فهرست مطالب

Journal of Nanoanalysis
Volume:4 Issue: 4, Dec 2017

  • تاریخ انتشار: 1396/09/10
  • تعداد عناوین: 10
  • Saeed Sadeghpour, Saghar Abedini Pages 265-271

    Protein isolate is used in the food industry in order to process and stabilise food foams. Thereforethere has been a great deal of interest and research in order to understand the effect of processingparameters on the functional properties of the isolate. The major purpose of this research is to studythe foamability of the different proteins - starch nano-particle system. The results from experimentsrevealed that the foam properties can vary significantly for certain protein solutions; however, theinterfacial properties seem to be constant and the most important results from the experiments areA) in starches samples, adding protein had no significant effect on viscosity, consequently, there wasno drainage limitation B) for starches sample surface tension is not limiting factor C) At same starchconcentration Egg White protein (EWP) foams had a much higher drainage half-life time comparedwith pea protein (PPI) foams. The affected properties on foam stability, such as viscosity, surfacetension and pH were compared to discover the best solution for foam stability.

    Keywords: Surface Tension, EWP, PPI, Nano-Particle, Overrun
  • Sadegh Afshari, Jaber Jahanbin Sardroodi, Hakimeh Mohammadpour Pages 272-279

    Quantum transport properties of pure and functioned infinite lead-connection region-lead systembased on the zigzag graphene nanoribbon (2-zGNR) have been investigated. In this work the effectof the doping functionalization on the quantum transport of the 2-zGNR has been computationallystudied. Also, the effect of the imposed gate voltages (-3.0, 0.0 and +3.0 V) and bias voltages 0.0 to2.0 V have been studied. The results were presented as the current versus the bias voltage (I-Vb)curves with unique properties for per studied systems, showing one or two negative differentialresistances (NDR). The NDR region was discussed and interpreted in the terms of the transmissionspectrum and its integral inside of the corresponding bias window. Also, the partial atomic chargedistribution in the center part of the system’s scattering region containing carbon atoms at the leftand right sides of substituted atoms which are connected to substituted atoms has been investigatedfor different bias voltages.

    Keywords: graphene nanoribbon, partial atomic charge, NEGF, NDR, doping
  • Zahra Rasouli, Mohammad Yousefi, Susan Samadi, Khadijeh Kalateh, Maryam Bikhof Torbati Pages 280-289

    In this study, CeO2 hollow spherical nanoparticles, CeO2/SiO2 @ CeO2 core/shell composites,and hollow CeO2/SiO2 sensors were synthesized and their microstructures were researched byFT-IR, XRD, FESEM, EDX and BET analyses. The peaks observed in the FT-IR spectra of the synthesizedsamples corresponded to Ce-O stretching vibration (ca. 566 cm-1) and O-Si-O bendingvibration (ca. 470 cm-1). XRD diffraction patterns showed peaks at 2θ values in the 28.95° ,33.74°, 47.75° , 57.04°, 59.52° ,and 69.4° confirming cubic phase of CeO2. The FESEM imagesshowed that the particle shape was approximately spherical. The results of BET showed that,surface area of the CeO2 hollow spherical nanoparticles, CeO2/SiO2 @ CeO2 and hollow CeO2/SiO2 core/shell particles were 102.78, 80.49, and 119.71 m2/g, respectively. The nanosizedmetal oxides were used to quantitatively and qualitatively identify 1-propanol, 2-propanol,ethanol and methanol. The results showed that, the hollow CeO2/SiO2 core/shell was of largerpotentials for qualitative identification of 1-propanol and quantitative measurement of 2-propanol and ethanol.

    Keywords: Cerium dioxide, Core, Shell, Hollow, sensor, Volatile organic compounds
  • Samira Rahmani-Nezhad, Shima Dianat, Mina Saeedi, Abbas Hadjiakhoondi Pages 290-298

    Development of green and efficient procedures for the synthesis of metallic nanoparticleshas emerged as a significant topic in the field of nanotechnology. In this respect, using naturalresources,especially plant extract has attracted lots of attention; plant extract is a promisingalternative to traditional and chemical techniques. The plant Mucuna pruriens L. contains highconcentration of L-dopa in the seeds; it has been used as a nerve tonic for nervous systemdisorders including Parkinson’s disease. In this work, a rapid and efficient synthesis of stablemagnesium oxide nanoparticles (MgO NPs) using aqueous extract of Mucuna pruriens seedswere reported. The biologically synthesized MgO NPs were characterized by UV–Visible andFourier transform infrared (FTIR) spectroscopy as well as X-ray diffraction (XRD), scanning andtransmission electron microscopy (SEM and TEM). The potential of MgO nanoparticles in thedegeneration of methyl orange (MO) and methylene blue (MB) dyes were assessed in differentconditions. The results of these investigations showed that the synthesized MgO NPs havea good catalytic activity in the removal of both dyes. Biological study of biosynthesized MgONPs showed moderate antibacterial property against four strains of bacteria and a very goodantioxidant activity.

    Keywords: Nano MgO, Plant-mediated synthesis, Mucuna pruriens L, Biological activity, Catalytic property
  • Jamal Davarpanah, AliReza Kiasat Pages 299-306

    In the present study, application of porous acidic catalyst functionalized with an imidazoleionic liquid ([SBA-Im]HSO4) as a phase transfer catalyst for the facile preparation of benzylthiocyanates and azides in water has been described. The catalyst has been characterized byFourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmissionelectron microscopy (TEM), thermogravimetric analysis (TGA) and derivative thermogravimetricanalysis (DTG). The polymeric phase transfer catalyst, easily recovered by simplefiltration, shows no appreciable loss of activity when recycled several times.

