Development of Microorganisms with Improved Biosurfactant Activity

, Ph.D. Dissertation Sharif University of Technology Bagheri Lotfabad, Tayebe (Author) ; Roosta Azad, Reza (Supervisor) ; Rouholamini Najafabadi, Abdolhossein (Supervisor) ; Akbari Noghabi, Kambiz (Co-Advisor) ; Shahcheraghi, Fereshte (Co-Advisor)

Abstract

This thesis discusses the work on the production of a rhamnolipid-type biosurfactant by Pseudomonas aeruginosa MR01, its structural characterization and environmental applications. First, results from analytical approaches for screening of biosurfactant producers suggested the oil spreading method as the fastest, simplest and most consistent analytical method. The second part of the thesis describes the properties of the most efficient biosurfactant-producing bacteria isolated from oil fields in south of Iran and according to it’s biochemical characteristics and partial sequenced 16S rRNA gene affiliated with Pseudomonas aeruginosa. Time course study indicated that the maximum biosurfactant...

Evaluation of dynamic properties of a calcite cemented gravely sand

, Article Geotechnical Earthquake Engineering and Soil Dynamics IV Congress 2008 - Geotechnical Earthquake Engineering and Soil Dynamics, Sacramento, CA, 18 May 2008 through 22 May 2008 ; Issue 181 , 2008 ; 08950563 (ISSN); 9780784409756 (ISBN) Haeri, S. M ; Shakeri, M. R ; Shahcheraghi, S. A ; Sharif University of Technology

2008

Abstract

Understanding of the effect of cementation on dynamic behaviour of cemented soil in an earthquake prone area could be crucial for earthquake resistance design. The major section of the city of Tehran has been developed on cemented coarse-grained alluvium. In order to understand the dynamic behaviour of this soil, a series of undrained cyclic triaxial tests were performed on uncemented and artificially calcite-cemented samples. In this paper, two dynamic parameters including dynamic shear modulus and damping ratio based on different definitions are investigated. In this regard the effects of cement content, confining pressure and cyclic deviatoric stress were studied as well. In general by...

Studying and Synthesize of H2S Gas Sensors Based on Modified WO3 Nanostructure Thin Films

, M.Sc. Thesis Sharif University of Technology Kashani, Shima (Author) ; Iraji zad, Aazam (Supervisor) ; Rahimi, Fereshte (Co-Advisor)

Abstract

H2S is a toxic gas used in chemical laboratories and industries. H2S is also liberated in nature due to biological processes and also from mines and petroleum fields. At some threshold level, exposure to concentrations over 10 ppm can result in headaches, irritability, dizziness and in some case leads to death. So that introducing sensors which sense H2S at ppm level with the low response time is so essential. The present work emphasizes on H2S resistance-sensing properties of pure and Pd doped WO3 films prepared by Arc discharge method. XRD, SEM, EDAX and XPS were applied to analyze crystal structure, morphology and chemical composition of the films. The analyzes results showed that films...

Molecular Property Prediction Using a Graph based Deep Learning Method

, M.Sc. Thesis Sharif University of Technology Shahcheraghi, Shamim (Author) ; Hossein Khalaj, Babak (Supervisor) ; Soleymani, Mahdieh (Supervisor)

Abstract

The goal of drug design is to identify new molecules with a set of desirable properties. The molecular search space is large, discrete, and unstructured, which results in a prolonged construction and testing process of new compounds and requires significant costs. Furthermore, there is a wide variety of appealing options to choose from. Recent advances in the field of machine learning have led to the emergence of generative models that, after training on real examples, can suggest suitable molecules with less time and cost. One of the stages that should be considered in the path of drug production is predicting the properties of the chemical molecule and its effect on the desired protein. By...