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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...
A comparative study on hydrogen interaction with defective graphene structures doped by transition metals
, Article Physica E: Low-Dimensional Systems and Nanostructures ; Vol. 60 , June , 2014 , pp. 104-111 ; ISSN: 13869477 ; Saboohi, Y ; Sharif University of Technology
Abstract
In the present work, the interaction of hydrogen molecules with defective graphene structures doped by transition metal (TM) atoms is investigated by using first principles density functional theory (DFT). Defective graphene structures include Stone-Wales (SW), 585 and 555-777 and transition metals include early TMs, i.e. scandium (Sc), titanium (Ti) and vanadium (V). It is found that in comparison with the pristine graphene, presence of defects significantly enhances the metal binding. Among three defects, 585 divacancy leads to the strongest binding between graphene and metal. Hydrogen adsorption is then evaluated by sequential addition of hydrogen molecules to the system. The results...
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...
Developing potentiometric sensors for scandium
, Article Sensors and Actuators B: Chemical ; Volume 348 , 2021 ; 09254005 (ISSN) ; Legin, E ; Legin, A ; Yaghmaei, S ; Nechaev, A ; Babain, V ; Kirsanov, D ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Scandium is a rare earth element that is not very abundant on Earth, however in recent years due to the employment of scandium in various high-tech fields the interest in the analytical chemistry of this metal is growing. Currently, the methods for scandium quantification are mainly based on inductively coupled plasma atomic emission and mass-spectrometry and to the best of our knowledge no potentiometric sensors for scandium detection were reported so far. This study is devoted to the development of simple and cost-effective ion-selective sensors for quantification of Sc3+ in aqueous media. Employing the variety of lipophilic ligands suggested in liquid extraction for separation of...
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...