1期17卷 24-24页

作者： Voleti, Vijaya Kumar Yusuff, Ismail Abdulkadhar, Mohamed Jalaludeen Al-Sadoon, Mohammad Khalid BS Abdur Rahman Crescent Inst Sci & Technol Crescent Sch Pharm GST Rd Chennai 600048 Tamil Nadu India BS Abdur Rahman Crescent Inst Sci & Technol Crescent Global Outreach Mission Res & Dev GST Rd Chennai 600048 Tamil Nadu India King Saud Univ Dept Zool Coll Sci POB 62521 Riyadh 11451 Saudi Arabia

Nocturnal asthma (NA) is a high-prevalence disease that causes severe respiratory issues, leading to death from early midnight to early morning. In this research, nanoparticulate drug delivery system of methylprednisolone (MP) was developed using chitosan (CH) and pectin (PEC). MP is a synthetic corticosteroid medication widely used for its potent anti-inflammatory activity. computational simulation study (AI-based blend analysis algorithm) was used to identify a better-mixing polymer with MP. MP nanoparticles were formulated by the ionic gelation method with the combination of CH and PEC. To modify the drug release properties, the formed beads were coated with chitosan succinate (CSSC). The morphological characteristics of the beads were determined by SEM analysis. The X-ray radiographic imaging study was used to observe the intactness of MP beads. Histopathological studies were also carried out to find out the toxicity of the beads in the organs of rats. Pectin and chitosan polymers were selected based on the computational simulation study. SEM analysis revealed that the beads had a spherical shape with a rough outer surface. CSSC-coated beads achieved sustained drug release for up to 24 h. X-ray imaging demonstrated the stability of the beads in acidic pH conditions. In vivo pharmacokinetic studies showed that CSSC-coated beads were more stable in the gastrointestinal tract (GIT) than PEC-CH beads and the pure drug. Histological evaluation confirmed that the beads are nontoxic and safe for use in rats. Based on the findings, it was concluded that CSSC-coated beads of MP exhibited superior release properties, making them suitable for a chronomodulated drug delivery system.

关键词： nocturnal asthma computational study methylprednisolone chitosan chitosan succinate chronomodulated delivery system histopathological study

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computational study of the hydrolysis of carbonyl sulphide: Thermodynamics and kinetic constants estimation using ab initio calculations

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JOURNAL OF CHEMICAL THERMODYNAMICS 2017年 110卷 154-161页

作者： Vidal-Vidal, A. Perez-Rodriguez, M. Pineiro, M. M. Univ Vigo Dept Fis Aplicada Vigo Spain

Carbonyl sulphide is the predominant sulphur compound in the atmosphere, contributing to the formation of aerosol particles affecting global climate. Human activity has significantly increased its total amount since the beginning of the Industrial Revolution due to its presence in petroleum and coal, reason why it is necessary to understand and control its emissions. On the other hand, carbonyl sulphide is an undesired substance for catalysis in important industrial processes. Hydrolysis is the most promising among the different strategies to reduce its presence, giving as products carbon dioxide and hydrogen sulphide. In the present work, the mechanism of reaction of carbonyl sulphide hydrolysis process in gas phase was studied from 400 K to 1500 K, equilibrium constants were obtained and reaction yields were estimated, by means of composite quantum-computational methods. Good agreement with literature experimental results confirms the suitability of the chosen methods, specially CBS-QB3, in supporting the reaction mechanism, giving accurate equilibrium constant values, and obtaining realistic yields. The effect of isotopic substitution in OCS was also studied, from 300 K to 1500 K, being much less significant than temperature dependence. (C) 2017 Elsevier Ltd.

关键词： Hydrolysis Carbonyl sulphide Composite methods DFT computational study

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computational study of a latent heat thermal energy storage system enhanced by highly conductive metal foams and heat pipes

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JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY 2020年第5期141卷 1741-1751页

作者： Tiari, Saeed Mahdavi, Mahboobe Gannon Univ Biomed Ind & Syst Engn Dept Erie PA 16541 USA Gannon Univ Dept Mech Engn Erie PA USA

Numerical simulations are performed to analyze the thermal characteristics of a latent heat thermal energy storage system with phase change material embedded in highly conductive porous media. A network of finned heat pipes is also employed to enhance the heat transfer within the system. ANSYS-FLUENT 19.0 is used to create a transient multiphase computational model to simulate the thermal behavior of the storage unit. Copper foam is the porous medium used to enhance the heat transfer and is impregnated with the phase change material, potassium nitrate (KNO3). The effects of the porosity of the metal foam and the quantity of heat pipes on the thermal characteristics of storage unit have been investigated. The results indicated that increasing the quantity of the embedded heat pipes leads to drastic acceleration of both charging and discharging process. Impregnating the copper foam with potassium nitrate phase change material significantly affects the total charging and discharging times of the storage unit. It was shown that the porosity of the metal foam plays a key role in the thermal behavior of the system during the charging and discharging processes.