    Keywords: Phase transfer catalyst, Nucleophilic substitution, Porous catalyst, Benzyl halides
  • Majid Masoumi, Ali Morad Rashidi, Mohammadmehdi Choolaei, Saeed Sadeghpour Pages 307-312

    Graphene films were fabricated over synthesized MCM-41 nanocatalyst by chemical vapordeposition method, and the reaction was carried in atmospheric pressure at 750˚C. Acetylenegas used as a carbon precursor and the synthesis reaction took place in hydrogen atmosphere.Mesoporous MCM-41 was synthesized at room temperature, using wet chemical method. Thesynthesized metal free catalyst was characterized by XRD and N2 adsorption isotherms. Thecatalytically synthesized graphene layers were characterized by Raman spectroscopy, scanningelectron microscopy (SEM), and transmission electron microscopy (TEM). The results indicatedthat the favorable effect of MCM-41 with high BET surface area (908.76 m2/g) as an activemetal free nanocatalyst for fabricating graphene layers with high level of purity and homogeneity.Because of simplicity, easy purification, and high yield of graphene synthesis offered bythis method, it is possible to use it in larger scales.

    Keywords: Graphene, CVD method, Nanocatalyst, MCM-41
  • Amanollah Zarei Ahmady, Seyyed Jafar Saghanezhad, Neda Mohtasham Pages 313-319

    Sulfuric acid functionalized magnetic nanocatalyst (SAMNC) has been prepared as an efficientacidic and applied in the one-pot preparation of 2,3-dihydroquinazolin-4 (1H) -one derivatives.This catalyst has been characterized by FT-IR, SEM, and VSM. According to the obtainedresults, including time, yield and recyclability, SAMNC could be considered as an efficient catalystfor organic transformations.

    Keywords: Sulfuric acid magnetic nanocatalyst, Solvent-free, 3-Dihydroquinazolin-4(1H)-ones, One-pot
  • HamidReza Ghorbani Pages 320-323

    In this paper, Chitosan-copper nanoparticles were successfully coated onto the Kraft paperusing a dip coating process. First, chitosan-copper nanoparticles solution was prepared byreduction method and the use of ultrasonic radiation. It was employed copper sulphate pentahydrateas precursor salt, NaOH as a reducing agent and Chitosan as capping agent to prepareChitosan-copper nanoparticles solution. The solution was analyzed by UV-Vis spectroscopyand dynamic light scattering (DLS). After the coating process, the coated Kraft paper was characterizedby X-Ray diffraction and scanning electron microscopy (SEM). Then, the antimicrobialactivity of the Kraft paper, in contrast to Bacillus subtilis and Escherichia coli was measuredby disc diffusion method.

    Keywords: Chitosan, Copper, nanoparticles, Kraft paper, Coating
  • Hamid Yousefi, Ahmad Gholizadeh, Zahra Mirbeig Sabzevari, Azim Malekzadeh Pages 324-333

    In this paper, La0.55Ca0.45A0.5Co0.5O3(A=Mg, Mn) nanoparticles were synthesized by citratemethod. The samples were characterized using the techniques of using X-ray diffraction(XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and UVVisspectroscopy. The structure was analyzed by Rietveld fitting of the XRD pattern by usingX’Pert package and Fullprof program, these shows that the samples have perovskite structure.The calculated values of crystallite size, particle size and band gap energy of La0.55Ca0.45Mg0.5Co0.5O3 are much less than La0.55Ca0.45Mg0.5Co0.5O3. The effects of three operational parametersincluding irradiation time, pH, and the catalyst amount on the photocatalytic activity ofthe product on the degradation of methyl blue (MB) under solar condition were studied. Thephotocatalytic degradation efficiency of MB solution over La0.55Ca0.45Mn0.5Co0.5O3 nanoparticlesis higher than that over La0.55Ca0.45Mg0.5Co0.5O3 nanoparticles. 96 % degradation is obtainedin an aqueous solution at pH=2.33 and containing 30 mg La0.55Ca0.45Mg0.5Co0.5O3 catalystafter 30 minutes.

    Keywords: nanoparticles, Cobaltite Perovskite, Structural Properties, UV-Visible, Photo-Degradation
  • Mohsen Motamedi, Amirhossein Naghdi Pages 334-342

    Carbon can form numerous allotropes because of its valency. Graphene, carbon nanotubes,capped carbon nanotubes, buckyballs, and nanocones are well-known polymorphs of carbon.Remarkable mechanical properties of these carbon atoms have made them the subject of intenseresearch. Several studies have been conducted on carbon nanotubes or graphene. In the presentstudy, the molecular mechanics method was applied to model five polymorphs of carbon witha uniform approach and compare the allotropes of carbon in detail. Also, we obtained Young’smodulus and natural frequencies for every form of carbon, which can be useful for researchers.We found that an increase in the diameter of the carbon nanotube would accompany with adrop in its strength and Young’s modulus. Moreover, our results show that the capped carbonnanotube has a higher strength compared to that of the non-capped nanotube, which might bedue to the end bonds of the carbon nanotube. Finally, we identified extraordinary properties ofBuckyball including its strength, which is three times more than that of the carbon nanotubewith the same diameter

    Keywords: Graphene, Carbon nanotubes, Buckyballs, Young’s Modulus, Natural Frequencies