فهرست مطالب

Nanoscience and Nanotechnology - Volume:14 Issue:2, 2018
  • Volume:14 Issue:2, 2018
  • تاریخ انتشار: 1397/04/03
  • تعداد عناوین: 9
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  • R. Ahmadi *, A. Razaghian, Z. Eivazi, K. Shahidi Pages 93-99
    We report an investigation on the synthesis of Copper Oxide nanostructures via the Electro-Explosion of Wire method. Cu-CuO and Cu-Cu2O nanoparticles with mean particle size of 21.1 to 59.1 nm were synthesized by changing the applied current density and amount of used Tetra Methyl Ammonium Hydroxide as the surfactant. The X-ray diffraction analysis, field emission scanning electron microscopy and Fourier transform infrared spectroscopy techniques have been used for characterization of the prepared samples. The results confirmed the influence of surfactant application on the size, morphology and chemical composition of the synthesized nanoparticles, while the applied current density has only had a significant effect on the mean particle size.
    Keywords: Electro-explosion of wire, Copper oxide, Nanoparticle, Tetra methyl ammonium hydroxide, Field emission microscopy
  • M. H. Ghajar *, M. Mousavi, S. Burzhuev, M. Irannejad, M. Yavuz, E. Abdel-Rahman Pages 101-109
    Micro-electroactive polymers have wide applications from industry to healthcare. Artificial muscles, microvalves, microswitches, haptic sensing, blood pressure and pulse monitoring are some potential applications for micro-electroactive polymers. The most advantage of micro-electroactive polymers as sensors and actuators is bio-compatibility and low power threshold for large deformations. In this short review, some applicable fabrication methods of micro-electroactive polymer cantilever are reviewed. Furthermore, a novel method based on standard micro fabrication techniques is designed and discussed in details which presents a conceptual design of a micro-electroactive polymer cantilever on a polymeric anchor located on a silicon substrate for future works.
    Keywords: Micro fabrication, Electroactive polymer, Cantilever
  • S. Pal, S. Mondal, J. Maity *, R. Mukherjee Pages 111-119
    In this paper, we report the synthesis of ZnO nanoparticles using Moringa Oleifera (Drumstick) leaves as natural precursor via precipitation method. Formation and characterization of ZnO nanoparticles was established by UV-VIS spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. The synthesized nanoparticles have hexagonal wurtzite structure of an average grain size of 52 nm confirmed from X-ray diffraction analysis. The synthesized ZnO nanoparticles have been employed as photocatalytic agent to degrade the organic dye viz. Titan yellow under visible light by exposing the visible light for one hour. ZnO nanoparticles degraded almost 96% of titan yellow dye. We also studied the antibacterial activity and it was found that the synthesized ZnO nanoparticles have potential applications in antibacterial activity. For antibacterial studies we used Bacillus subtilis as a gram positive and Escherichia coli as gram negative bacteria.
    Keywords: ZnO nanoparticles, Photocatalytic degradation, Antibacterial activity
  • R. Marani, A. G. Perri * Pages 121-131
    In this paper we implement a simple DC model for CNTFETs already proposed by us in order to carry out static analysis of basic digital circuits. To verify the validity of the obtained results, they are compared with those of Wong model, resulting in good agreement, but obtaining a lighter ensuring compile and shorter execution time, which are the main characteristics to have an easy implementation in circuit simulators for CAD applications.
    Keywords: CNTFET, Digital design, Static analysis
  • S. M. Mousavi Kouhi *, M. Lahouti Pages 133-141
    Present study has comparatively investigated the effect of zinc oxide nanoparticles (ZnO NPs), ZnO bulk particles (BPs), and relevant metal ions (Zn2) on the tissue culture of rapeseed (Brassica napus L.) to properly evaluate the impact of ZnO NPs on callus induction. For finding the best hormonal combination for inducing callus, hypocotyl explants were cultured on Murashige and Skoog (MS) media containing different combinations of plant growth regulators. After that, hypocotyl explants were cultured in MS media containing the best hormonal combination, supplemented with four different concentrations (10, 25, 50, 100 mg L-1) of ZnO NPs, ZnO BPs, or equivalent concentrations of Zn2. Results showed that 10 mg L-1 ZnO NPs can induce callus and shoot regeneration, while the same concentrations of other treatments cannot. Callus growth was significantly retarded by 25, 50 and 100 mg L-1 of all three types of treatment in a dose-dependent manner. Under highest concentration of ZnO NPs, callus was not induced. It can be concluded that optimum concentration of ZnO NPs can be beneficial for inducing callus and/or shoot regeneration in the plant tissue culture.
