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The Effect of Metal Ion Chelation on Formation of Perovskite Versus Perovskite-Related Compounds and The Study of Their Photocatalytic Activity
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In this study, effect of chelate ligands containing carboxylic, phenolic, and amine functional groups on the synthesis of related-perovskite Ca2Fe2O5 versus perovskite CaFeO3 structures have been investigated. Herein, the application of chelating-agent method, e.g. EDTA, Citric Acid, NTA, malonic acid, maleic acid, catechol, acetylaceton, p-tert-butycatechol, aminophenolic derivative ligand, and 2-hydroxyiminodiacetic acid, in comparison to co-precipitation method was also undertaken. The crystalline structure of the obtained perovskites were compared with those of co-participation method in solid state. Experimentally, it was found that the related XRD bands for CaFeO3 were appeared in the...
Development of Biocompatible and Fluorescent Platforms Based on Carbon Dots and Deep Eutectic Solvents for Detection of Some Carcinogenic and Antidepressant Compounds
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The main focus of this thesis was on fluorescence sensors development based on carbon dots and deep eutectic solvents. Accordingly, an attempt was made to synthesize carbon dots and modified with deep eutectic solvents as biocompatible sensors. Eventually, development and application of these sensors in analytical systems ultimately led to satisfactory and comparable results with previous methods. In the first project, a rapid and miniaturized fluorescent probe based on the ultrasound‒assisted formation of carbon dots (CDs) in a metallic deep eutectic solvent (MDES) was developed and conveniently implemented to detect 4-MeI in commercial dark soft drinks. In-situ synthesis of CDs-chelated...
Investigation of Amyloid-Beta Inhibition using Multifunctional Peptide Drugs Associated with Metal Ions
, Ph.D. Dissertation Sharif University of Technology ; Shamloo, Amir (Supervisor)
Abstract
Many experimental and theoretical studies have suggested that zinc binding to Aβ could promote amyloid-β aggregation and reactive oxygen species (ROS) production induced by AD disease. Therefore, the introduction of multifunctional drugs capable of chelating zinc metal ion and inhibiting Aβ aggregation is a promising strategy in the development of AD treatment. In present study molecular docking and molecular dynamics (MD) simulations were used to evaluate the efficacy of two new bifunctional peptide drug, composed of two different domains: C-terminal hydrophobic region of Aβ and Zn2+ chelator region. To evaluate the multifunctionality of the ligands, a comprehensive set of MD simulations up...
Overcome low intrinsic conductivity of Niox through triazinyl modification for highly efficient and stable inverted perovskite solar cells
, Article Solar RRL ; Volume 6, Issue 9 , 2022 ; 2367198X (ISSN) ; Wang, T ; Li, Y ; Pu, X ; Chen, H ; Li, Y ; Yang, B ; Zhang, Y ; Zhao, J ; Cao, Q ; Chen, X ; Ghasemi, S ; Hagfeldt, A ; Li, X ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Nickel oxide (NiOx) is a promising hole transport material in inverted organic-inorganic metal halide perovskite solar cells. However, its low intrinsic conductivity hinders its further improvement in device performance. Here, we employ a trimercapto-s-triazine trisodium salt (TTTS) as a chelating agent of Ni2+ in the NiOx layer to improve its conductivity. Due to the electron-deficient triazine ring, the TTTS complexes with Ni2+ in NiOx via a strong Ni2+-N coordination bond and increases the ratio of Ni3+:Ni2+. The increased Ni3+ concentration adjusts the band structure of NiOx, thus enhancing hole density and mobility, eventually improving the intrinsic conductivity of NiOx. As a result,...