关键词： computational study Thermal energy storage Melting Solidification Porous media Heat pipe

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computational study on planar dominating set problem

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THEORETICAL COMPUTER SCIENCE 2009年第52期410卷 5455-5466页

作者： Marzban, Marjan Gu, Qian-Ping Jia, Xiaohua Simon Fraser Univ Sch Comp Sci Burnaby BC V5A 1S6 Canada City Univ Hong Kong Dept Comp Sci Hong Kong Hong Kong Peoples R China

Recently, there has been significant theoretical progress towards fixed-parameter algorithms for the DOMINATING SET problem of planar graphs. It is known that the problem on a planar graph with n vertices and dominating number k can be solved in 0(2(0(root k))n) time using tree/branch-decomposition based algorithms. In this paper, we report computational results of Fomin and Thilikos algorithm which uses the branch-decomposition based approach. The computational results show that the algorithm can solve the DOMINATING SET problem of large planar graphs in a practical time and memory space for the class of graphs with small branch width. For the class of graphs with large branch width, the size of instances that can be solved by the algorithm in practice is limited to about one thousand edges due to a memory space bottleneck. The practical performances of the algorithm coincide with the theoretical analysis of the algorithm. The results of this paper suggest that the branch-decomposition based algorithms can be practical for some applications on planar graphs. (C) 2009 Elsevier B.V. All rights reserved.

关键词： PLANAR DOMINATING SET Branch-decomposition Fixed-parameter algorithms Data reduction computational study

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computational study of transverse Peltier coolers for low temperature applications

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INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER 2013年第1期62卷 373-381页

作者： Ali, Syed Ashraf Mazumder, Sandip Ohio State Univ Dept Mech & Aerosp Engn Columbus OH 43210 USA

Transverse thermoelectric effect can be produced artificially by stacking at an angle layers of a thermoelectric material with another material that may or may not be a thermoelectric material. In this exploratory computational study, a new meta-material, comprised of tilted alternating layers of an n-type thermoelectric alloy and a metal, is investigated to gain an understanding of how much cooling can be produced by transverse thermoelectric effect and the conditions under which maximum cooling is attainable. The governing conservation equations of energy and electric current, with the inclusion of thermoelectric effects, are solved on an unstructured mesh using the finite-volume method to simulate a transverse Peltier cooler under various operating conditions. First, the code is validated against experimental data for a n-Bi2Te3-Pb meta-material, and subsequently explored. It is found that intermediate applied currents produce maximum temperature depression (Delta T). Optimum values of the geometric design parameters such as tilt angle and device aspect ratio are also established through parametric studies. Finally, it is shown that the Delta T can be amplified by constricting the phonon (heat) transport cross-section while keeping the electron (current) transport cross-section unchanged a strategy that cannot be employed in conventional thermoelectric devices where electrons and phonons follow the same path. This makes transverse Peltier coolers particularly attractive for generating large Delta T without multi-stage cascading. (C) 2013 Elsevier Ltd. All rights reserved.

关键词： Thermoelectric Peltier cooler Transverse device computational study Low temperature Bismuth telluride

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computational study of water transport in proton exchange membrane fuel cells

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JOURNAL OF POWER SOURCES 2006年第2期156卷 211-223页

作者： Um, Sukkee Wang, Chao-Yang Korea Inst Energy Res Fuel Cell Res Ctr Taejon 305600 South Korea Penn State Univ University Pk PA 16802 USA

A computational fuel cell dynamics framework is used to develop a unified water transport equation for a proton exchange membrane fuel cell (PEMFC). Various modes of water transport, i.e., diffusion, convection and electro-osmotic drag, are incorporated in the unified water transport equation. The water transport model is then applied to elucidate water management in three-dimensional fuel cells with dry-to-low humidified inlet gases after its validation against available experimental data for dry oxidant and fuel streams. An internal circulation of water with the aid of counter-flow design is found to be of vital importance for low-humidity operation, for example, in the portable application of a PEMFC without an external humidifier. The general features of water transport in PEMFCs are discussed to show various water transport regimes of practical interest, such as anode water loss, cathode flooding, and the equilibrium condition of water at the channel outlets, particularly for limiting situations where anode and cathode water profiles acquire an equilibrium state. From the practical point of view, the effects of the flow arrangement, membrane thickness, and inlet gas humidity as important determinants of fuel cell performance are also analyzed to elucidate fuel cell water transport characteristics. (c) 2005 Elsevier B.V. All rights reserved.

关键词： proton exchange membrane fuel cell computational study water transport

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