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    Exploration of an easily synthesized fluorescent probe for detecting copper in aqueous samples

    , Article Dalton Transactions ; Volume 46, Issue 45 , 2017 , Pages 15827-15835 ; 14779226 (ISSN) Sanmartín Matalobos, J ; García Deibe, A. M ; Fondo, M ; Zarepour Jevinani, M ; Domínguez González, M. R ; Bermejo Barrera, P ; Sharif University of Technology
    Royal Society of Chemistry  2017
    An easily synthesized fluorescent probe for detecting copper in aqueous samples, with a short response time and at neutral pH, has been investigated. Through the chelation of Cu2+ ions or by binding to CuO nanoparticles, the fluorescence emission of the 2-(aminomethyl)aniline derivative H2L is quenched by over 50%. Spectroscopic determination of the association constants of H2L with some metal ions showed that the ligand has a higher affinity toward Cu2+ than toward other d-block metal ions. The comparative bonding ability of the aniline-based fluorescent probe in d-block metal complexes was studied in solution by a combination of UV-Vis, 1H NMR and mass spectrometry analyses. Besides these,... 

    Fabrication of gas ionization sensor using carbon nanotube arrays grown on porous silicon substrate

    , Article Sensors and Actuators, A: Physical ; Volume 162, Issue 1 , 2010 , Pages 24-28 ; 09244247 (ISSN) Nikfarjam, A ; Iraji Zad, A ; Razi, F ; Mortazavi, S. Z ; Sharif University of Technology
    We fabricated gas sensors based on field ionization from multiwalled carbon nanotube (MWCNT) arrays grown on porous silicon templates. MWCNTs were grown through thermal chemical vapor deposition. We measured breakdown voltages, discharge and pre-discharge currents of the device for various gases in different concentrations. Our gas ionization sensors (GIS) presented good sensitivity, selectivity and short response time. The GISs based on porous substrates showed higher discharge current and good mechanical stability in comparison to those which were fabricated on polished silicon substrates. Additionally, we applied a high electric field to align CNTs. This increased the pre-breakdown... 

    Application of carbon nanoparticle/chitosan modified electrode for the square-wave adsorptive anodic striping voltammetric determination of Niclosamide

    , Article Electrochemistry Communications ; Volume 12, Issue 1 , 2010 , Pages 66-69 ; 13882481 (ISSN) Ghalkhani, M ; Shahrokhian, S ; Sharif University of Technology
    A new modified electrode formed by carbon nanoparticle/chitosan film (CNP/CS) was used for electrocatalytic reduction of Niclosamide (NA). The electrochemical behavior of NA at the CNP/CS modified electrode was investigated in detail by the means of cyclic voltammetry. The reduction mechanism of NA, corresponds to the redox chemistry of nitro group, was thoroughly investigated. The effect of the experimental parameters e.g. potential and time of accumulation, pH of the buffered solutions and potential sweep rate on the response of the electrode was studied. The prepared electrode showed high stability and uniformity in the composite film, short response time, good reproducibility and an...