a. r. souri

Topological characterizations and optical density of the synthesized hydrogenated amorphous carbon Cu-Ni NPs @ a-C: H nanotubes (CNTs) with different surface morphology were studied in this report. Films deposited with Ni layer thickness of5 nm have a maximum value of optical density especially in high energy range. Steps between 1800 to 2000KeV in the Rutherford backscattering (RBS) spectra are correspond to the presence of Cu and Ni elements. The thicknesses of films were measured by using SIMN-RA software. Films deposited with Ni layer thickness of 15nm have a maximum value of the lateral size of nanotubes in about 19.7nm.The grown CNTs of films deposited with Ni layer thickness15nm Ni, has a maximum value of diameter in about 16.2nm. The diagram of bearing area proportion height shows the percentage of cavities and single-layers. The cavity coverage of films was less than 5% and the layer content of films was about 90%.

Owing to their high strength-to-weight ratio, aluminum-ceramic composites, are widely used in various industries. In this study, aluminum matrix composite was fabricated with only 2 wt% micron-sized SiC particles as the reinforcing phase using electromagnetic stir casting. Prior to mixing, the surface of SiC particles were chemically etched by HF, NaOH, and KOH at two heat treatment temperatures of 460 and 510 °C for 30 min. The obtained results indicated better wettability and interaction between the etched SiC particles and Al matrix. In addition, etched SiC particle as a ceramic phase at 460 °C enhanced the mechanical properties of Al as a metal matrix, such as enhancing hardness and E about of 6.6 and 26.6%, respectively, mainly due to the increasing inhibition against movement of dislocation confirmed by the observed brittle behavior of fracture surface.

The current article is the result of a field research conducted in 2008 aiming to examine the grounds in which organizational models and modern cash raising strategies are implemented. For this purpose, the viewpoints of 31 experts in the cooperation sector were evaluated. The findings of this study showed that by communicating the general policies of the 44th Article of the Constitution, fundamental changes will occur in the organizational model of the cooperative and cash raising strategies, lifting many of the legal restrictions for cash raising cooperatives and allows cooperatives to enter various fields, including banking. For this purpose, it's been tried to shatter the framework of traditional models in local and foreign cash raising and replacing them with modern tools so that the framework of cooperative's organizational model in Iran transforms from traditional model to joint stock cooperatives (i.e. investors) which are now implemented in countries with strong theoretical and practical structure. Cooperative's cash raising strategy also shall incline towards support cash raising, especially direct cash raising instead of traditional cash raising strategy. Evaluating the viewpoints of experts also showed that traditional cooperative organizational model has been ineffective for cash raising and other organizational models, especially the organizational model of transforming to capital based company, has been very effective. Cash raising strategies has also been effective, except subsidiary debt methods in traditional cash raising strategy, capital reserves in the unit in the support cash raising strategy and receiving securities from members in the direct cash raising strategy.