    Keywords: Brassica napus, Callus, Shoot regeneration, ZnO nanoparticles
  • M. Yeganeh *, S. M. Marashi, N. Mohammadi Pages 143-151
    In this research, mesoporous silica was served as the host of molybdate (corrosion inhibitor). The loaded mesoporous silica was dispersed in a paint matrix. The composite was then coated on the carbon steel surface. Polarization and electrochemical impedance spectroscopy (EIS) tests showed that the corrosion resistance of the scratched paint containing molybdate loaded mesoporous silica was better than the one without it or neat paint at near neutral pH. Charge transfer resistance regarding inhibitor loaded mesoporous silica showed a higher value in comparison with unloaded one. This parameter for the coating with inhibitor loaded mesoporous silica at the higher pH recorded 589300 Ω.cm2, while it was 209100 Ω.cm2 for un-loaded mesoporous silica. On the other hand, scanning electron microscopy (SEM) studies showed the release of corrosion inhibitor in the scratch zone which was due to the pH-sensitive release of corrosion inhibitor in the corrosive media.
    Keywords: Mesoporous silica, Molybdate, Corrosion inhibitor, Release, Smart corrosion protection
  • H. Akherat Doost, M. H. Majles Ara *, E. Koushki Pages 153-158
    This article describes a study, using numerical simulation, of the optical properties of nano particles as a function of their size. Many methods introduced to simulate and calculate the interaction of light and particle, such as Mie analysis, boundary element and finite element methods. The Discrete Dipole Approximation (DDA), wherein a target geometry is modeled as a finite array of polarizable elements and DDSCAT simulation, are employed for determining extinction, absorption and scattering cross sections by gold nano particles with 15, 35, 55, 75, 100, 125 and 150 nanometers in diameter in different wavelengths. In this method, the particle is represented as a cubic array of electric dipoles. The results show that Plasmon resonance dependent on nano particles size. In other project, the angular distribution of different sizes of gold nano particles are calculated and scattering of these particles are compared. This study can be helpful in designing appropriately shaped nano particles for in-vivo applications like photo-thermal cancer treatment and optical sensors.
    Keywords: Absorption, scattering of gold nanoparticles, Discrete Dipole Approximation (DDA), DDSCAT simulation
  • A. Anaraki Firooz * Pages 159-163
    Mo-doped SnO2 nanoparticles were prepared using hydrothermal method. The average grain size obtained by varying calcinations temperature from 160 to 500 oC showed the different sizes. Prepared materials characterized by X-Ray diffraction (XRD) and scanning electron microscopy (SEM). Also the FTIR and the UV–Vis absorptive spectra have been carried out. Mo- doped SnO2 nanoparticles with different sizes used as a catalyst for epoxidation of cycloocten. The result revealed that the existence of Mo species caused an increasing sensitivity on epoxidation.
    Keywords: Mo doped, SnO2, Nanoparticle, Hydrothermal, Epoxidation
  • J. Azamat* Pages 165-175
    Graphene oxide nanosheet (GONS) can be a suitable membrane for gas separation with high permeability and selectivity. Separation of N2/CO2 using functionalized GONS was investigated by molecular dynamics simulations. The simulated systems were comprised of two types of GONS with a pore in their center, N2 and CO2 molecules. The selectivity and permeability of these molecules can be controlled by drilling various pores with different sizes and functionalized factors in the edge of pores of GONS. Modification of pores using attaching functional groups to the carbon atoms at the edge of pores leads to very different outcomes. Using hydroxyl group at the edge of GONS pore (pore 1) leads to a substantial increase in the selectivity for N2 over CO2 and using fluoride atoms at the edge of GONS pore (pore 2) actually inverts the selectivity. When the pore size further increases, selective separation of molecules does not happen and both molecules propagate through the pores. Due to the interactions between molecules and membrane pores, the energy barrier for gas molecules in two pores was different, so that, the low energy barrier was in the pore 1 for N2 and in the pore 2 for CO2 molecules. If the energy barrier difference between two types of molecules is high, complete separation occurs. The present research is valuable for designing the novel GONS membranes for gas separation.
    Keywords: Graphene oxide nanosheet, Gas separation, PMF