فهرست مطالب

Nano Dimension - Volume:7 Issue: 2, Spring 2016

International Journal of Nano Dimension
Volume:7 Issue: 2, Spring 2016

  • تاریخ انتشار: 1395/04/02
  • تعداد عناوین: 10
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  • H. Ahmad*, K. Rajagopal, A. Hussain Pages 97-108
    Silver nanoparticles (AgNPs) are amongst the most investigated materials in nanotechnology in view of their unique physio-chemical features and applications in restorative science. Their progressive usages in different fields of science besides some predominant restrictions with conventional methods for their synthesis have demanded analysts to discover green courses for their creation. Biological methods are the preferred to combat with the issues concerned with the nanoparticle synthesis. Within this decade, thousands of plants have been screened to analyze their final impact on characterization and morphology of AgNPs compared to general approach of their synthesis. Phytosynthetic method is an eco-friendly route that can lead to an advanced production of silver nanoparticles with controlled morphology. We herein reviewed the present aspects of phytosynthesis of AgNPs and their importance in modern science. Moreover, overviews of proposed mechanisms in this technology have also been included, which ultimately provide some insights of their safe use and demand for further research.
    Keywords: Ecofriendly, Green synthesis, Nanotechnology, Nanomaterials, Phytosynthsesis, Plant extract, Silver Nanoparticles
  • H. Sadegh*, R. Shahryari, Ghoshekandi, A. Masjedi, Z. Mahmoodi, M. Kazemi Pages 109-120
    Carbon nanotubes (CNTs) are a novel material that exhibits good adsorption behavior toward various toxic pollutants in aqueous solution. These adsorbents have a fast adsorption rate and high adsorption efficiency, efficient to remove various pollutants and they are easy to recover and reuse. These features highlight the suitability of CNTs for the treatment of water polluted with heavy metal ions and dyes. This review outlines the preparation of CNTs as well as different methods of surface modification of these materials by non-covalent and covalent functionalization strategies. Additionally, an overview of recent developments and applications of CNTs for heavy metal ions and dyes pollutant removal is discussed in detail. Based on current research and existing materials, some new and futuristic approaches in this fascinating area are also discussed. The main objective of this review is to provide up-to-date information about the most important features of CNTs and to show their advantages as adsorbents in the treatment of polluted aqueous solutions.
    Keywords: Adsorption, Carbon nanotubes, Dyes, Heavy metal ions, Pollutant Removal
  • A. Pourahmad* Pages 121-126
    Molecular sieves MCM-41 were synthesized from rice husk ash (RHA) as alternative sources of silica. The material was synthesized by a room temperature method from a gel with the molar composition SiO2: 1.6EA: 0.215HDTMABr: 325H2O with pH correction. The cetyltrimethylammonium bromide (CTMABr) was used as a structure template. Nanocomposite containing 5.0 and 10.0 wt.% of Cu was synthesized under solid state reaction. The calcinations of samples were done at two different temperatures, 400 and 600◦C. The morphology and the physicochemical properties of the prepared samples were investigated by X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). TEM images indicated that nanoparticles size of CuO is ~ 3 nm.
    Keywords: Green chemistry, Nanocatalyst, Nanocomposite, Semiconductor, TEM
  • Z. Tohidian, I. Sheikhshoaie*, M. Khaleghi Pages 127-136
    New two nano- sized Schiff base complexes [M(L)], where L= 2, 2'-((1E, 1E')-(1, 2 phenylen bis (azanylylidene)) bis (methanylylidene)) bis (4-bromo phenolato) and M=Cu or Zn, (a, b complexes) were synthesized by ultrasonic irradiation. These complexes were characterized by elemental analysis, molar conductivity, FT-IR, fluorescence emission, 1H NMR, field emission scanning electron spectroscopy (FESEM) and UV-Vis spectroscopy. The UV-Vis spectroscopic data and fluorescence emission bands of these nano-sized Schiff base complexes show a shift in comparison with the bulk sample analogue, due to the reduction in particle size to nano scale. In vitro antimicrobial activities of the title compounds against some Gram-positive (Staphylococcus aureus, Micrococcus luteus, Bacillus cereus, Eterococcus faecalis) and Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella sp, Pscudomonas sp) and fungus strain (Candida albicans) were investigated and compared with each other. It was found that Cu (II) complex showed higher ant
    Keywords: Antimicrobial effect, FESEM, Fluorescence emission, Nano scale, Schiff base complex
  • K. Kaur, R. Komal* Pages 137-143
    In the present study, we have reported the biological synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract prepared by hot percolation treatment of wheat varities (PBW343, Triticum durum and Aegilops tauschii )for the reduction of silver ions to silver nanoparticles. Bioreduction of Ag to Ag0 was observed when aqueous extract augmented with silver nitrate (AgNO3) was incubated for 2 hours at 1000C. The formation of silver nanoparticles was confirmed by surface plasmon resonance as determined by UV-Vis spectra at 430 nm. Silver nanoparticles of size ranging from 5-14 nm of spherical shape were characterized using transmission electron microscopy (TEM). These nanoparticles were found to possess potential antibacterial activity against (Escherichia coli, Staphylococcus aureus, Klebsiella) using disc diffusion method and macro dilution(tube)broth method. This environmental friendly method provides a simple, easy, fast and cost effective method for nanoparticles synthesis and can be used in several areas of medicines and industries.
