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Research Subject: Nowadays, application of biosurfactants in microbial enhanced oil recovery (MEOR) have aroused much attention and several investigations have been conducted on this field. But their performance in comparison to synthetic surfactants in enhanced oil recovery has little been studied. Most of these researches are limited to comparison of one produced biosurfactant with only a chemical surfactant. To fill this gap, in this research, the potential use of a rhamnolipid type biosurfactant  in MEOR was compared to several conventional synthesized surfactants: SDS, SDBS, CTAB and DTAB.
Research Approach: Since the main goal of this research is the comparison between produced biosurfactant and conventional chemical surfactants in oil recovery, several flooding tests were conducted and involved mechanisms were investigated. All of tests were conducted in an oil wet glass micromodel saturated with heavy oil at ambient condition. Injected solutions were prepared at critical micelle concentration of surfactants. During the flooding tests, high quality pictures were taken with a camera connected to the computer to monitor the motion of injected solution in the micromodel.
 Main Results: 40% oil recovery was achieved after biosurfactant flooding while SDBS, SDS, CTAB and DTAB resulted 36%, 34%, 32% and 29% oil recovery, respectively. For mechanistic study, the surface tension (ST) and viscosity measurements were performed and contact angle was determined. The surface tension reduction, wettability alteration towards more water-wet condition and increasing the ratio of injected fluid viscosity to oil viscosity were dominant mechanisms. The rhamnolipid was more effective than other surfactants in reduction of surface tension and altering the wettability towards favorable water-wet conditions. It decreased the surface tension of water from 72 to 28 mN/m, which was the least comparing to other surfactants and increased the capillary number about 19.4 times greater than in water flooding. Additionally, it changed the contact angle from 106 to 6, 94.3%, the widest change among applied surfactants. 

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Research subject: The use of nanoparticles, especially nano-antibiotics, increases their efficacy. More uniform release of antibiotics is one of the benefits of being nano. They can also be made using ointment or banderol to absorb through the skin to the infection, thereby reducing its side effects. Amoxicillin is one of the most widely used antibiotics in the world which can be prevented by increasing the use of other strong antibiotics if promoted as nanoparticles. Determining the mechanism of nanoparticle formation of this drug is an important factor for its commercial production.
Research approach: The purpose of this study was to determine the nucleation mechanism and time of induction of crystallization of amoxicillin nanoparticles in the presence of surface active agents ‘CTAB’ and ‘SDS’. Therefore, the effect of amoxicillin concentration and stabilizing concentration on the crystallization process was investigated. In this project, a combination of inductive-reactive crystallization was used. In this method, amoxicillin sodium was produced with sodium hydroxide, amoxicillin sodium, has a much higher solubility in water. Then, by adding hydrochloric acid, amoxicillin will be recovered and supersaturated. SEM and DLS analyzes were used to determine the properties of amoxicillin nanoparticles. All the experiments were repeated twice.
Main results: The results show that particles with a mean size of 50 nm were formed, and the particle stability was confirmed up to one week after formation. The results of the experiments show that the nucleation mechanism is the primary type with an average explanatory factor (R²) equal to 0.9887 and adding a stabilizing agent has no effect on the nucleation mechanism.

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Nanomaterials have been used in the recent years to improve rheological properties of the asphalt binders and increase mechanical properties of the asphalt mixtures. The high cost of producing nanomaterials is one of the major obstacles that has limited their application in road pavements. In this research, two methods of producing nanomaterials have been applied to produce nano hydrated lime (NHL). The first method was a mechanical process of milling hydrated lime with the application of a planetary ball mill. The second method was chemical processing of dissolving certain chemical materials (namely, calcium nitrate Ca(NO₃)₂, sodium hydroxide NaOH and sodium dodecyl sulfate SDS) into distilled water. The process resulted in the production of NHL solution that after drying in an oven resulted in NHL particles. The sizes of the NHL products were measured using two methods of Field Emission Scanning Electron Microscope (FE-SEM) and Dynamic Light Scattering (DLS). The size analysis was performed on NHL samples that were produced after different milling periods in the physical method; and, variation of the concentration of the solution, mainly calcium nitrate and SDS, in the chemical method. The average particle sizes in the physical method, after 6 hours of milling, were 211 nm, as measures in DLS and 114 nm as measured in FE-SEM. These in the chemical method, at concentration of 3 ml of calcium nitrate solution (Ca(NO₃)₂), were 379 and 124.615 nm respectively. With the chemical method, the nano particles were formed in the plate form with average thickness of 68.5 nm. In addition, X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis were performed in order to determine the composition of the produced nano materials. These indicated that with the physical method, a higher lime content material was produced. With the aim of assessing the effectiveness of the produced NHL materials to modify asphalt binders, a 60-70 and an 85-100 penetration grade were used and nano modified binders containing 2, 4 and 6% NHL were prepared and were tested under standard bitumen tests and viscosity determination. The results indicated that with adding NHL to the asphalt binders, penetration was reduced and softening point was increased. In addition, the temperature susceptibility of the modified binders were reduced too. Assessing the change of the viscosity of the NHL modified binders, it resulted that 4% NHL would provide the optimum conditions.