Showing 4 results for F. Khorasanizadeh
Y. Safaei-Naeini, F. Golestani-Fard, F. Khorasanizadeh, M. Aminzare, S. Zhang,
Volume 8, Issue 3 (september 2011 2011)
Abstract
Abstract:
composition of MgO and nano boehmite. The reactant and potassium chloride, as the reaction media, were fired at
800-1000 °C at different dwell times (0.5-5 h) in the ambient atmosphere. After washing and filtration, the spinel nano
powder was characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Brunauer-Emmett-
Teller (BET) techniques. It was demonstrated that the formation temperature decreased to 850
particles revealed an average size of 30 nm with a narrow size distribution. The mechanism of MgAl
was found to be a template type where the morphology and size of product were similar to those of alumina formed
from boehmite decomposition. Prolonging the reaction time from 0.5 to 3 h, the reaction was further completed and
crystallinity was improved. However, the increase of temperature was more effective in this regard.
MgAl2O4 (MA) nano powder was synthesized via molten salt technique, by heating stochiometric°C. The nano spinel2O4 formation
Y. Safaei-Naeini, M. Aminzare, F. Golestani-Fard, F. Khorasanizadeh, E. Salahi,
Volume 9, Issue 1 (march 2012 2012)
Abstract
Ultraviolet–Visible (UV–Vis) spectroscopy was used, in the current investigation, to explore the dispersion and stability of titania nanoparticles in an aqueous media with different types of dispersants. Hydrochloric and nitric acids as well as ammonia were used to determine the stability of the suspension in the acidic region (pH=2.5) and basic area (pH=9.5), respectively. In addition, for measuring sustainability of suspension and creating steric, and electrosteric repulsive forces, ethylene glycol and ethylene glycol plus ammonia were employed, respectively. UV–V is
spectrometry was applied to realize the effect of nano titania concentrations and different types of dispersants of samples containing different amounts of nano titania and different types of dispersants on stability of TiO2-containing suspensions. In addition, the stability of dispersion could be evaluated in colloidal mixtures containing ethylene glycol plus ammonia. It was demonstrated that the mixtures containing ethylene glycol plus ammonia were stable over a period of 4 days. To support the UV–Vis results, other techniques such as atomic force microscopy (AFM) and scanning electron microscopy (SEM) were employed to study the degree of agglomeration of titania nanoparticles in terms ofmorphology and size.
S. Safi, R. Yazdani Rad, A. Kazemzade, Y. Safaei Naeini, F. Khorasanizadeh,
Volume 9, Issue 2 (june 2012 2012)
Abstract
C-SiC composites with carbon-based mesocarbon microbeads (MCMB) preforms are new type of highpreformance and high-temperature structural materials for aerospace applications. In this study MCMB-SiC composites with high density (2.41 g.cm-3) and high bending strength (210 MPa,) was prepared by cold isostatic press of mixed mesophase carbon powder derived from mesophase pitch with different amount (0, 2.5, 5%) nano SiC particles. All samples were carbonized under graphite bed until 1000 °C and finally liquid silicon infiltration (LSI). Microstructure observations resultant samples were performed by scanning electron microscopy and transition electron microscopy (SEM & TEM). Density, porosity and bending strength of final samples were also measured and calculated. Results indicates that the density of samples with nano additive increased significantly in compare to the free nano additives samples.
F. Khorasanizadeh, B. Eftekhari Yekta, Y. Safaei-Naeini,
Volume 10, Issue 1 (march 2013)
Abstract
Abstract:Some types of glass and glass ceramics have a great potential for making bone tissue engineering scaffolds, drug carrier and bone cements as they can bond to host bone, stimulate bone cells toward osteogenesis, and resorb at the same time as the bone is repaired. Calcium phosphate glass ceramics have very attractive properties that allow them to use in bone tissue engineering. Calcium phosphate glasses could be used for the fabrication of resorbable constructs, with controlled biodegradability. This work was investigated crystallization and sinterability of biodegradable glass ceramics in the CaO–P2O5–Na2O–TiO2 system using differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Sinterability of the glasses also was investigated by measurement of sintering parameters. Different thermal treatments were applied to control the degree of devitrification of glasses. In the developed glass ceramics Ca2P2O7 were the first phase to precipitate in the mother glass structure, followed by Ca(PO3)2 and TiP2O7 at elevated temperature. Ca2P2O7 and Ca(PO3)2 seem to have a very positive effect in bone formation in vivo. It is therefore expected that glass ceramics understudy have good potential to be used for bone regeneration applications
