فهرست مطالب

Nano Dimension - Volume:8 Issue: 3, Summer 2017

International Journal of Nano Dimension
Volume:8 Issue: 3, Summer 2017

  • تاریخ انتشار: 1396/05/21
  • تعداد عناوین: 10
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  • Tayseir Mohammad Abd Ellateif *, Saikat Maitra Pages 187-196
    Hydrophobic silica titanium nanoparticles (STNPs) were successfully synthesized by the sol-gel process using liquid modification. Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) studies were demonstrated the attachment of titanium on the silica surface. Titanium content enhanced the agglomeration of particles as shown in topography results. The N2 adsorption-desorption followed Type (V) isotherm indicating the meso-porous nature of the synthesized pure silica. However, STNPs followed type (II) isotherms representing the presence of the large pores. The presence of titanium reduced the surface area of silica nanoparticles with an increase in pore volume and size. Amorphous nature of the synthesized STNPs was observed using X-ray diffraction (XRD). The synthesized pure silica and STNPs exhibited considerable thermal stability up to 800 ° C. The thermo-gravimetric analysis along with the hydrophobicity test confirmed the hydrophobic nature of synthesized silica titanium nanoparticles.
    Keywords: Hydrophobicity, Mesoporosity, Silica nanoparticles, Sol-Gel, Surface modification, Titanium
  • Hadi Beitollai *, Fariba Garkani Nejad, Somayeh Tajik, Shohreh Jahani, Pourya Biparva Pages 197-205
    A novel electrochemical sensor was proposed for the determination of amitriptyline based on the copper oxide (CuO) nanoparticles modified graphite screen-printed electrode. CuO nanoparticles were used to enhance the surface area of the electrode and then improve the sensitivity of the electrochemical sensor.
    Amitriptyline electrochemical response characteristics of the modified electrode in a phosphate buffer solution (PBS) of pH 7.0 were investigated by cyclic voltammetry, differential pulse voltammetry and chronoamperometry. The linear range for the detection of amitriptyline was changed from 1.0 µM to 200.0 μM with the detection limit of 0.4 μM (S/N=3). Finally, the proposed method was applied to measure amitriptyline in real samples. It was shown that the proposed sensor exhibited significant promise as a reliable technique for the detection of amitriptyline in real samples.
    Keywords: Amitriptyline, CuO nanoparticles, Electrochemical sensor, Graphite screen-printed electrode, Voltammetry
  • Fariba Yeganeh, Rabi Behrooz *, Maryam Rahimi Pages 206-215
    Present paper examines the effect of acid type and hydrolysis conditions on morphology, size, yield and crystallinity of produced cellulose nanocrystal (CNC). Cellulose obtained from waste office paper was hydrolyzed under the same conditions by Maleic acid (MA) and Sulfuric Acid (SA) in separate treatments. Also this cellulose was hydrolyzed under different timing and temperature by MA and SA. Results showed that produced cellulose nanocrystals have different size, yield and crystallinity under same conditions by MA and SA. MA treatment resulted in higher crystallinity, yield, and disperse solution. Therefore, MA was appeared superior to SA. Based on results the characteristics of nanocrystals are not only depended on hydrolysis conditions, but also on acid type.
    Keywords: Cellulose nanocrystal (CNC), Hydrolysis, Maleic acid, Nano, Sulfuric acid
  • Muthurani Shunmugam, Hirankumar Gurusamy, Prem Anand Devarajan* Pages 216-223
    Copper oxide (CuO) nanostructures are of particular interest because of their interesting properties and promising applications in batteries, super capacitors, solar cells, gas sensors, bio sensors, nano fluids and catalysis. In Recent past, more efforts have been received to design materials with different properties which is dependent on morphology. In this work cupric oxide nano flakes were prepared by surfactant assistant wet chemical method. Samples were synthesized using ethylene glycol as the surfactant and by changing the concentration of ethylene glycol by 0 M, 0.05 M, 0.1 M, and 0.2 M. X-Ray diffraction (XRD) analysis confirmed the crystalline nature of as synthesized materials. Crystallite size and crystallographic parameters were calculated. Flakes like morphology of materials were elucidated by Scanning Electron Microscope (SEM). Using Electrochemical Impedance spectroscopy, variation of real and imaginary part of impedance, electrical conductivity with frequency and temperature were also studied. It was observed that sample with 0.1 M surfactant has high conductivity when compared to other samples. It was noted that the particle size and electrical properties of Copper oxide nano flakes were affected by concentration of the surfactant. The Conduction mechanism of Copper oxide is discussed on the basis of Correlated Barrier Hopping (CBH) model.