    Keywords: A. Tauschii, Antibacterial, Macrodilution (Tube) broth method, Silver Nanoparticles, T. Durum, TEM (Transmission Electron Microscopy), Wheat varieties (PBW343)
  • S. Tahmasebi, O. Moradi*, M. Yari Pages 144-149
    In this research, Graphene Oxide- Gold nanoparticles (AuNP/GO) were easily fabricated by a redox reaction between GO and chloroauric acid without using any additional reductant and then used to stabilize Pickering emulsions. (AuNP/GO) was investigated by FT-IR spectroscopy. The changes of parameters such as contact time, pH, Amoxicillin initial concentration and temperature were tested and investigated by several adsorption experiments various factors affecting the uptake behavior such as initial concentration, contact time and temperature were studied. The adsorption kinetics well described by a pseudo-second-order rate model. The adsorption kinetics well described by a pseudo-second-order rate model.The adsorption kinetics well described by a pseudo-second-order rate model.
    Keywords: Adsorption, Amoxicillin, Chloroauric acid, Gold nanoparticles, Graphene Oxide, Kinetics parameters
  • A. Tadjarodi*, M. Imani Pages 150-159
    In this work, the synthesis of porous structure of cadmium oxide with multilayered sheet-like morphology in nano-meter size using adipic acid as soft template by solvothermal/thermal decomposition process is reported. Chemical analyses exhibited that the formation of porous sheet-like structure is originated from bidentate coordination mode of adipate units to Cd-center. It was found that the change of reaction conditions can vary final morphology of product due to the different coordination modes of adipate units. The structural and morphological characterizations of product were discussed in detail. Brunauer-Emmett-Teller (BET) analysis indicated a specific surface area of 52.08 m2g-1 with pore size distribution centered at 11.7 nm for prepared CdO sheet-like nanostructure. The capability of the as prepared product for adsorption of dye pollutants from aqueous solution was also studied. The results showed a maximum adsorption capacity (qmax) of 500 mg g−1 for adsorption of Congo Red (CR) dye in water revealing a superior ability of this product for adsorption of dye pollutants.
    Keywords: Adsorption, CdO, Nanostructure, Soft template, Solvothermal process
  • A. Shokri* Pages 160-167
    In this project, a nano catalyst (TiO2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4NP) from industrial wastewater. The effect of some operational parameters such as initial pH (3-9), the concentration of pollutant (20-80 mg/L), and amount of TiO2 were investigated. In O3/TiO2 process, the anion radical ( was formed before the production of hydroxyl radical. These results were different from the Ozonation process alone, in which high pH had a positive effect on the degradation of 4NP, because hydroxyl radicals was formed. In ozonation and O3/TiO2 processes, about 89 and 97% of 4NP were degraded respectively, at optimum pH and 60 min of reaction. In catalytic ozonation the degradation rate of 4NP was higher at weak acidic pH conditions (pH=5). The removal of chemical oxygen demand (COD) was increased from 49% (only ozonation) to 74% (O3/TiO2) at 90 min of reaction. The kinetic of degradation was pseudo-first-order and degradation and mineralization of 4NP were estimated by HPLC and COD tests, respectively.
    Keywords: Chemical Oxygen demand (COD), Degradation, Petrochemical wastewater, TiO2 nano catalyst, 2, Nitrophenol (2NP)
  • P. N. Dave*, P. N. Ram, Sh. Chaturvedi Pages 168-173
    Composite solid propellants were prepared with and without nano-alloys (Ti-Co, Ti-Ni, Ti-Zn), where nano-alloys used as catalyst. These nano-alloys are prepared by hydrazine reduction method. Catalytic properties of these nanomaterials were measured on Ammonium perchorate/hydroxyterminatedpolybutadiene propellant by thermogravimetery analysis and differential thermal analysis. Both experimental results show enhance in the thermal decomposition of propellants in presence of nano-alloys. In this differential thermal analysis method experiments had done in 3 heating rate â1=5, â2=10, â3=15 degree on minute. Independent to model free; calculation of activation energy of high temperature decomposition step was done by using following kissinger equation. Burning rate of propellants is also calculated.
    Keywords: Activation energy, Ammonium perchlorate, Burning rate, Propellants, Thermal decomposition
  • M. Mohammadi Zeydi*, N. O. Mahmoodi Pages 174-179
    An efficient, simple and convenient route is described for the synthesis of biscoumarin (3,3'-(arylmethylene) bis (4-hydroxy-2H-chromen-2-one)) by using of recyclable catalyst TiO2@KSF. In this Method, we synthesis biscoumarin derivatives via 3multi-component reactions (3MCRs) of two equivalent 4-hydroxycoumarin with one equivalent of aromatic aldehydes using 20 mg nano TiO2@KSF as homogeneous catalyst under solvent-free conditions at 60 °C for the required reaction times (8–15 min). The advantages of this protocol in synthesis of biscoumarin derivatives as an solvent-free condition, using rather inexpensive catalyst, commercially available starting materials, reusability of TiO2@KSF, simple work-up due to solid phase, high yields and short reaction times. The catalyst can be recovered and reused for four times without much loss in reactivity. The structure of all biscoumarin derivatives was confirmed by FT-IR, 1H NMR spectra and compared with reliable references.
    Keywords: Aromatic aldehydes, Biscoumarins, Nano TiO2@KSF, Solvent, free conditions, 4, Hydroxycoumarin