Nanocomposites of polycarbonate (PC)/multiwalled carbon nanotubes (MWCNTs) containing 0.5-3 wt% of MWCNTs were prepared via two methods of melt mixing and solution mixing. The effect of CNT content and processing methods on electrical and electromagnetic properties of nanocomposite samples were investigated. TEM microphotographs revealed that the PC/ MWCNT composites prepared by the solution method, have better dispersion and distribution of CNTs in the PC matrix. Electrical measurements indicated an electrical percolation threshold of less than 1 wt% of CNTs for this system. Also, it was found that PC/MWCNT composites prepared by the solution method, exhibit higher electrical conductivity and lower electrical percolation threshold. The electromagnetic interference shielding effectiveness (EMI SE) measurements in the X-band (8.2-12.4 GHz) indicated that EMI SE is increased by increasing the amount of CNTs in the samples, and also the thickness of specimens. In addition, the results showed that the composites prepared by the solution method, have higher SE values. Finally, in order to reach an acceptable value for commercial applications of EMI shielding materials (20 dB), thicker samples were produced and it was found that the 3.5 mm thick samples containing 2 wt% CNTs, have a 19.6 dB shielding effectiveness. POLYM. COMPOS., 38:E269-E276,

Aluminum Oxide and its nanostructures are attracted the attention of researchers due to their special materials properties such as: high electrical insulation, high mechanical strength, corrosion resistance, chemical stability, and low thermal conductivity. Furthermore, Aluminum Oxide nanowires shows large surface area as well as highly electropositive surface, which makes them suitable candidates for water purification technology applications. One of the main challenges, which limited the usage of Aluminum Oxide nanowires, is high cost and complex fabrication methods for Aluminum Oxide synthesizing such as chemical vapor deposition (CVD) techniques. On the other hand, electrochemical methods such as anodizing/etching techniques show high controllability over chemical composition, morphology,and crystalline structure of nanowires. In this research, a room temperature two-steps anodization procedure is developed to fabricate a highly-ordered self-assembled templates. Furthermore, the etching method is used to convert this synthesized self-assembled template into Aluminum Oxide nanowires. The results show that the proposed electrochemical method maintains a highly-ordered morphology as well as industrially acceptable controllability over crystalline structure of nanowires, which could be used to optimize the procedure for industrial applications due to low cost and simple experimental setup.

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<div>Sn and its nanostructures are one of the promising candidates to replace graphite in the anode of Lithium-ion batteries due to their higher capacity.</div><div>One of the challenges, which limited the usage of Sn anodes for the Lithium-ion batteries, is Tin's high volumetric strain and its low cyclability.</div><div>On the other hand, nanostructures show lower volume change during charge/discharge and as a result could address the cyclability issues.</div><div>In this research, an alternating current (AC) electrochemical method is developed in order to facilitate the industrial scale production of Sn nanowires. The developed electrodeposition technique shows reliable controllability over chemical composition and crystalline structure of Sn nanowires. Also, the order structure of nanowires could be adjusted more accurately in comparison to conventional fabrication techniques.</div><div>As a result, the Sn nanowires as well as Aluminum Oxide templates synthesized by using the developed electrochemical method are examined due to their morphology, chemical composition, and their crystalline structure in order to develop a practical relation between electrochemical composition of the solution and materials properties of Sn nanowires.</div><div>The results show that the proposed electrodeposition method maintains a highly-ordered morphology as well as industrially acceptable controllability over crystalline structure of nanowires, which could be used to optimize the procedure for industrial applications due to low cost and simple experimental setup.</div>

We developed a three-dimensional microstructure analysis system based on the manual serial sectioning method to evaluate the heat treatment effects on chromium carbide size and morphology in AISI D2 tool steel. Two heat treatment factors, austenitizing and tempering temperature were investigated. The results show that increasing in austenitizing temperature leads to further carbide precipitation after the tempering process and increasing in the tempering temperature causes precipitate smaller secondary carbides even more than the primary carbides.