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Structural properties of nickel doped cobalt ferrite were synthesized by co-precipitation method with sodium dodecyl sulfate (SDS) as a surfactant at different temperatures. The particle size was estimated by the full width half maximum (FWHM) of the strongest X-ray diffraction (XRD) peak. The average particle size was in the range of 21-36 nm. The particles size was controlled via controlling calcination temperature which was in the range of 600 to 900°C. The morphology of nickel doped cobalt ferrite was investigated. The results showed that a well crystalline single cubic structure of nickel doped CoFe2O4 phase was formed through precipitation precursors at pH value of 11. The pH was adjusted by the use of ammonium hydroxide solution. [ABSTRACT FROM AUTHOR]

Anionic clay Mg-Al Layered double hydroxide (Mg-Al LDHs) of Mg/Al-NO3- with M2+:M3+ (3:1) ratio was synthesized by co-precipitation method from nitrate salt solutions were used with continuous agitation at constant pH 9. Beside, modification of nitrate anions by stearate anions between the LDH layers had carried out through ion exchange reaction. Polyhydroxybutyrate (PHB)/Polycaprolactone (PCL)/stearate Mg-Al Layered Double Hydroxide (LDH) nanocomposites were prepared via solution casting intercalation method. FT-IR spectra showed the presence of carboxylic acid (COOH) group indicates that stearate anions were successfully replacing the nitrate anions in the interlayer Mg-Al LDH. The XRD results showed that increasing basal spacing from 8.66 to 32.97 Å in modified stearate Mg-Al LDH. Additional of 1.0 wt % stearate Mg-Al LDH resulting higher basal spacing where polymer chain intercalated into interlayer LDH and TEM results revealed that the 1.0 wt % stearate Mg-Al LDH layers are homogeneously distributed in the PHB/PCL polymer blends matrix. TGA characterization proven that 80PHB/20PCL/1stearate Mg-Al LDH has lower weight loss and higher thermal stability. Enhancement in 300% elongation at break and 66% tensile strength in the presence of 1.0 wt % of the stearate Mg-Al LDH as compare with PHB/PCL blends. Scanning electron microscopy (SEM) proved that clay improves compatibility between polymer matrix and the best ratio 80PHB/20PCL/1stearate Mg-Al LDH surface was well dispersed and stretched before it breaks. [ABSTRACT FROM AUTHOR]

Poly-3-hydroxybutyrate/Poly(butyleneadipate-co-terephthalate)/layered double hydroxide (PHB/PBAT/LDH) nanocomposites were prepared from PHB/PBAT blend and stearate Zn3Al LDH via a solution casting method in this study. By using co-precipitation method, the pristine Zn3Al LDH was prepared from nitrate salts solution at pH 7 and then modified by stearate anions through an ion exchange reaction. This modification increased the basal spacing of the LDH from 8.77 to 24.94 Å. The stearate Zn3Al LDH infrared spectrum showed the presence of stearate ions in the synthesized Zn3Al LDH. Mechanical properties of the nanocomposites with 2 wt% stearate Zn3Al LDH content show 56 wt% improvements in elongation at break compared to those of the blend. [ABSTRACT FROM AUTHOR]

The artificial neural network (ANN) models have the capacity to eliminate the need for expensive experimental investigation in various areas of manufacturing processes, including the casting methods. Determination of particle size is one of the critical parameters in nanotechnology.TheAg-NPs have attracted significant attention for chemical, physical and clinical applications due to their exceptional properties.The nanosilver crystals were prepared in the biopolymer mediated without any aggregation by using green chemical reduction method. The method has an advantage of size control which is essential in nano-metal synthesis. The resulting of silver nanoparticles (Ag-NPs) characterized by using of X-ray diffraction (XRD) and transmission electron microscopy (TEM) technique.XRD patterns confirmed that Ag-NPs crystallographic planes were face centered cubic (fcc) type. TEM results showed that mean diameters of Ag-NPs for four different amounts of variables were less than 40 nm. This method with comparison to other methods is green, high yield, speedy and easy to use.This paper presents an ANN model for the predictionsize of Ag-NPs by green method. Themodel accounts for the effect of NaOH volumes, temperature, stabilizer, and AgNO3 concentration on the size of nanoparticle.The best model presented a trustworthy agreement in predicting experimental data. The characteristic parameters of the presented ANN models are fully reported in the paper. [ABSTRACT FROM AUTHOR]

A green quick precipitation method was successfully used for synthesis of magnetic iron oxide nanoparticles (Fe3O4-NPs) on the surface of sodium/potassium type zeolite. Ferric chloride, ferrous chloride and sodium hydroxide aqueous solutions were used in the synthesis and coating of the Fe3O4-NPs on the surface of the zeolite to produce the zeolite/magnetic iron oxide nanocomposite (zeolite/Fe3O4 -NCs). The reaction was performed in aqueous suspension phase under the ambient condition as green chemistry method. Characterization with Fourier transforms infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) and transmission electron microscopy (TEM) confirmed the formation of Fe3O4-NPs with mean particle sizes of 3.55±1.02 nm on the surface of the zeolite. [ABSTRACT FROM AUTHOR]

The γ-Al2O3 nanocrystallites were synthesized successfully by combination of sol-gel auto-combustion process and ultrasonic method. The overall process involves three steps: formation of homogeneous sol at 50 °C; formation of dried gel at 90 °C, and experiments revealed that Al2O3 dried gel derived from glycine (as fuel) and nitrates sol exhibits self propagating combustion at 400 °C that it is ignited in air. After auto-combustion process, the Al2O3 nanopowders were calcined at 1100 °C. Also, aluminum alloy matrix composites reinforced with 0.75 and 1.5 vol.% γ-Al2O3 nanoparticles were fabricated via stir casting method. Fabrication was performed at 850 °C temperatures. The resulting composites were tested for their nanostructure and present phases. Based on the obtained results, optimum amount of reinforcement and casting temperature were determined by evaluating the density, hardness and compression tests of the composites. [ABSTRACT FROM AUTHOR]