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yaghmaei--sohila
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Design of Amniotic Membrane-based Hydrogel for Cardiac Tissue Engineering Application
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Sohila (Supervisor) ; Saadatmand, Maryam (Supervisor)
Abstract
Mammalian cardiac tissue lacks the ability to effectively self-regenerate following severe damage. The application of external therapeutic agents with strong mechanical properties is needed to restore its function. Even though conventional therapies have several challenges and limitations, injectable hydrogels, with minimally invasive, can significantly improve cardiac tissue regeneration. Extracellular matrices are the most appropriate biomaterials for synthesizing cardiac scaffolds. The human amniotic membrane obtained from the amniotic sac is a readily available, abundant, and inexpensive candidate that has been successfully utilized for the clinical treatment of cardiac diseases....
Modeling and Simulation of Alcoholic Fermentation of Sugarcane Blackstrap Molasses
, M.Sc. Thesis Sharif University of Technology ; Yaghmaee, Sohila (Supervisor)
Abstract
Fed-batch fermentation is a valuable and cost-effective method for bio-based production of various products such as ethanol, which has various applications in various industries.In recent years, bioethanol production has been given special attention in many countries. For this reason, the mathematical modeling of production of these products is very important for their optimal and cost-effective production. Given the transient and dynamic nature of fermentation and its specific complexity, mathematical modeling of fed-batch bioreactors is difficult and complicated. In this research, an unstructured model was used to predict the production of ethanol from blackstrap sugar cane molasses based...
Studies on treatment of carbonaceous wastewater by Fixed Film Aeration Tank
, Article Scientia Iranica ; Volume 9, Issue 1 , 2002 , Pages 47-52 ; 10263098 (ISSN) ; Sharif University of Technology
Sharif University of Technology
2002
Abstract
In this paper, a modified activated sludge process using a Fixed Film Aeration Tank (FFAT) was investigated as an improvement for the usual activated sludge or trickling filtration processes. The aeration tank of the system was arranged with fixed parallel saran nets, which were set vertically as supporting media for microbial growth. A carbonaceous solution was brought into contact with microorganisms in the media and was oxidized aerobically. Filamentous microorganisms predominantly grew on the films and the COD removal increased with the increase in accumulated biomass in the system. Simulation of treatment performance in the system was carried out using mathematical models. The...
A study of Acidithiobacillus Ferrooxidans DSMZ 583 Adaptation to Heavy Metals
, Article Iranian Journal of Biotechnology ; Volume 9, Issue 2 , 2011 , Pages 133-144 ; 17283043 (ISSN) ; Ghobadi, Z ; Sharif University of Technology
2011
Abstract
In this study the ability of Acidithiobacillus ferrooxi-dans, with regard to the biorecovery of heavy metals in shake flask has been investigated. Adaptation experiments with the single metal ions Ni, Co, V, Mo, W and a mixture of the first four metal ions in the medium was developed through serial sub-culturing. Adaptation showed that A. ferrooxidans could tolerate up to 2.3 g/l Ni, 1.4 g/l Co, 1.4 g/l V, 0.045 g/l Mo and 0.005 g/l W, singly. In the presence of multi-metals considering a mixture of Ni-Co-V-Mo, the bacteria was able to tolerate up to 1.5 g/l Ni, 0.8 g/l Co, 0.8 g/l V and 0.05 g/l Mo in steps of 50-100 mg/l for Ni, Co and V, while for Mo and W with increments in concentration...
Estimating Volatile Organic Compound emissions from wastewater circulating aeration tanks
, Article Scientia Iranica ; Volume 12, Issue 3 , 2005 , Pages 300-305 ; 10263098 (ISSN) ; Rashidkhani, A ; Sharif University of Technology
Sharif University of Technology
2005
Abstract
The need for the control of Volatile Organic Compounds (VOCs) has led engineers to modify wastewater aeration tank systems. In this research, air recirculation has been investigated as a possible VOC control strategy for these systems. A steady-state mathematical model of VOC emission rates has been developed from the fundamentals of VOC convection, volatilization and biodegradation. This model has been used to study the effect of aeration recirculation in enhancing the biodegradation of VOCs in the system, using dichloromethane as a typical VOC. A feasibility study considering plants of various sizes is needed to compare the costs and benefits of air recirculation to other VOC control...
Optimization of Effective Parameters in Biological Extraction of Mo and Ni from Spent Catalyst
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
During oil refinement, solid catalysts which contain metals such as aluminum, tungstan, molybdenum and nickel are highly used. Following several times reductions and re-applications, their activity potentiality is decreased in a such a way that they can not be re-used., as a result of which they are treated as solid waste. Based on natural potentiality, microorganisms are defined as convertibles of solid compounds to extractive forms and soluble materials. This project aims at finding other factors that have more impact on biological extraction and determining optimal conditions for biological extraction in order to reach maximum extraction efficiency within discontinuous conditions. The...
