فهرس المقالات Multiwalled carbon

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  1 - Solid-phase Extraction Using Modified Carbon Nanotube and Cupferron Ligand for Preconcentration and Determination of Trace Amounts of Copper in Real Samples
  Maasoomeh Ghasemi Ali Moghimi Mohammad-Ali Karimi Shahla Mozaffari
  A solid phase extraction procedure for simultaneous separation and preconcentration of traceamounts of Cu+2 ion from various real samples prior to its determination by flame atomicabsorption spectrometry has been developed. The proposed method is based on the utilizatio أکثر

  A solid phase extraction procedure for simultaneous separation and preconcentration of traceamounts of Cu+2 ion from various real samples prior to its determination by flame atomicabsorption spectrometry has been developed. The proposed method is based on the utilization ofmultiwalled carbon nanotube in combination with Cupferron ligand as a solid phaseextractant. The influences of the analytical parameters, including pH, amounts of ligand andadsorbent, sample volume, volume and concentration of eluent, flow rates of solution and ,interference effects from the foreign metal ions were investigated for the optimum recoveries of theanalyte ion. The optimum pH for the separation of Cu+2 ion on the new sorbent was 7.0. Therelative standard deviation (RSDs) and the recoveries of standard addition for this method werelower than 5 % and 95-100 %, respectively. A sample volume of 200 mL resulted in apreconcentration factor of 100. The proposed procedure was successfully applied to thedetermination of copper in various real samples with satisfactory results. تفاصيل المقالة
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  2 - An efficient platform based on cupper complex-multiwalled carbon nanotube nanocomposite modified electrode for the determination of uric acid
  Mohammad Mehdi Foroughi
  10.22034/jna.2020.1875990.1152
  A new voltammetric sensor for determination of uric acid (UA) by Cupper complex- multiwalled carbon nanotube (Cu-complex-CNT) nanocomposite modified carbon paste electrode (CPE) is reported. The electrocatalytic behavior of the Cu-complex-CNT nanocomposite modified CPE أکثر

  A new voltammetric sensor for determination of uric acid (UA) by Cupper complex- multiwalled carbon nanotube (Cu-complex-CNT) nanocomposite modified carbon paste electrode (CPE) is reported. The electrocatalytic behavior of the Cu-complex-CNT nanocomposite modified CPE were studied in pH 2.0 phosphate buffer solution by chronoamperometry (CA) and cyclic voltammetry (CV) in the presence of uric acid. Due to the excellent electrocatalytic activity, enhanced electrical conductivity and high surface area of the Cu-complex-CNT, determination of uric acid with well-defined peaks was achieved at the Cu-complex-CNT modified electrode. The catalytic peak current obtained, was linearly dependent on the UA concentrations in the range of 0.66 – 350.0µM with sensitivity of 0.05 µA µM-1. The detection limits for UA were 0.075µM, The diffusion coefficient for the oxidation of UA at the modified electrode was calculated as (4.1±0.05) ×10−5 cm2 s−1. The proposed sensor was successfully examined for real sample analysis with urine and human serum and revealed stable and reliable recovery data. تفاصيل المقالة
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  3 - An efficient platform based on cupper complex-multiwalled carbon nanotube nanocomposite modified electrode for the determination of uric acid
  Mohammad Mehdi Foroughi
  10.22034/jna.2020.677398
  A new voltammetric sensor for determination of uric acid (UA) by Cuppercomplex- multiwalled carbon nanotube (Cu-complex-CNT) nanocomposite modifiedcarbon paste electrode (CPE) is reported. The electrocatalytic behavior of theCu-complex-CNT nanocomposite modified CPE was أکثر

  A new voltammetric sensor for determination of uric acid (UA) by Cuppercomplex- multiwalled carbon nanotube (Cu-complex-CNT) nanocomposite modifiedcarbon paste electrode (CPE) is reported. The electrocatalytic behavior of theCu-complex-CNT nanocomposite modified CPE was studied in pH 2.0 phosphatebuffer solution by chronoamperometry (CA) and cyclic voltammetry (CV) in thepresence of uric acid. Due to the excellent electrocatalytic activity, enhancedelectrical conductivity and high surface area of the Cu-complex-CNT, determinationof uric acid with well-defined peaks was achieved at the Cu-complex-CNT modifiedelectrode. The catalytic peak current obtained, was linearly dependent on theUA concentrations in the range of 0.66 – 350.0μM with sensitivity of 0.05 μAμM-1. The detection limits for UA were 0.075μM, The diffusion coefficient for theoxidation of UA at the modified electrode was calculated as (4.1±0.05) ×10−5 cm2s−1. The proposed sensor was successfully examined in real sample analysis withurine and human serum and revealed stable and reliable recovery data. تفاصيل المقالة
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  4 - New method for preparation of MWCNT-SO3H as an efficient and reusable catalyst for the solvent-free synthesis of 3,4-dihydropyrimidin-2(1H)-ones/thiones
  Leila Moradi Gholam Reza Najafi Hakimeh Saeidiroshan
  Multiwalled carbon nanotubes (MWCNTs) have been functionalized with -SO3H groups using new three steps chemical routes. Firstly, OH groups have been attached to CNT surfaces through a radical reaction. The second step involves converting the hydroxyl groups into the oxi أکثر

  Multiwalled carbon nanotubes (MWCNTs) have been functionalized with -SO3H groups using new three steps chemical routes. Firstly, OH groups have been attached to CNT surfaces through a radical reaction. The second step involves converting the hydroxyl groups into the oxide one and last step included the attachment of –SO3H groups on the MWCNTs surfaces in the presence of 1-butyl-3-methyl imidazolium tetrafluoroborate [bmim]BF4 ionic liquid as catalyst. Functionalized MWCNTs were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman Spectroscopy. Obtained product have be used as acidic nano catalyst in the Biginelli reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives. The reaction was performed under solvent-free conditions with excellent yields and short reaction times in the presence of a reusable efficient catalyst. تفاصيل المقالة
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  5 - Preconcentration of Zn(II) from Sample Water by Phenyl-iminodiacetic Acid Grafted Multiwalled Carbon Nanotubes
  A. Moghimi
  10.22034/jchr.2018.544002
  : phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes were prepared by grafted phenyl-iminodiacetic acid groups onto multi-walled carbon nanotubes via a diazotation reaction. The stability of chemically phenyl-iminodiacetic acid grafted multiwalled carbon nan أکثر

  : phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes were prepared by grafted phenyl-iminodiacetic acid groups onto multi-walled carbon nanotubes via a diazotation reaction. The stability of chemically phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes in concentrated hydrochloric acid which was then used as a recycling and pre-concentration reagent for further uses of phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes. The application of this  phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes for sorption of a series of metal ions was performed by using different controlling factors such as the pH of metal ion solution and the equilibration shaking time by the static technique. Zn(II) was found to exhibit the highest affinity towards extraction by these  phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes phases. The pronounced selectivity was also confirmed from the determined distribution coefficient (Kd) of all the metal ions, showing the highest value reported for Zn(II) to occur by  phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes. The potential applications of  phenyl-iminodiacetic acid grafted multiwalled carbon nanotubes for selective extraction of Zn(II) to occur from aqueous solution were successfully accomplished as well as pre- concentration of low concentration of Zn(II) (60 pg ml-1) from natural tap water with a pre-concentration factor of 100 for Zn(II) off-line analysis by flame atomic absorption analysis.  تفاصيل المقالة