Yazar "Darroudi, Mahdieh" seçeneğine göre listele

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    Anti-corrosion behavior of 2-(((4-((2-morpholinoethyl)(pyridin-2-ylmethyl)amino)butyl)imino)methyl)naphthalen-1-ol on mild steel in hydrochloric acid solution: Experimental and theoretical studies
    (Elsevier Science Sa, 2022) Bozorg, Mansoor; Rezaeivala, Majid; Borghei, Sina; Darroudi, Mahdieh
    A naphthalene derivative, namely 2-(((4-((2-morpholinoethyl)(pyridin-2-ylmethyl)amino) butyl) imino)methyl) naphthalen-1-ol (HL) was synthesized and its chemical structure characterized by spectroscopic techniques (H-1, C-13 Nuclear magnetic resonance, Fourier-transform infrared spectroscopy and Mass spectroscopy). Its action as a corrosion inhibitor against the corrosion of mild steel in 1.0 M HCl solution was fully investigated at ambient temperature using weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. The results indicated inhibition efficiency for HL at 100 ppm concentration of greater than 90%. It was determined that the adsorption of HL molecules on the metallic surfaces occurred through the heteroatoms, based on a combination of physical and chemical mechanisms (calculated value of Delta G(ads)(0) was -23.1 kJ/mol) and followed a Langmuir adsorption process leading to a reduction in electric double layer capacitance (20.40 mu F.cm(-2) at 100 ppm concentration). The highest occupied molecular orbital and lowest unoccupied molecular orbital calculations demonstrated that the existence of nitrogen and oxygen atoms in the morpholine and pyridine groups of the protonated form of the molecule assisted in the formation of stronger bonds with the surface of the metal, as an electrophilic agent.
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    Efficient N-sulfopropylation of chitosan with 1,3-propane sultone in aqueous solutions: neutral pH as the key condition
    (Royal Soc Chemistry, 2021) Heydari, Abolfazl; Darroudi, Mahdieh; Lacik, Igor
    Conjugation of strong anionic sulfonate groups to chitosan (CS) is typically used for converting the weak cationic CS to its polyampholyte derivatives, which are of interest to different areas benefiting from both cationic and anionic groups. The content of anionic charges can be tuned by varying the level of sulfonation, which is a fundamental characteristic expressed as the degree of substitution (DS). The subject of this work is the synthesis of the representative polyampholyte of this class, N-(3-sulfopropyl)chitosan salt (SPCS), by the reaction of CS with 1,3-propane sultone (PrS) in water. According to the literature, this reaction is mostly performed under acidic conditions and should lead to SPCS with high DS values. We found that such DS values are likely overestimated due to the presence of a non-covalently bonded sulfopropyl group, originating from extensive PrS hydrolysis, in the SPCS structure. In this work, the combination of experimental and theoretical approaches resulted in selecting a neutral pH for the SPCS synthesis, which increased the efficiency of the N-sulfopropylation reaction. Quantum chemistry calculations suggest that this finding primarily corresponds with the higher reactivity of PrS to a non-protonated glucosamine unit compared to a protonated one, where the molar fraction of the non-protonated unit at neutral pH is remarkably higher than that at acidic pH. The developed purification conditions make the SPCS free from the non-covalently bonded sulfopropyl groups. We show that true DS values can be obtained by NMR regardless of the level of SPCS purity, and also by elemental analysis for completely pure SPCS. It is noticeable that while the true DS values for SPCS synthesized under acidic conditions are limited to only around 5%, these values range between 25 and 95% for SPCS synthesized under neutral conditions and can be readily controlled by the weight ratio between CS and PrS. Hence, this work provides guidelines for a simple yet feasible and highly effective sulfopropylation reaction with PrS under aqueous conditions.
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    Silica mesoporous structures: effective nanocarriers in drug delivery and nanocatalysts
    (Mdpi, 2020) Mirzaei, Masoud; Zarch, Malihe Babaei; Darroudi, Mahdieh; Sayyadi, Khalilollah; Keshavarz, Seyed Tahmoures; Sayyadi, Jalil; Maleki, Hajar
    The application of silica mesoporous structures in drug delivery and the removal of pollutants and organic compounds through catalytic reactions is increasing due to their unique characteristics, including high loading capacities, tunable pores, large surface areas, sustainability, and so on. This review focuses on very well-studied class of different construction mesoporous silica nano(particles), such as MCM-41, SBA-15, and SBA-16. We discuss the essential parameters involved in the synthesis of these materials with providing a diverse set of examples. In addition, the recent advances in silica mesoporous structures for drug delivery and catalytic applications are presented to fill the existing gap in the literature with providing some promising examples on this topic for the scientists in both industry and academia active in the field. Regarding the catalytic applications, mesoporous silica particles have shown some promises to remove the organic pollutants and to synthesize final products with high yields due to the ease with which their surfaces can be modified with various ligands to create appropriate interactions with target molecules. In the drug delivery process, as nanocarriers, they have also shown very good performance thanks to the easy surface functionalization but also adjustability of their porosities to providing in-vivo and in-vitro cargo delivery at the target site with appropriate rate.
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    Tb-2(WO4)(3)@N-GQDs-FA as an efficient nanocatalyst for the efficient synthesis of beta-aminoalcohols in aqueous solution
    (Elsevier, 2021) Azizi, Sajjad; Darroudi, Mahdieh; Soleymani, Jafar; Shadjou, Nasrin
    In the current study, Tb-2(WO4)(3)@N-(GQDs) modified with folic acid (FA) was synthesized during the chemical reaction of terbium(III) tungstate nanoparticles with nitrogen doped graphene quantum dots (N-GQDs) and introduced as a heterogeneous catalyst for the synthesis of beta-aminoalcohols derivatives. The as-prepared Tb-2 (WO4)(3)@N-GQDs-FA is stable at -4 degrees C for at least two month. Herein, the reaction time, solvent, and catalyst amount were optimized. The Tb nanostructure exhibited a high efficiency, less reaction time, excellent selectivity, and simple procedure for these transformations. The performance Tb-2(WO4)(3)@N-GQDs-FA nanocatalyst catalyst is thoroughly investigated which shows several advantageous including to facile preparation from readily available materials. Shorter reaction times, easy work-up, green reaction media, higher yields (near 97%), and no need to use the chromatographic column are the advantages of the reported synthetic method. The Tb-2(WO4)(3)@N-GQDs-FA heterogeneous catalyst has been recovered through filtration and also reused for multiple cycles. The recovered catalyst can be used for another nine successive reaction without noticeable loss in activity. The reaction time is also reduced and products can be obtained by convenient workup, and environmental-friendly procedure.