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Nano Dimension - Volume:4 Issue: 2, Autumn 2013

International Journal of Nano Dimension
Volume:4 Issue: 2, Autumn 2013

  • تاریخ انتشار: 1392/01/18
  • تعداد عناوین: 11
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  • Sh. Sohrabnezhad *, A. Habibi, Yangjeh, S. Eftekhari Page 91
    AlMCM-41 was applied for adsorption of methylene blue (MB) and auramine (AU) in single and binary component systems. In the single component systems, AlMCM-41 represents higher adsorption capacity for MB than AU with the maximal adsorption capacity of 2.07×10−4 and 1.15×10−4 mol/g at 25 ˚C for MB and AU, respectively. In the binary component system, MB and AU exhibit competitive adsorption onto the adsorbent. In single and binary component systems, kinetic and adsorption isotherm studies demonstrate that the data are following pseudo-second-order kinetic model and Langmuir isotherm. Also, in both cases, kinetic data is fairly described by two-step diffusion model. Effect of solution pH on the adsorption of MB and AU in single and binary component systems was studied and the results were described by electrostatic interactions.
    Keywords: Competitive adsorption, Nanodimensional AlMCM, 41, Adsorption kinetic, Adsorption isotherm, Methylene blue, Auramine
  • Kalpana Kanchan, Sharmita Gupta, G.P.Satsangi, J.N. Shrivastava Page 105
    Interaction of Chrysosporium sps. and Aspergillus sps. with aqueous AgNO3 was investigated for synthesis of silver nanoparticles. Biological reduction and extracellular synthesis of silver nanoparticles in 28 hour at 270C and pH 5.6 was done. The nanometallic dispersion was characterized by surface plasmon absorbance measuring at 424 – 530 nm for Ag nanoparticles. High resolution transmission electron microscopy showed the formation of silver nanoparticles in magnification of 50-100 nm. XRD analysis of the silver nanoparticles confirmed the formation of silver nanoparticles at average size of 29.18 nm.
    Keywords: Silver Nanoparticles, Biosynthesis, Chrysosporium, Aspergillus, Surface plasmon absorbance
  • A. Bagheri G., V. Ashayeri, K. Mahanpoor Page 111
    In this paper CuFe2O4, nanocrystalline powders were prepared. Also, the supported Cu ferrite was obtained by impregnation of the supports with Cu and Fe nitrates solutions, for calcination temperature 450 ºC. The samples were characterized by X-ray powder diffraction (XRD) and Fourier transform-infrared spectroscopy (FT-IR). In this investigation photocatalytic degradation of Acid red 206 in water was studied. The results show that the CuFe2O4 is an active photocatalyst. A first order reaction with k = 0.123 min-1 was observed. The effects of some parameters such as pH, amount of photocatalyst, initial concentration of dye were examined.
    Keywords: Photodegradation, Photocatalysts, CuFe2O4, Acid Red 206, Adsorption
  • El, Sharkawy H. A Page 117
    This article describes an accurate subPico flowmeter bifurcatedin to liquid and gas flowrates less than 1mol/s for both MEMS/NEMS and cryogenic technology applications. The MEMS/NEMS are described as either two Gauges (instrument), or quartz fluctuating forks, even if the liquid or gas flows through an element, as well as cryogenic technology consisting of arrays of either parallel photonic crystal micelles or parallel rectangular nano-channels by using the lithography and anodic bonding techniques on silicon micelles. The behavior of gas or liquid Helium at high pressure was found to differ from the prediction of the conventional Heigen Equation. A hydro-dynamic model showed a gas or liquid properties namely molar flow rate, input and output pressure, two pressure gauges or quartz fluctuating (Todd Helmenstine) forksand the temperature. The measurements with fluid Helium demonstrated that the flow cells could span the flow range from 10-15 to 10-12 mol/s. This paper had focused on a versatile method of creating wide area defect free crystals based on interference lithography (MEMS/NEMS and cryostat). This technique involves splitting a monochromatic plane wave from a laser into multiple beams and recombining them inside a photoresist (fluid compressibility).
    Keywords: Nano, Flow, MacroScale Channels, Surface Effects, Navier, Stokes Equations, Super, Hydrophobicity
  • J. E. Jam, A. T. Samaei Page 131
    In this paper, the modified Euler-Bernoulli beam model is presented to examine the influence of surface elasticity and residual surface tension on the critical force of axial buckling of nanotubes in the presence of rotary inertia. An explicit solution is derived for the buckling loads of microscaled Euler beams considering surface effects. The size-dependent buckling behavior of the nanotube due to surface effects is well elucidated in the obtained solutions. The critical forces are evaluated for axial buckling of cantilever beams. The results are compared with those corresponding to the classical beam model. The influences of the surface effects on the critical forces are discussed in detail.
