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    Silver nanoparticles-polyaniline nanocomposite for microextraction in packed syringe

    , Article Chromatographia ; Vol. 77, issue. 5-6 , 2014 , pp. 397-403 ; ISSN: 00095893 Bagheri, H ; Banihashemi, S ; Sharif University of Technology
    Abstract
    A rapid, convenient and reliable method for microextraction in packed syringe (MEPS) of the loop diuretic furosemide (FUR) in urine along with high-performance liquid chromatography (HPLC) was developed. A nanocomposite based on silver nanoparticles/polyaniline (Ag-NPs/PANI) was synthesized and used as the MEPS packing material. This nanocomposite was prepared conveniently using interfacial polymerization without the need for any templates or functional dopants. The feasibility of the synthesized nanocomposites was examined by isolation of FUR from diluted urine samples. After extraction, the analyte was desorbed by 200 μL of methanol. It was then dried and the residue was dissolved in 30 μL... 

    Sol-gel-based silver nanoparticles-doped silica - Polydiphenylamine nanocomposite for micro-solid-phase extraction

    , Article Analytica Chimica Acta ; Volume 886 , July , 2015 , Pages 56-65 ; 00032670 (ISSN) Bagheri, H ; Banihashemi, S ; Sharif University of Technology
    Elsevier  2015
    Abstract
    A nanocomposite of silica-polydiphenylamine doped with silver nanoparticles (Ag-SiO2-PDPA) was successfully synthesized by the sol-gel process. For its preparation, PDPA was mixed with butanethiol capped Ag nanoparticles (NPs) and added to the silica sol solution. The Ag NPs were stabilized as a result of their adsorption on the SiO2 spheres. The surface characteristic of nanocomposite was investigated using scanning electron microscopy (SEM). In this work the Ag-SiO2-PDPA nanocomposite was employed as an efficient sorbent for micro-solid-phase extraction (μ-SPE) of some selected pesticides. An amount of 15 mg of the prepared sorbent was used to extract and... 

    Core-shell electrospun polybutylene terephthalate/polypyrrole hollow nanofibers for micro-solid phase extraction

    , Article Journal of Chromatography A ; Volume 1434 , 2016 , Pages 19-28 ; 00219673 (ISSN) Bagheri, H ; Rezvani, O ; Banihashemi, S ; Sharif University of Technology
    Elsevier B.V  2016
    Abstract
    In the present work, a new micro-solid phase extraction (μ-SPE) sorbent as an extracting medium based on core-shell nanofibers was synthesized by electrospinning. The core-shell nanofibers of polyvinylpyrrolidone-Polybutylene terephthalate/polypyrrole (PVP-PBT/PPy) were electrospun and subsequently, modified hollow nanofibers were prepared by removing the central PVP moiety. Moreover, conventional PBT/PPy was also prepared for the comparison purposes. The homogeneity and the porous surface structure of the core-shell nanofibers were confirmed by scanning electron microscopy (SEM). The applicability of the fabricated nanofibers-coating was examined by immersed μ-SPE of some selected triazine... 

    A polythiophene–silver nanocomposite for headspace needle trap extraction

    , Article Journal of Chromatography A ; Volume 1460 , 2016 , Pages 1-8 ; 00219673 (ISSN) Bagheri, H ; Banihashemi, S ; Jelvani, S ; Sharif University of Technology
    Elsevier B. V 
    Abstract
    A nanocomposite consisting of polythiophene–silver was prepared and implemented as a desired sorbent for headspace needle trap extraction. Colloidal silver nanoparticles (Ag NPs) with narrow size distribution and high stability were synthesized in water–in–oil microemulsion. This simple procedure was adapted to prepare highly monodispersed Ag NPs, starting from an initial synthesis in sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles. Polythiophene (PT) was synthesized by chemical oxidative polymerization in the presence of anhydrous ferric chloride while its polymeric structure was confirmed by Fourier transform infrared spectrometry (FTIR). Eventually, the prepared PT was... 

    A metal organic framework-polyaniline nanocomposite as a fiber coating for solid phase microextraction

    , Article Journal of Chromatography A ; Volume 1431 , 2016 , Pages 27-35 ; 00219673 (ISSN) Bagheri, H ; Javanmardi, H ; Abbasi, A ; Banihashemi, S ; Sharif University of Technology
    Elsevier B. V 
    Abstract
    A metal organic framework-polyaniline (MOF/PANI) nanocomposite was electrodeposited on a stainless steel wire and used as a solid phase microextraction (SPME) fiber coating. The electropolymerization process was carried out under a constant deposition potential and applied to the corresponding aqueous electrolyte containing aniline and MOF particles. The employment of MOFs with their large and small cages and 3-D structures in synthesizing a nanocomposite was assumed to be efficient constitutes to induce more non-smooth and porous structures, approved by scanning electron microscopy (SEM) images. Three different MOFs were incorporated to synthesize the desired nanocomposites and the... 

    An intelligent hybrid classification algorithm integrating fuzzy rule-based extraction and harmony search optimization: Medical diagnosis applications

    , Article Knowledge-Based Systems ; Volume 220 , 2021 ; 09507051 (ISSN) Mousavi, S. M ; Abdullah, S ; Akhavan Niaki, S. T ; Banihashemi, S ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Uncertainty is a critical factor in medical datasets needed to be overcome for increasing diagnosis efficiency. This paper proposes an intelligent classification algorithm comprising a fuzzy rule-based approach, a harmony search (HS) algorithm, and a heuristic algorithm to classify medical datasets intelligently. Two fuzzy approaches, as well as orthogonal and triangular fuzzy sets, are first utilized to define the attributes of data. Then, an HS algorithm is integrated with a heuristic to generate fuzzy rules to select the best rules in the fuzzy rule-based systems. Moreover, to improve the performance of the proposed classification approach, a three-phase parameter tuning approach is...