The most important reason for the design of curved tubes is increasing the heat transfer between the fluid and the wall which has provided many applications in various industries such as air conditioning, micro-electric, heat exchangers and etc. The aim of this study is numerical investigation of nano fluids flow in spiral tubes with injection of base fluid in different Reynolds numbers. Accord...

The addition of magnesium to Aluminum alloys has become increasingly popular due their lightweight, high strength, and corrosion resistance properties. Our research on high-content Mg doped 90, Al-10 wt% alloy shown that coating it with electroless Ni-P codepositing nano-Al2O3 (0, 2.5, 5 7.5 wt%) can significantly improve its mechanical properties, wear & tear, even resistance. Ni-P-5 Al2O3...

A first-principles study of the vibrational modes of PbTiO3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone ~BZ!. The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at the G point, including the LO-TO spli...

In this paper, the production of Al2O3-Mo nano-composites via mechanical milling was investigated. Molybdenum and alumina powders with certain ratios were grounded in a planetary ball mill at different times. XRD technique was used to determine the crystallite size of the milled powders. The microstructure of milled powders was studied using optical and electron microscopes. The crystallite siz...

The Knoevenagel condensation of aromatic aldehydes with barbituric acid, dimedone and malononitrile occurred in the presence of BF3/nano-γ-Al2O3 at room temperature in ethanol. This catalyst is characterized by powder X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energy-disper...

The interlayer adhesion in the multilayered micro-devices is of significant importance for their electronic properties. scratch test applied here using a micro-blade sliding under linearly increased load, combined with optical and SEM visualization, to study Al2O3/GR/SiO2/Si Al2O3/hBN/GR/SiO2/Si stacks. failure interlayers determined by critical load at which sudden change coefficient friction ...

The scientific importance of nanocomposites are being increased due to their improvedproperties. This paper is divided into two parts. First, Al-Al2O3 nanocomposite wasproduced by using ball milling technique followed by cold compaction and sintering.Microstructure and morphology studies were done through SEM, TEM, and EDX anal-ysis on the produced powder. The mechanical properties of the produ...