فهرست مقالات Nano Grapheme

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  1 - Influence of nano graphene on water absorption in polyester/vinylester blend gel coats
  Zeinab Rajabtabar Morteza Ehsani Azam Ghadami Yasser Amani
  Water absorption characteristics of composite materials and gel coats are crucial for their applications in marine industry. The physical and mechanical properties of composite parts are influenced by moisture. Water absorption of five gel coat compositions based on epo چکیده کامل

  Water absorption characteristics of composite materials and gel coats are crucial for their applications in marine industry. The physical and mechanical properties of composite parts are influenced by moisture. Water absorption of five gel coat compositions based on epoxy vinylester resin and neopentylglycol unsaturated polyester resin and their blends was studied in this work. The influence of nanographene addition on the water absorption of these gel coats was also investigated. The results showed that epoxyvinylester resin had the lowest and neophentylglycol unsaturated polyester resin had the highest water absorption levels, and their blends, as expected, showed the same behavior. TEM, SEM and XRD were used to analyze and characterize the dispersion and distribution of nanographene particles in the polymer matrices. The results showed both dispersed and non-dispersed flakes in the polymer matrices. It was also shown that the addition of nanographene resulted in gel coats with lower water absorption levels. پرونده مقاله
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  2 - Separation of Trace Amount Zn (II) Using Additional Carbonyl and Carboxyl Groups Functionalized-Nano Graphene
  A. Moghimi
  10.22034/jchr.2018.544012
  A novel and selective method for the fast determination of trace amounts of Zn(II)ions in water samples has been developed.  The first additional carbonyl and carboxyl functionalized-nano graphene (SPFNano graphene). The presence of additional carbonyl and carboxyl gro چکیده کامل

  A novel and selective method for the fast determination of trace amounts of Zn(II)ions in water samples has been developed.  The first additional carbonyl and carboxyl functionalized-nano graphene (SPFNano graphene). The presence of additional carbonyl and carboxyl groups located at the edge of the sheets makes GO sheets strongly hydrophilic, allowing them to readily swell and disperse in water. Based on these oxygen functionalities, different model structures of GO were used as absorbent for extraction of Zn (II)   ions by solid phase extraction method. The complexes were eluted with HNO3 (2M)10% V.V-1 methanol in acetone and determined the analyte by flame atomic absorption spectrometry.  The procedure is based on the selective formation of Zn (II) at optimum pH by elution with organic eluents and determination by flame atomic absorption spectrometry. The method is based on complex formation on the surface of the ENVI-18 DISKTM disks modified carbonyl and carboxyl functionalized-nano graphene oxide molecules covalently bonded together followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effect of potential interfering ions, pH, SPFNano graphene, amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about 1000mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be 456± 3 µg for Zn2+.The limit of detection of the proposed method is 5ng per 1000mL.The method was applied to the extraction and recovery of Zn in different water samples. پرونده مقاله