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Synthesis of gadolinium(III) and samarium(III) complexes of new potentially heptadentate (N4O3) tripodal Schiff base ligands, and a theoretical study
, Article Polyhedron ; Volume 24, Issue 12 , 2005 , Pages 1478-1486 ; 02775387 (ISSN) ; Nouri, S. M ; Keypour, H ; Bagherzadeh, M ; Sharif University of Technology
2005
Abstract
Two new potentially heptadentate N4O3 Schiff base ligands {N[(CH2)3NCH(2-OH-3,5-t-Bu2C 6H2)]3} (H3L1) and {N[(CH2)3NCH(2-OH-3,5-t-Bu2C6H 2)]2 [(CH2)2-NCH(2-OH-3,5-t-Bu 2C6H2)]} (H3L2) were synthesized and characterized by various spectroscopic methods. The heptadentate N4O3 Schiff bases, H3L1 and H 3L2, were derived from the condensation reaction of two tripodal tetraamine ligands, tris(3-aminopropyl)amine and (2-aminoethyl)-bis(3- aminopropyl)amine with 3 equiv. of 3,5-di-tert-butylsalicylaldehyde, respectively. The neutral gadolinium(III) and samarium(III) complexes, [Ln(L)], of these bulky ligands and also a gadolinium(III) complex of a previously known ligand,...
Using commercial calcium ionophores to make lanthanide sensors
, Article Journal of Radioanalytical and Nuclear Chemistry ; Volume 331, Issue 4 , 2022 , Pages 1751-1758 ; 02365731 (ISSN) ; Saveliev, M ; Legin, A ; Yaghmaei, S ; Babain, V ; Kirsanov, D ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
Developing chemical sensors with pronounced sensitivity towards lanthanides is a very important task related to the analytical control of industrial processes in nuclear industry. Various diamides of organic acids were shown to be very effective for such sensing applications when employed as ligands in plasticized polymeric membranes of potentiometric sensors. The chemical structures of some of these ligands (diamides of diglycolic acid) are very similar to those suggested in 80’s as Ca(II) ionophores that were later commercialized. We have hypothesized that commercial ionophores ETH 129 (N,N,N′,N′-tetra[cyclohexyl] diglycolic acid diamide) and ETH 5234...
Synthesis of Lanthanide (III) Macrocyclic Schiff Base Complexes Containing Pyridine and their Decomposition in Aqueous Solution
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
This study involved the synthesis, structural characterization and studies of gadolinium (III) hexaaza macrocyclic Schiff base complexes containing pyridine head and their decomposition in aqueous solution.There are many applications of lanthanide(III) macrocyclic complexes as medicine and in the biological systems, as magnetic resonance imaging (MRI) agents, and etc.These applications require that the Gd(III) complexes be resistant to gadolinium ion release under physiological conditions.
We considered planer macrocyclic ligands as a means to obtain highly stable complexes of Gd(III). Symmetric [2+2] Schiff base macrocyclic derived from 2,6-diacetylpyridine with amines would exhibit...
We considered planer macrocyclic ligands as a means to obtain highly stable complexes of Gd(III). Symmetric [2+2] Schiff base macrocyclic derived from 2,6-diacetylpyridine with amines would exhibit...
Effect of Doping la/nd in pr Site and fe/cu in ni Site on Thermal Stability of the Pr2NiO4+δ as the Cathode of Intermediate Temperature Solid Oxide Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Fagihi Sani, Mohammad Ali (Supervisor)
Abstract
Solid oxide fuel cells (SOFCs) are a route to highly efficient and clean power, which have been attracting interest due to the issues associated with the ever-increasing energy demand and pollution. However, their commercialization is hindered by the high operating temperatures (700-1000℃). One of the challenges faced by intermediate temperature solid oxide fuel cells (IT-SOFCs) with operating temperature in the range of 500-700℃ is the increased overpotentials of the components, especially cathode. Lanthanide nickelates (Ln2NiO4+δ, Ln = La,Pr,Nd) with mixed ionic and electronic conduction (MIEC) have already been introduced as promising IT-SOFC cathode materials. Among them, Pr2NiO4+δ...
Development of Miniaturized Electrochemical Sensors Based on Ion-Selective Membrane for Environmental Applications
, Ph.D. Dissertation Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Legin, Andrey (Supervisor) ; Kirsanov, Dmitry (Supervisor) ; Babain, Vasiliy (Supervisor)
Abstract
The first study of the present research aims to the possibility of developing simple, accurate and selective potentiometric sensors for the detection of scandium ions in aqueous solution, which is done for the first time. In this study, a sensor array consisting of 17 miniaturized potentiometric sensors based on polymeric membranes containing various ion-extracting ligands were designed and fabricated. Ligands as the active component of the membranes included phosphine oxides and diamides of various organic acids, which were used in the extraction of rare earth metal ions. The possibility of using these extractants in the polymer matrix of membranes for the development of scandium-sensitive...
Application of NaYF4:Yb/Er/Tm UCNPs in Array-Based Sensing of Neurotransmitters: From a Single Particle to a Multichannel Sensor Array
, Article ACS Applied Materials and Interfaces ; 2020 ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
American Chemical Society
2020
Abstract
A novel multichannel sensor array has been designed using a single, yet multiemissive lanthanide-doped upconversion nanoparticle (UCNP). The energy levels of lanthanide ions gave rise to several emission bands which were exploited as individual sensor elements for the recognition of four important neurotransmitters (NTs): dopamine, norepinephrine, levodopa, and serotonin. At alkaline conditions, the oxidation products of these NTs quenched the fluorescence emissions of UCNPs with different quenching degrees. The resulting fingerprint multichannel emission profiles from NaYF4:Yb/Er/Tm UCNPs allowed the discrimination of NTs with excellent accuracy. The recognition was further verified in...
Geochemical characteristics of rare earth elements in different types of soil: a chemometric approach
, Article Chemosphere ; Volume 184 , 2017 , Pages 673-678 ; 00456535 (ISSN) ; Behkami, S ; Yusoff, I ; Md Zain, S. B ; Bakar, N. K. A ; Bakar, A. F. A ; Alias, Y ; Sharif University of Technology
Abstract
Rare earth elements (REEs) are becoming significant due to their huge applications in many industries, large-scale mining and refining activities. Increasing usage of such metals pose negative environmental impacts. In this research ICP-MS has been used to analyze soil samples collected from former ex-mining areas in the depths of 0–20 cm, 21–40 cm, and 41–60 cm of residential, mining, natural, and industrial areas of Perak. Principal component analysis (PCA) revealed that soil samples taken from different mining, industrial, residential, and natural areas are separated into four clusters. It was observed that REEs were abundant in most of the samples from mining areas. Concentration of the...