Comparison of oxygen permeation through some perovskite membranes synthesized with EDTNAD
, Article Reaction Kinetics, Mechanisms and Catalysis ; Volume 100, Issue 2 , August , 2010 , Pages 459-469 ; 18785190 (ISSN) ; Nazari, K ; Seyed Matin, N ; Safekordi, A. A ; Ghanbari, B ; Zarrinpashne, S ; Ahmadi, R ; Sharif University of Technology
Abstract
Three dense membranes of types SrCo0.8Fe0.2O 3-δ (SCF(82)), La0.6Sr0.4Co 0.8Fe0.2O3-δ (LSCF(6482)) and La 0.8Sr0.2Co0.6Fe0.4O 3-δ (LSCF(8264)) perovskites were prepared by complexation applying a chelating agent, ethylene diamine N,N,N′,N′-tetra-N- acetyl-diamine (EDTNAD). The oxygen permeation flux through the perovskite membranes was measured as a function of temperature within 1,073-1,223 K as well as the oxygen partial pressure of 0.1-1.0 bar. The oxygen permeation fluxes for the membranes, SCF(82), LSCF(6482), LSCF(8264) with the thickness of 0.85 mm were observed as 9.2×10-7 (mol/cm2 s), 1.7×10-7 (mol/cm2 s), and 1.0×10-7 (mol/cm2 s) in these cases at 1,153 K. The results indicated the...
Mechanism of surfactant in trichloroethene degradation in aqueous solution by sodium persulfate activated with chelated-Fe(II)
, Article Journal of Hazardous Materials ; Volume 407 , 2021 ; 03043894 (ISSN) ; Li, M ; Gu, X ; Danish, M ; Shan, A ; Ali, M ; Qiu, Z ; Sui, Q ; Lyu, S ; Sharif University of Technology
Elsevier B.V
2021
Abstract
The mechanism of surfactants in surfactant-in situ chemical oxidation (S-ISCO) coupled process for trichloroethene (TCE) degradation was firstly reported. The performance of TCE solubilization and inhibition of TCE degradation in three nonionic surfactants (TW-80, Brij-35, TX-100) in PS/Fe(II)/citric acid (CA) system was compared and TW-80 was evaluated to be the optimal surfactant in S-ISCO coupled process due to the best TCE solubilizing ability and minimal inhibition for TCE degradation (only 31.8% TCE inhibition in the presence of 1 g L−1 TW-80 surfactant). The inhibition mechanism in TCE degradation was also demonstrated by comparing the strength of ROSs and PS utilization. In the...
Degradation of BTEX in groundwater by nano-CaO2 particles activated with L-cysteine chelated Fe(III): enhancing or inhibiting hydroxyl radical generation
, Article Water Supply ; Volume 21, Issue 8 , 2021 , Pages 4429-4441 ; 16069749 (ISSN) ; Ali, M ; Cui, C ; Lyu, S ; Sharif University of Technology
IWA Publishing
2021
Abstract
The simultaneous oxidation performance of benzene, toluene, ethylbenzene, and xylene (BTEX) by nanoscale calcium peroxide particles (nCaO2) activated with ferric ions (Fe(III)) and the mechanism of the enhancement of BTEX degradation by L-cysteine (L-cys) were investigated. The batch experimental results showed that the nCaO2/Fe(III)/L-cys process was effective in the destruction of BTEX in both ultrapure water and actual groundwater. A proper amount of L-cys could enhance BTEX degradation due to the promotion of Fe(II)/Fe(III) redox cycles by the participation of L-cys, but an excessive presence of L-cys would cause inhibition. Adding 1.0 mM L-cys to the nCaO2/Fe(III) system, the...
Novel salep-based chelating hydrogel for heavy metal removal from aqueous solutions
, Article Polymers for Advanced Technologies ; Volume 27, Issue 8 , 2016 , Pages 999-1005 ; 10427147 (ISSN) ; Pourjavadi, A ; Monfared, A ; Khorasani, Z ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
A novel optimized chelating hydrogel was synthesized via graft copolymerization of acrylamide and 2-hydroxyethyl methacrylate (as two-dentate chelating co-monomer) onto salep (a multicomponent polysaccharide obtained from dried tubers of certain natural terrestrial orchids) using N,N′-methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. Reaction parameters (N,N′-methylenebisacrylamide and ammonium persulfate amounts as well as acrylamide/2-hydroxyethyl methacrylate weight ratio) affecting the water absorption of the chelating hydrogel were optimized using a systematic method to achieve a hydrogel with high swelling capacity as possible. Heavy metal ion adsorption...