    Keywords: CBH model, Cupric oxide, Ethylene glycol, Impedance spectroscopy, Nano flakes
  • Rasoul Pourtaghavi Talemi *, Mohammad Hossein Mashhadizade Pages 224-233
    The glass surface modification with 3-(mercaptopropyl) trimethoxysilane (MPTS), gold nano-particles (GN) and guanine rich single strand DNA (ss-DNA) was utilized as a novel and efficient platform for sensing trace concentration of methylene blue (MB) by an inexpensive spectrophotometric method. Methylene Blue (MB) can interact with the guanine base of single strand DNA and absorbed onto glass surface and its absorbance can be determined at λmax of MB. Increase in methylene blue absorbance was linear with an increase in MB concentration and can be viewed by the naked eye and detected by spectrophotometric method. The linear range of the developed biosensor for determination of MB was from 10 to 100 nmol L-1 with a detection limit of 4 nmol L-1. The fabricated spectrophotometric MB biosensor possessed excellent selectivity and good sensitivity.
    Keywords: Glass Surface, Gold Nano-particles, Guanine, Methylene Blue, Optical DNA Biosensor, Single Strand DNA
  • Shahram Ajori *, Reza Ansari, Sina Malakpour Pages 234-240
    Successful synthesis of the stable metal-free two-dimensional polymer graphitic carbon-nitride with remarkable properties has made it as one of the most promising nanostructures in many novel nanodevices, especially photocatalytic ones. Understanding the mechanical properties of nanostructures is of crucial importance. Thus, this study employs density functional theory (DFT) to obtain the mechanical properties of graphene-like graphitic carbon-nitride (g-C3N4) nanosheets such as Young’s, bulk and shear moduli and Poisson’s ratio. Based on the results, Young’s, bulk and shear moduli of this nanosheet are lower than those of graphene and hexagonal boron-nitride sheet. Besides, it is observed that the values of the aforementioned properties for graphene-like g-C3N4 nanosheets are higher than those of porous graphene and SiC. It is further observed that the Poisson’s ratio of graphene-like g-C3N4 nanosheets is lower than those of any similar two-dimensional graphitic structures.
    Keywords: Bulk modulus, Density Functional Theory, Graphitic carbon-nitride, Shear modulus, Young's modulus
  • Navid Assi, Parviz Aberoomand Azar *, Mohammad Saber Tehrani, Seyed Waqif Husain, Maher Darwish, Sanaz Pourmand Pages 241-249
    ZnO- nanoparticles with an average particle size of 24 nm were successfully synthesized using the microwave assisted sol- gel technique. Structural and morphological properties of the nanoparticles were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy disperse spectrum (EDS) and Fourier transform infrared spectroscopy (FTIR). The band gap energy was measured to be 3.27 eV. The photocatalytic degradation of tartrazine has been studied in aqueous solution under UV-C irradiation at different pH values, catalyst doses, and tartrazine concentration. Degradation of samples was monitored by a spectrophotometer. Results have shown that 95% of 50 mg L-1 tartrazine was degraded in 120 min due to the photocatalytic degradation in presence of 0.02 g of ZnO-nanoparticles. The photocatalytic degradation kinetics has also been investigated. The experimental data were fitted very well in the pseudo-first-order kinetic and Langmuir-Hinshelwood models.
