Sharif Digital Repository

A novel approach is obtained during the fabrication of NiCoFe-B nanotube arrays via electroless method. Porous anodic aluminum oxide (AAO) templates fabricated by anodization of aluminum foil were sensitized using PdCl 2 solution and immersed into electroless plating baths at room temperature to produce nanotube arrays. Compositional and morphological properties of the nanotube arrays are characterized. Results indicates the formation of end-closed nanotubes with the dimension of 100-130 nm in outside diameter, which is determined by the pore size of the AAO template, and about 15 nm in thickness of tube walls. The possible formation mechanism of end-closed metallic nanotube arrays is... 

In this work, energy absorption of ceramic tiles wrapped by aluminum foil on its impact face is experimentally and numerically studied. Penetration tests as well as numerical simulations are employed to obtain Ballistic Limit Velocity (BLV) of the tiles. Experimental and numerical results yield BLV of bare tiles as 145 ± 2 and 141.5 m/s, respectively. For the wrapped tiles, these values are increased to 168 ± 2 and 162 m/s, respectively. Therefore, 13% increase in BLV of the ceramic tiles is obtained by just 2.4% increase in its weight. Moreover, it is shown that energy absorption of the wrapped tiles is at least 11% greater than that of the bare ones. Based on the results, the increase in... 

A novel method based on microextraction in packed syringe (MEPS) as sample preparation technique coupled off-line with gas chromatography-mass spectrometry was developed using electrospun nanofibers as sorbent. For electrospinning of polypyrrole/polyamide-based nanofiber, a homogeneous solution containing nylon 6, ferric chloride and pyrrole monomer was prepared and then was drawn into a 2.5-mL syringe. By applying a voltage of 13akV between the needle of the syringe and an aluminum-foil collector, the nanofibers could be formed on the surface of the collector. The prepared sheet was used as the sorbent for MEPS to analyze some selected organophosphorous pesticides. Important parameters...