Designing a new multifunctional peptide for metal chelation and Aβ inhibition
, Article Archives of Biochemistry and Biophysics ; Volume 653 , 2018 , Pages 1-9 ; 00039861 (ISSN) ; Asadbegi, M ; Khandan, V ; Amanzadi, A ; Sharif University of Technology
Academic Press Inc
2018
Abstract
According to the Amyloid hypothesis, as the foremost scientific explanation for Alzheimer Disease (AD), the neuropathology of AD is related to toxic fragments of amyloid beta (Aβ) protein. Based on this hypothesis, an attractive therapeutic approach was demonstrated to identify multifunctional peptides able to modulate Aβ pathologies as the source of AD. On this premise, a bifunctional polypeptide based on the iAβ5p lead compound, was designed to inhibit Aβ aggregation and free metal ions. Herein, the efficacy of this novel drug in Zn2+ and Cd2+ ion chelation was examined through an integrated technique comprising combined Docking, QM, and MD simulations. MD relaxation of a set of probable...
NIR emitting platinum pincer complexes based on the N^N^C ligand containing {benz[4,5]imidazo[1,2-a]pyrazin} aromatic system; synthesis, characterization and photophysical study
, Article Inorganica Chimica Acta ; Volume 511 , 2020 ; Hendi, Z ; Zhukovsky, D. D ; Sokolov, V. V ; Jamali, S ; Pavlovskiy, V. V ; Porsev, V. V ; Evarestov, R. A ; Tunik, S. P ; Sharif University of Technology
Elsevier S.A
2020
Abstract
In the present work we obtained a series of NIR luminescent platinum(II) complexes with a pincer N^N^C ligand based on the conjugated {benzoimidazo[1,2-a]pyrazine} system with the [Pt(N^N^C)L]n+ structural motif (L = phosphine, alkynyl or pyridine-type ligands). We have also synthesized two complexes with bidentate phosphines that demonstrate different types of coordination: 1) as chelating ligand (in case of 1,2-bis(diphenylphosphino)benzene), that led to de-coordination of pyridine ring of N^N^C ligand and formation of a [Pt(N^C)dppb]+ complex; 2) as a bridging ligand (in case of bis(diphenylphosphino)methane) between two {Pt(N^N^C)} fragments in a dimeric complex of type...
Cyclometalated platinum(II) complexes of 2,2′-bipyridine N-oxide containing a 1,1′-bis(diphenylphosphino)ferrocene ligand: structural, computational and electrochemical studies
, Article Dalton Transactions ; Volume 46, Issue 6 , 2017 , Pages 2013-2022 ; 14779226 (ISSN) ; Fereidoonnezhad, M ; Niazi, M ; Mosavi, S. T ; Habib Kazemi, S ; Kia, R ; Shirkhan, S ; Abdollahi Aghdam, S ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
The preparation and characterization of new heteronuclear-platinum(ii) complexes containing a 1,1'-bis(diphenylphosphino)ferrocene (dppf) ligand are described. The reaction of the known starting complex [PtMe(κ2N,C-bipyO-H)(SMe2)], A, in which bipyO-H is a cyclometalated rollover 2,2'-bipyridine N-oxide, with the dppf ligand in a 2:1 ratio or an equimolar ratio led to the formation of the corresponding binuclear complex [Pt2Me2(κ2N,C-bipyO-H)2(μ-dppf)], 1, or the mononuclear complex [PtMe(κ1C-bipyO-H)(dppf)], 2, respectively. According to the reaction conditions, the dppf ligand in 1 and 2 behaves as either a bridging or chelating ligand. All complexes were characterized by NMR spectroscopy....