    Keywords: Nanotubes, Nanowire, Surface effect, Buckling, Euler, Bernoulli beam model
  • Jyotiranjan Roul, Sunit Kumar Sahoo, Ranjit Mohapatra, Nitin Tribhuvan, Nanasaheb B. Dharbale Page 135
    This paper discusses about preparation of biodegradable polymer /clay nanocomposites based on organically modified montmorillonite clay; i.e. cloisite 10A and biodegradable polymer chitosan by solution mixing technique and their characterization. The nanocomposites were successfully prepared and their structures were characterized by powder x-ray diffraction (XRD), particle size analyzer (Beckman coulter), scanning electron microscopy (SEM), and fourier transmission infra red spectroscopy (FT-IR) techniques. The intensity distributions and average size and polydispersity index of particles were confirmed from particle size analysis. The XRD results revealed the information on the degree of hybrid structure generated and crystal size. The surface topography of polymer nanocomposites and their shapes were determined from SEM. These SEM results confirmed the exfoliation of polymer between the clay layers. From both XRD and particle size analysis results, it is revealed that the average diameters of the prepared nanocomposites were found to be within 300-500nm. So these nanoformulations are expected to be beneficial for controlled drug delivery system.
    Keywords: Chitosan, Cloisite 10A, Nanocomposite, Biodegradable polymers, XRD
  • Azar Haghighi Poshtiri, Hamid Reza Taghiyari, Ali Naghi Karimi Page 141
    Fire-retarding properties of wollastonite nanofibers in poplar wood (Populus nigra) were studied here. Some physical properties such as water absorption, volumetric swelling and anti-swelling efficiency (ASE) were also measured. Specimens were prepared according to the ISO 11925 specifications for the fire-retarding properties and according to the ASTM D4446 -2002 specifications for the physical properties. Impregnation of wood specimens with nanowollastonite was carried out at consumption levels of 4, 6.3, 10 and 12%, using Rueping Method (empty-cell process) and compared with the control specimens. Five fire-retarding properties were measured, including weight loss (%), ignition point (s), fire endurance (s), glow endurance (s) and carbonization area (%). The obtained results indicated that fire-retarding properties were significantly improved in the NW-treated specimens. Furthermore, the NW-impregnated specimens gained higher dimensional stability. However, water absorption increased. Heat-conductivity of wollastonite limited accumulation of heat at one spot, furthermore, it acted as a physical barrier to deter heat and mass transfer between the gas and the condensed phase, consequently, fire-retarding properties were improved.
    Keywords: Poplar wood, Minerals, Nano, wollastonite, Rueping method, Fire, retarding properties, Water absorption, Anti, swelling efficiency
  • Subramanian Ravichandran Page 153
    Zinc oxide nanoparticles have been synthesized by chemical reaction method. Polyvinyl alcohol (PVA) composite film filled with nanometric, monodispersed zinc oxide nano particles prepared by PVA solution and nanozinc oxide. Polymer blend with ZnO nanoparticle composite film has prepared by casting technique. The property of nano composites depends greatly on the chemistry of polymer matrices. The dispersion of nano particles in the polymer matrices is a general prerequisite for achieving desired mechanical and physical properties. Particular attention is paid on the structural and mechanical properties of a composite film by SEM and Measurement of tensile properties. The results also shows that, the ZnO NPs were uniformly dispersed in the polymer matrix and the particles remained their original size (20-150 nm) before incorporate in to the polymer matrix.
    Keywords: Zinc Oxide nano particles, Polyvinylalcohol, Polyvinylpyrrolidone, Composite film, SEM, stress, Strain measurements
  • N.Molahasani, M.S.Sadjadi, K.Zare Page 161
    Nanocrystalline Zinc Oxide (ZnO) powders with different morphology have been successfully synthesized by using different surfactants such as Cetyl Trimethyl Ammonium Bromide (CTAB), Sodium Dodecyl Sulphate (SDS), and Tri Ethanol Amine (TEA) via hydrothermal method. The products were characterized by means of powder X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV-visible absorption and Photoluminescence (PL) spectroscopy. The sheets, rods, and spherical morphologies of the prepared SDS, CTAB, and TEA mediated ZnO were observed in the SEM micrographs.
    Keywords: Zinc Oxide (ZnO), Surfactant, Photoluminescence, Hydrothermal method, Transmission Electron Microscopy (TEM)
  • Qian Wang, Ren, Feng Mao Page 167
    Nanotechnology has been advanced since the last decades. Among all nanomaterials that have been developed, nanosilver is the most frequently used nanoparticles. Its release into natural water bodies is inevitable due to its broad applications. Nanosilver (nAg) was prepared via Tollens method using. The morphology, size distribution and average size of the obtained nAg was characterized using Transmission electron microscope (TEM) and Dynamic light scattering (DLS) technique. Stability of nanosilver was determined using UV-Vis spectroscopic method. Additionally, a time-resolved DLS technique was applied to confirm the UV-Vis spectroscopic results
    Keywords: Nanosilver, Natural water, Tollens method, Transmission Electron Microscope (TEM), UV, Vis spectroscopy
  • A.Rostami, Sh.Andalibi, S.K.Seyyedi.S., S.Zabihi Page 171
    In this study, for increasing absorption of the active layer in bulk hetero junction (BHJ) organic solar cells (OSCs) we used surface Plasmon effects of metal nano particles (MNPs). We embedded the MNPs inside the active layer and studied the device structure. For shown the results we investigated the model of our structure with Finite Difference Time Domain (FDTD) numerical method and achieved electromagnetic field characters. From the result of this model, drown absorption curve that obviously shown enhancement in light absorption and thus the improving in power convertion efficiency (PCE).
    Keywords: Light absorption, Organic solar cells, Metal nano particle, Surface plasmon, Power Convertion Efficiency (PCE)