International Journal Of Bio-Inorganic Hybrid Nanomaterials
Volume:3 Issue: 3, Autumn 2014

The idea of smart corrosion inhibition is basis on either inhibitor consumption where it is needed or reducing harmful matrix interaction with it. In addition, applying corrosion inhibitor in a coating causes many problems such as loss of inhibition capability, coating degradation, or both. A useful technique to overcome this problem is applying of inert host systems of nanometer dimensions as nanocontainers, which is loaded by corrosion inhibitors. In the present study, mesoporous silica nanocontainers with and without inhibitor (fluoride) were dispersed in the Alkyd coatings to improve corrosion resistance of Mg metal. Then, corrosion behavior of these coatings was studied in comparison with Mg in the NaCl solution. Electrochemical tests showed that theses coatings could protect the surface from chloride solution. In addition, fluoride release from mesoporous silica nanocontainers causes MgF2 formation in the interface, as an inhibitive compound. Furthermore, the corrosion mechanism of Mg in the chloride media was attributed to the formation of MgH2 and Mg(OH)2.

This paper describes the development of a procedure for Pb(II) ions removal from various water samples after magnetic solid phase extraction (MNPs) by magnetite nanoparticles (Fe3O4 NPs) modified with sodium dodecyl sulfate (SDS) and pyrrolidine-1-dithiocarboxylic acid ammonium (PDTCAA). The synthesis of Fe3O4 NPs was certified by characterization techniques including field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier transforms infrared (FTIR) spectroscopy and vibrating-sample magnetometer (VSM) and the determination process carried out by flame atomic absorption spectrometry (FAAS). Influential parameters affecting the extraction efficiency such as pH, mass of adsorbent, and amounts of modifying agents along with desorption conditions including type, concentration and least amount of the eluent were investigated and optimized. Under the optimized experimental conditions, a dynamic linear range (DLR) of 2.5-50 μg L-1 was obtained and the limit of detection (LOD, n = 6) and relative standard deviation (RSD %, n = 3, C = 10 μg L-1) were found to be 2.5 μg L-1 and 2.2%, respectively. The developed method was applied for removal of Pb(II) ions from water samples.

In this study, we synthesized Herceptin conjugated magnetic nanoparticles (HMNs) as an alternative probe to discover the levels of HER2 (Human epidermal growth factor receptor-2) in the surface of cells. These nanoparticles can be used by magnetic resonance imaging (MRI) (non-invasive methods) for screening the patients with HER2 positive or negative tumors. Dextran coated iron oxide nanoparticles were prepared using co-precipitation method and conjugated to Herceptin antibody. The stability, cytotoxicity and HER2 specific binding of HMNs was evaluated. The HER2 expression levels of the cells were examined by measuring the signal enhancement in MRI T2 images. The core and hydrodynamic size of HMNs was 10±0.1 nm and 75±15 nm respectively. HMNs were stable up to 8 weeks in pure water and PBS buffer. The specific binding of HMNs by SKBR3, SW480, MCF7, A431 and RAJI cell lines was 19.6±2.5, 8.2±1.2, 7.3±1.3, 6.0±1.7 and 2.3±1.8 pg/cell respectively. The MRI signal enhancement of the cell lines was consistent with the specific binding results. The good characteristics of HMNs demonstrated that it can detect the HER2 levels in the cell surface and be a good candidate to use as a HER2 tracer contrast agent in MRI that needs further investigations.

Nanocrystalline complex oxides have been synthesized by combination of sol–gel auto combustion and ultrasonic irradiation techniques using copper nitrate, zinc nitrate as metallic nitrates and glycine, urea and thiourea as fuels. Sol-gel combustion (combination of the chemical sol–gel process and the combustion process) as a proper synthesized technique is used to synthesize ZnO/CuO nanocomposites. This method is based on the gelling and further combustion of solution in aqueous phase which contain salts of the desired metals and fuels. Consequently, ZnO/CuO powders were prepared with molar ratio of nitrates to fuels 1:2. Combustion process is inexpensive since it does not involve intermediate decomposition and/or calcining steps. Combustion process ends, within 30 seconds for all systems.. Finally, the product powder was characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM).

Nowadays, nanoscale innovations in the forms of pathogen detection, active packaging, antimicrobial packaging and barrier formation are poised to elevate food packaging to new heights. Antimicrobial nanocomposite LDPE films containing ZnO nanoparticles at different concentrations (e.g. 1%, 3%, 5% and 3% nano-ZnO pulse 10% polyethylene grafted maleic anhydride (PE-g-MA), w/w pure LDPE), were prepared by melt-mixing process and followed by compression molding using hot press machine. Dispersion quality of antimicrobial nanoparticle distribution within the polymer matrix has been assessed by Transmission Electron Microscopy analysis (TEM). The mechanical properties of the films prepared were characterized by using stress-strain analysis. Rheological properties of nanocomposites were determined using rotational rheometers. Rheological properties demonstrate that the rheological moduli of the nanocomposite increases with increasing the nanofiller concentration so that the high frequency region is more benefited by this effect.

TiO2/ZrO2 nanocomposite was obtained by the sonochemical technique. In this method, two separate gels containing zirconium and titanium were prepared and mixed together. The precursor sol of zirconium was prepared from an aqueous solution of ZrCl4. The precursor titanium tetra isopropoxide (TTIP) dissolved in isopropanol. Mixing of Titanium and Zirconium gels was resulted in a yellow TiO2/ZrO2 gel. The precipitate was calcinated in the furnace. The obtained nanopowder characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infra-red spectroscopy (FT-IR).

Nanostructured zinc oxide (ZnO) materials have received considerable interest from scientists due to their remarkable performance in electronics, optics and photonics. ZnO nanoparticles were synthesized by co-precipitation method. ZnO nanoparticles were synthesized using Zn(NO3)3 and K2CO3 precursors. The structure of the obtained product was confirmed by the powder X-ray diffraction (XRD) analysis. The morphology, size and structure of the as prepared ZnO nanoparticles were investigated using scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) analyses. The composition of nanocrystals was determined by electron dispersive spectroscopy (EDS). XRD pattern showed that the zinc oxide nanoparticles exhibited hexagonal wurtzite structure. By SEM images, multiple layered structure of ZnO nanoparticles were observed after calcinations. The particles size were measured in the range of 20-80 nm for sphere-like shaped as-synthesized ZnO and 40-100 nm for pyramid-like shaped annealed ZnO with less agglomeration, as estimated by XRD technique and direct HRTEM observation. The EDS spectrum showed peaks of zinc and oxygen free of impurity.

Carbon nanotubes (CNTs), nowadays, are one of the important nanomaterials that can be produce with different methods such as chemical vapor deposition (CVD). Growing of CNTs via CVD method can be influenced by several operating parameters that can affect their quality and quantity. In this article, the effects of inlet gas mixture temperature on CNT’s local growth rate, total production, and length uniformity are numerically studied in two distinct growth regimes, mass transfer controlled regime and surface reaction controlled regime, separately. Also, the effects of the interaction of inlet gas mixture temperature with furnace temperature on CNT growth are investigated.