The role of ligands in the synthesis of FePt nanoparticles
, Article Journal of Superconductivity and Novel Magnetism ; Volume 22, Issue 8 , 2009 , Pages 849-854 ; 15571939 (ISSN) ; Parhizgar, S ; Farahmandjou, M ; Aberomand, P ; Akhavan, M ; Sharif University of Technology
2009
Abstract
The monosize formation, the ability of self-assembly, and high coercivity after annealing are the properties that lead to the priority of FePt magnetic nanoparticles for the application in recording media. These nanoparticles were synthesized by the superhydride method. The effect of oleic acid and oleylamin ligands on the fabrication of nanocrystals and the stability of the FePt system has been studied. TEM, EDS, XRD, and spectrophotometer analysis show the formation of FePt nanoparticles dispersion in hexane and indicate that oleylamine increases the number of particles in the nucleation stage and decreases the size of the Pt core, whereas the oleic acid controls the shell of the particle...
Detection of dopamine receptors using nanoscale dendrimer for potential application in targeted delivery and whole-body imaging: synthesis and in vivo organ distribution
, Article ACS Applied Bio Materials ; Volume 5, Issue 4 , 2022 , Pages 1744-1755 ; 25766422 (ISSN) ; Aminzadeh Jahromi, N ; Ali, V ; Ebrahimpour, A ; Salehian, E ; Shafiee Ardestani, M ; Seyedhamzeh, M ; Ahmadi, S ; Sharifi, E ; Ashrafizadeh, M ; Rabiee, N ; Makvandi, P ; Sharif University of Technology
American Chemical Society
2022
Abstract
Dopamine is one of the most important neurotransmitters released by neurons in the central nervous system, and a variety of neurological illnesses and mental disorders are associated with impairments in the secretion and functionality of dopamine. Dopamine, depending on the type of receptors, can act as a stimulant or an inhibitor. In this study, dendrimer-conjugated dopamine was utilized as a chelating agent for Technetium-99m to investigate the organ distribution of this compound in vivo using the single-photon emission computed tomography (SPECT) technique. For this purpose, dendrimers were synthesized using polyethylene glycol diacid and citric acid precursors, and dopamine was...
Green metal-organic frameworks (MOFs) for biomedical applications
, Article Microporous and Mesoporous Materials ; Volume 335 , 2022 ; 13871811 (ISSN) ; Atarod, M ; Tavakolizadeh, M ; Asgari, S ; Rezaei, M ; Akhavan, O ; Pourjavadi, A ; Jouyandeh, M ; Lima, E. C ; Hamed Mashhadzadeh, A ; Ehsani, A ; Ahmadi, S ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Metal-organic frameworks (MOFs), known as highly ordered crystalline hybrid structures, are the products of coordination polymerization of transition metals and organic ligands. MOFs are best known for their extensive specific surface area, hierarchically porous and tailorable 1D, 2D, or 3D micro-and nanostructure, and acceptable biocompatibility. Because of the multiplicity of metallic and organic units used in MOFs synthesis, tailor-made MOFs can be synthesized to be served as building blocks of advanced biological materials and systems. Recently, synthesis of green MOFs has received much more attention for nanobiomedicine usage. We review herein synthesis and biomedical application of...
Comparison of the batch and breakthrough properties of stable and plain alginate microcapsules with a chelating resin and an ion exchanger in Ag+ adsorption
, Article Industrial and Engineering Chemistry Research ; Volume 47, Issue 17 , 5 August , 2008 , Pages 6742-6752 ; 08885885 (ISSN) ; Niibori, Y ; Mimura, H ; Ahmadi, S. J ; Sharif University of Technology
2008
Abstract
A comparative study on the uptake properties of alginate microcapsules containing Cyanex 302 extractant, Lewatite TP 214 chelating resin, and Amberlite 200CT strongly acidic ion exchanger has been conducted using Ag+ as the target ion. The study resulted in an analytical formula, as well as three phenomenological breakthrough formulas that are also applicable in other fixed-bed operations. It also demonstrated a close similarity of the uptake properties of alginate microcapsules (MCs) and the chelating resins. Advantages of MCs over chelating resins include ease of preparation, ability to immobilize different extractants, and, most remarkably, an enormous distribution factor (Kd ≈ 106...