Choosing a Suitable Microalgae for Bioremediation of Heavy Metals Regarding Iran's Clamate
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
The pollution of water resources with heavy metals as a result of industrial activities threatens the lives of all living organisms. Therefore, separation of heavy metals from wastewater before entering our invironment is very important. Various chemical and physical methods such as absorption, chemical precipitation, extraction by solvent and ion exchange can be used to separate heavy metals but each of these methods have their own problems such as imperfect separation of heavy metals, need for expensive facilities and refining systems, high energy consumption and leaving pollutant residuals that need to be separated. On the other hand, the methods mentioned above can not separate heavy...
Experimental Studies for Lactase Immobilization on the Polymer base and Characterising
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
Immobilization of β-D-galactosidase represents an important approach for development of lactose hydrolysis technology.Chitosan proved to be an excellent carrier for β-Dgalactosidase immobilization, by both covalent binding and sol-gel entrapment combined with adsorption. Among different preparation methods of chitosan support particles for covalent binding, emulsion cross-linking was the most efficient, producing narrow-sized microspheres, without aggregation.The best process parameters of β-D-galactosidase immobilization by covalent coupling on chitosan microspheres were found as 3% glutaraldehyde cross-linker concentration, enzyme loading of 27 mg protein/g dry support, 6 h reaction time,...
Experimental Study of Hydrogen Production from Dairy Wastewater in the Annular Microbial Electrolysis Cell (AMEC)with Spiral Anode
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
In this project, energy in form of electricity and hydrogen was produced in microbial fuel cell and microbial electrolysis cell respectively. For reducing costs, a stainless steel mesh with graphite coating was used as anode electode. Also for increasing efficiency, anode was positioned in cells in a spiral mode. Efficiency of cells was investigated in batch and continuous mode. In this research, dairy wastewater was used as substrate.This wastewater not only has severe emissions, but also is high energy content. In the field of dairy wastewater treatment and hydrogen production in an microbial electrolysis cell wasn’t observed any article.At the first, wastewater was treated in two...
Computational Fluid Dynamic (CFD) of Fixed-Bed Reactor for Bio-treatment of Sulfur from Petroleum Cuts
,
M.Sc. Thesis
Sharif University of Technology
;
Yaghmaei, Soheila
(Supervisor)
Abstract
Bio-desulfurization is the sulfur removal process from organosulfur compounds by the action of microorganisms (which are capable of removing sulfur). Too many studies have been carried out in the use of biocatalysts for BDS process. In this project, we have used data obtained from a previous experiment in which a trickle bed reactor (diameter: 0.066 m, height: 0.6 m) and a Rhodococcus sp. 12891 starin immobilized on bed particles are used to produce diesel with low sulfur content. Sulfur concentration of inlet diesel is between 200ppm to 540 ppm. parameters of process are recycle Ratio , volumetric flow rate and sulfur content of inlet diesel.
A mathematical model for trickle bed...
A mathematical model for trickle bed...
Feasibility Study on Isolation of Native Microorganism for Bioleaching of Electronic Waste
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
Accumulation of electronic wastes in the environment is one of the recent ecological problems. This type of wastes contain metallic and non-metallic elements which can contaminate the environment. On the other hand due to the high volume of precious and basic metals within e-waste, it could be considered as a secondary resource. Bioleaching is a suitable method for the recovery of metals from e-waste which, on the contrary to the conventional recycling methods in the industry, is both economically and ecologically efficient. The aim of this research is the isolation of native micro-organism and evaluating its ability in recovering copper from a mixture of computer, cellphone, fax and copy...
Biorecovery of heavy metals from oil waste water by adapted Thiobacillus Ferrooxidans
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
Acidophilic microorganisms such as Thiobacillus ferrooxidans have the capability to carry out process of biorecovery of heavy metals. Its principle is the microbial production of the sulphuric acid and simultaneous recovery of metals. Acidithiobacillus ferrooxidans derives the energy for their metabolism from ferrous iron oxidation process which can be affected by the presence of heavy metals in the medium. In this study the ability of Acidithiobacillus ferrooxidans, on the biorecovery of heavy metals in shake flask has been investigated The adaptation of the Acidithiobacillus ferrooxidans to a kind of heavy metal such as Nickel, Cobalt, Vanadium, Molybdenum, Tungsten and the mixture of the...
Some Studies on Ability of Aspergillus Niger Mould in Recovery of Heavy Metals from Crude Oil Sludge.