    Keywords: Degradation, Kinetics, Photocatalytic, Tartrazine, ZnO-nanoparticles, X-ray diffraction (XRD)
  • Roya Ahmadi * Pages 250-256
    In this research 1, 3, 5-triamino-2, 4, 6-trinitrobenzene (TATB) were attached with different nano structures of fullerene with 20, 24 and 60 carbons producing nano structures with diverse molecular weights. Then by the use of density functional theory methods, thermodynamic parameters of TATB with foregoing nanostructures, in wide of temperature, between 300-400 ºK were computed. To this purpose, the materials on both sides of suggested synthesis reactions were geometrically optimized, and then, the calculations of the thermodynamic parameters were performed on all of them. The values of enthalpy, Gibbs free energy and Specific heat capacity for these reactions were obtained. Also important parameters such as energy levels, the amount of HOMO/LUMO values and related parameters including electrophilicity scale, chemical hardness, chemical potential, and the maximum amount of electronic charge transferred were derived. Finally, the effect of type and molecular weight of nano structure fullerene (C20, C24, C60) on explosion properties and other chemical properties of TATB were evaluated.
    Keywords: Density Functional Theory (DFT), Enthalpy, Fullerene, TATB, Thermodynamic parameters
  • Dhananjayan Sivakumar, Mehboob Mohamed Rafi, Balaraman Sathyaseelan, Kulam Mohammed Prem Nazeer *, Ahmed Meeran Ayisha Begam Pages 257-264
    The aim of this study is to obtain polysaccharide (Glucose, Fructose and Sucrose) stabilized superparamagnetic iron oxide nanoparticles (SPIONs) by Co-Precipitation method. As prepared iron oxide nanoparticles have been characterized by X-ray Diffraction (XRD), Fourier Transform infrared (FTIR) spectroscopy, UV–Vis NIR spectroscopy, High Resolution Transmission Electron Microscope (HRTEM) and Vibrating Sample Magnetometer (VSM). The average crystallite sizes as determined from XRD for Glucose–Fe3O4 (GF), Fructose–Fe3O4 (FF) and Sucrose–Fe3O4 (SF) are 3.3, 4.82 and 5.23 nm, respectively. Powder XRD study also demonstrates that the synthesized nanoparticles are indexed for spinel cubic lattice. FTIR spectrum shows a good vibrational interaction between Fe3O4 and polysaccharides functional groups and it controls the growth of Fe3O4 nanoparticles. SPIONs exhibit superparamagnetic properties with a coercivity ranging from 0.55 to 9.13 Oe and a saturation magnetization in the range 38-42 emu/g.
    Keywords: HRTEM, Magnetic properties, Polysaccharides, SPIONs, VSM
  • Behzad Koozegar Kaleji *, Navid Alami Fariman, Navid Hosseinabadi Pages 265-273
    In this study, different samples of Niobium and Vanadium co-doped titania thin films (5-10-15 mol% Nb and 5-10-15 mol% V) were prepared via sol−gel dip coating method, using niobium chloride as niobium precursor, ammonium metavanadate as vanadium precursor, and titanium (IV) butoxide (TBT) as titanium precursor. The effects of doping amount on the structural, optical, and photo-catalytic properties of formed thin films have been studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis absorption and transmission electron microscopy (TEM). XRD patterns showed a decrease in peak intensities of the anatase crystalline phase by increasing the Nb/V dopant and doping inhibition effect on the grain growth, and revealed that all samples contained only anatase phase (T= 475 ºC). The photo-catalytic activity of the thin film was measured on degradation rate of methylene blue (MB) solution under UV irradiation. Highest photo-catalytic activity of doped TiO2 thin films were measured in the TiO2–5 mol% Nb-15 mol% V sample (TNV4). Small granular crystallites of 10-15 nm 2D diameter were observed in electron microscope micrographs.
    Keywords: Nb-V dopant, Optical properties, Sol-Gel, Thin film, TiO2