Synthesis of bridged bithiazoles
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 19, Issue 2 , 2000 , Pages 65-66 ; 10219986 (ISSN) ; Sharif University of Technology
2000
Abstract
Bridged bithiazoles (5,5′-ethylene-4,4′-bithiazoles) are synthesized as a good chelating agent
Design, modeling and optimization of a piezoelectric pressure sensor based on thin-film PZT diaphragm contain of nanocrystalline powders
, Article 2009 6th International Symposium on Mechatronics and its Applications, ISMA 2009, Sharjah, 23 March 2009 through 26 March 2009 ; 2009 ; 9781424434817 (ISBN) ; Sheikhi, M. H ; Torkian, S ; Barzegar, A ; Masumi, E ; Mohammadi, S ; Sharif University of Technology
2009
Abstract
In this paper fabrication of a 0-3 ceramic/ceramic composite lead zirconate titanate, Pb(Zr0.52Ti0.48)O3 thin film has been presented and then a pressure sensor based on multilayer thin-film PZT diaphragm contain of Lead Zirconate Titanate nanocrystalline powders was designed, modeled and optimized. This multilayer diaphragm in general acts as sensor or actuator. ANSYS was used for simulation of diaphragm. Dynamics characteristics of this multilayer diaphragm have been investigated. By this simulation the effective parameters of the multilayer PZT diaphragm for improving the performance of a pressure sensor in different ranges of pressure are optimized. The optimized thickness ratio of PZT...
Low-temperature ultrasound synthesis of nanocrystals CoTiO3 without a calcination step: Effect of ultrasonic waves on formation of the crystal growth mechanism
, Article Advanced Powder Technology ; Volume 28, Issue 4 , 2017 , Pages 1109-1117 ; 09218831 (ISSN) ; Shahrouzianfar, A ; Ashiri, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
CoTiO3 nanocrystallites with an average diameter of 50 nm were synthesized successfully by the sonochemical method without a calcination step and using C10H16N2O8 (EDTA) as the chelating agent. To reach an in-depth understanding of the scientific basis of the proposed process, an in-detail analysis was carried out for characterization of nanoscale CoTiO3 particles via XRD, FTIR, FE-SEM and UV–vis diffuse reflectance spectroscopy (DRS). The crystallite size, average particle size and band gap are found to be 10.7 nm, in the range of 50 nm and 4.64 eV, respectively. The mechanism and the formation process of CoTiO3 in the sonochemical process were proposed. It was found that nanocrystals were...
Nano cobalt ferrite catalyzed coupling reaction of nitroarene and alkyl halide: An odorless and ligand-free rout to unsymmetrical thioether synthesis
, Article Catalysis Communications ; Volume 94 , 2017 , Pages 33-37 ; 15667367 (ISSN) ; Pourkaveh, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
This study describes an odorless protocol for the synthesis of unsymmetrical sulfides via cobalt ferrite (CoFe2O4) catalyzed cross-coupling reaction of nitroarenes with alkyl halides in the presence of thiourea as sulfur source under ligand-free conditions. The catalyst was recycled using external magnetic field and reused for ten consecutive runs in the reaction of nitrobenzene, thiourea and benzyl bromide without significant loss of activity. Apart from being magnetically separable, being inexpensive and air-stable are another important features of this catalytic system. All the products were formed in good yields and short reaction times. © 2017 Elsevier B.V
Turn-off chelation-enhanced fluorescence sensing of carbon dot-metallic deep eutectic solvent by imidazole-based small molecules
, Article Sensors and Actuators B: Chemical ; Volume 344 , 2021 ; 09254005 (ISSN) ; Bagheri, H ; Es-haghi, A ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Low accuracy, requirement of expensive instruments, derivatization and multi-step sample preparation, inconsistencies during the fabrication process, time-consuming procedures and utilization of eco-unfriendly chemicals are some limitations of various developed methods for detection of 4-methylimidazol (4-MeI). Herein, a rapid and miniaturized fluorescent probe based on the ultrasound‒assisted formation of carbon dots (CDs) in a metallic deep eutectic solvent (MDES) was developed and conveniently implemented to detect 4-MeI in commercial dark soft drinks. In-situ synthesis of CDs-chelated metals in the presence of the target analyte facilitates a kinetically fluorescence emission with no...