Sharif Digital Repository

Housing is one of the important staple goods. The main different between housing market and the other markets is limitation of stock at short term. So it is very important to regularize housing market for apropos accountability and according to society consumption demand. This document introduce the result of an agent based modeling of housing market. There are agents that find out the maximum utility for choosing one of following house related conditions: purchase, sale and lease agreement. In fact in this model people have two phases. The effect of land value taxation for regularization of housing market will analyses with this model. Its seems that by implementation of mentioned tax, the... 

Although the origin of matter-antimatter asymmetry remains unknown, continuing advances in theory and improved experimental limits have ruled out some scenarios for baryogenesis: for example, the sphaleron baryogenesis at the electroweak phase transition in the standard model. In this thesis, we give an introduction to some of the ideas and attempts to understand the origin of the matte -antimatter asymmetry of the universe. After the discussion of some basic issues of cosmology and particle theory, the scenarios of electroweak baryogenesis, GUT baryogenesis, and leptogenesis are outlined  

The study of thermodynamics of small-scale systems or quantum thermodynamics has been recently receiving a lot of attention from quantum scientists in the field of quantum information. The main purpose of this thesis is to review the effects of quantum phenomena such as correlations, on the laws of thermodynamics and specifically on the efficiency of quantum heat engines. We first review some of the most important topics of classical thermodynamics such as the laws of thermodynamics, thermodynamic potentials and heat engines. The trade-off between power and efficiency for classical heat engines is investigated. It is shown that, this is impossible to have a heat engine performing with the... 

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... 

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... 

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,... 

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... 

The high consumption of worldwide fossil energy and its detrimental effects on the environment and climate have prompted a transition toward renewable energy sources. The availability of renewable energy sources depends on weather and seasonal changes; therefore, an imbalance between supply and demand would be unavoidable. Hydrogen storage as an energy carrier, can fulfill this energy mismatch. Storing hydrogen in underground formations, such as aquifers, has been the subject of extensive research recently. In these storage reservoirs, hydrogen contacts the resident brine which will be lost through the dissolution-diffusion mechanism. Therefore, successful design of these storages requires... 

Various studies have confirmed that water salinity and its composition significantly affect the efficiency of the waterflooding process. Field-scale operation of low-salinity water injection has been proven to be a cost-effective enhanced oil recovery (EOR) method which is also compatible with the environmental regulations. Although this method has satisfactory results, it faces some challenges, such as in-situ mixing of the injection low-salinity water with the saline water in the host reservoir. The salinity of the injected water increases, as it contacts the high-salinity reservoir brine in the pores. This phenomenon significantly impairs the efficiency of this technique, and increases...