,
M.Sc. Thesis
Sharif University of Technology
;
Yaghmaei, Soheila
(Supervisor)
Abstract
This study focused on the tolerance of fungi strains including Aspergillus niger, Aspergillus foetidus and Penicillium for different metals (Ni, Co, Mo, V, Mn, Mg, Fe, W and Zn ). Then Aspergillus niger was exposed to mixture of Mo, V and Mn (at a mass ratio of 1:2:6 as approximately present in the spent refinery processing catalyst). The degree of tolerance was measured from the growth rate in the presence of various metals and compared to a control which contained no metals. Effect of type of strains, type of metal and metal concentration on adaptive tolerance of fungus was evaluated. Adaptation experiments with single metals showed Aspergillus niger tolerated up to 1000 mg/l Ni, Zn, 1500...
Experimental Investigation of Effective Parameters on Performance of Micro-sized Bio-electrochemical Systems
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
This study is a report on the fabrication of a novel single-chamber micro-structure microbial fuel cell consisting of spiral anode chamber. A 3×3 cm plexiglass plate with 1 mm thickness was used as main body. A spiral microchannel (1 mm in width and 226 mm in length) was cut using a laser beam as an anodic compartment. Two types of microbial fuel cells with the same anode electrode (stainless steel mesh) and different cathode electrodes (stainless steel mesh and carbon cloth) were constructed in order to investigate the effect of cathode electrode material on microbial fuel cell performance. In both batch and continuous mode, higher power density was obtained by microbial fuel cell with...
Elimination of Environmental Problems Caused by Leakage of Electrical Transformers Fluid (Askarel) by Biological Methods
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
Polychlorinated biphenyls are a group of hydrocarbons that are composed of two benzene rings and chlorine admixture on it. Due to their special properties, these materials were added to oils for years to improve their properties. These compounds have many industrial applications in various industries, such as the production of fluorescent lamps, adhesives, dyes, and especially as a cooling and insulating liquid as the Askarel oil in power transformers. Due to the properties of these compounds, which include stability and bioaccumulation in fatty tissues, the wide use of these substances causes environmental contamination and leads to a variety of cancerous diseases. Among the cleaning...
Optimization of the Capability of Native Microorganisms Isolated from the Landfill of Electronic Wastes in Bioleaching of E-Waste
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
Given the complex structure of electronic waste and the difficulty of recycling it by traditional methods, the focus is mainly on biohydrometallurgy method, and in particular on bioleaching. To recover metals, various microorganisms are utilized in this method. In light of previous studies, cyanogenic bacteria have been widely used for the extraction of basic and precious metals. Among the species, indigenous microorganisms have a higher ability to resist toxic environments in the bioleaching of metals due to their adaptation by rapid changes in their metabolic system over time. The main objective of this study is to isolate indigenous microorganisms from electronic waste landfill for their...
Investigating Different Methods of Coating the Polyaniline on Anode Electrode and its Effect on Microbial Fuel Cell Performance
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
In this research, different methods of coating polyaniline on the anode electrode and its performance in a microbial fuel cell, and a chemical method for making polyaniline / graphene catalyst on a cathode electrode and its performance in microbial electrolysis cell electrode were investigated. There are two main goals in this study. First, the production of polyaniline and the comparison of the surface morphology of this fiber with other forms of polyaniline on the surface of the electrode and its effect on the performance of the microbial fuel cell and the second, the production of polyaniline / graphene catalyst in the cathode electrode and its comparison with the platinum catalyst in the...
Degradation of azo dye methyl red by saccharomyces cerevisiae ATCC 9763
, Article International Biodeterioration and Biodegradation ; Volume 125 , 2017 , Pages 62-72 ; 09648305 (ISSN) ; Bagheri Lotfabad, T ; Heidarinasab, A ; Yaghmaei, S
2017
Abstract
Azo dyes are common dye groups widely used in different industries. Industrial effluents which contain these dyes pervade water resources and have various known and unknown physiological effects on living organisms. In this study, methyl red (MR) was proposed as a model azo dye to examine the capability of Saccharomyces cerevisiae ATCC 9763 for cleavage of the azo bond leading to decolourization. The spectrophotometry method showed that complete decolourization occurred statically during ≃12 h and this time reduced to several minutes less than 10 min where cell mass increased. Thin layer chromatography (TLC), mass spectroscopy and Fourier transform infrared (FTIR) confirmed degradation of...
Experimental Study of Biological Removal of Cyanides in the Effluent of Coke Oven of Esfhan Steel Company
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor)
Abstract
The presence of highly toxic cyanides in the effluent of coke oven of steel industries is considered as a critical problem. Owing to high levels of toxicity, control and removal of cyanide are of great importance in this industry. Biological removal of cyanides by indigenous microorganisms offers inexpensive, safe and environmentally compatible option in comparison with chemical and physical methods. The present study primarily focused on the isolation and purification of the microorganisms which utilize cyanide as the sole source of Nitrogen in alkaline conditions. The isolated bacterial strains were investigated through variety of bacteriological and biochemical reactions as well as...