Sharif Digital Repository

In recent years, nanodiamond (ND) has been used as reinforcement in polymeric nanocomposites in order to improve mechanical properties, thermal conductivity, etc. The surface of nanodiamond has several functional groups which make it appropriate adsorbent. In this study, nanodiamond was modified with dodecylamine corrosion inhibitor and was utilized (1wt %) in epoxy based nanocomposite. Fourier transform infrared spectroscopy (FTIR) analysis was used to confirm the surface modification of Nanodiamond. In order to estimate the loading amount of corrosion inhibitor, thermogravimetric analysis was investigated. FE-SEM analysis demonstrated nanoparticle dispersibility in epoxy matrix. Regarding... 

One of the ways that corrosion control is presented is the use of coatings that have good properties such as high adhesion, impact resistance, ultraviolet radiation, and so on. They also have other unique properties like anti-corrosion property. To achieve coatings with these advanced properties, they use special properties of nanocomposites. Nanocomposites can add or improve one or more properties to coating properties.In the present study, we tried to first synthesize NanoDiamond/Polyaniline hybrid nanoparticles in different percentages and then use this hybrid in epoxy ester coating. To characterize this hybrid, various analyzes such as FE-SEM, TEM, FT-IR, UV-Visible, TGA and XRD were... 

Water Gas Shift (WGS) reaction is an old reaction in which syngas is used for producing Hydrogen. At the present time, the major application of this reaction is in fuel cells, since the necessary Hydrogen for these cells is provided by this reaction.
The present study investigate the influence of different preparation methods on properties of Cu-ZnO/Al2O3 catalyst for water gas shift (WGS) reaction, which is now known as the Commercial catalyst for low temperature WGS, and its influence on performance of Cu-ZnO/Al2O3 catalyst to derive an optimal Cu-ZnO/Al2O3 catalyst for water gas shift (WGS) reaction. Cu-ZnO/Al2O3 catalysts was synthesized by CP, DP, DP-Ultra, IWI , CP-Urea, and... 

Critical flux is an important parameter in membrane bioreactors, which studying it can give a better understanding of treatment by these bioreactors and make utilizing them easier. In this study, the effect of some sludge properties like it’s concentration, sludge volum index, concentration of protein and carbohydrate in EPS and SMP and the effect of some operating conditions like aeration flow rate and rest mode on critical flux in a submerged membrane bioreactor are investigated. In addition to comparison of TMP-t figures drived from flux step experiment, the hystersis figures are also compared. Finally, two long term experiments at two sub critical fluxes are done in order to study the... 

Dimethyl Ether (DME) is a pure and economic fuel which can be used as a suitable alternative for diesel fuels. Two processes are traditionally used for DME synthesis: producing methanol from synthesis gas and then dehydrating it to DME (direct process), and converting methanol into DME in a catalytic dehydration reactor over a solid-acid catalyst (indirect process), in which the indirect process seems to have economical advantage. In this research, the γ-Al2O3 catalyst was synthesized through precipitation process and then characterized by powder X-ray diffraction (XRD) and porosimetry analysis. Afterwards this catalyst was utilized in methanol dehydration reaction in a slurry reactor. Next,... 

AZ91 is the most applicable alloy of magnesium alloys.Semisolid stir welding of AZ91 magnesium alloy was investigated due to its welding problem such oxide formation, hot cracking in weld metal, and high residual stress through solidification with special focus on the effect of the welding temperatures, stirring rates, and tool shape. The interlayer with thickness of 2mm was located between two AZ91 pieces with 7.5mm thickness. Then, they were heated to the desired temperatures (515C, 530C and 540C), the semisolid temperature of both base metal and interlayer. A grooved stirrer with six rotational speeds from 0rpm to 2000rpm was introduced into the stir weld seam and the welded coupons... 

In this thesis, the value-ladenness or value-neutrality of technology, new social media and as a result Instagram is investigated. It is also discussed whether values can be taken into account during the design process of technical artefacts, including new social media and Instagram, and methods are developed for this purpose. Several methods have been developed for this purpose, some of them and their compatibility with modern social media are explained; including the Value-Sensitive-Design method and the disclosive computer ethics design method. The frameworks of ethical philosophy such as virtue ethics are reviewed and the appropriate ethical framework for the analysis of new social media... 

The characteristics of the brine-crude oil interface in hydrocarbon reservoirs are very important, especially during water-based enhanced oil recovery (EOR) operations such as low-salinity waterflooding. At the interface of the two aforementioned fluids, the interaction mechanisms between the molecules of these two non-miscible fluids would affect capillary forces hence the efficiency of the EOR method. However, based on the published literature, there are still many open questions and uncertainties about the interaction of oil and brine molecules at the interface and their roles in the interfacial tension (IFT) changes for different oil and brine compositions. In this regard, molecular...