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    Removal of Pharmaceuticals from Polluted Water Using Carbon Nanotube-based Membranes Coated with Enzyme

    , M.Sc. Thesis Sharif University of Technology Masjoudi, Mahsa (Author) ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Today, presence of micropollutants, including pharmaceutical compounds, in aquatic systems has turned into a major environmental challenge threatening the health of humans and many aquatic and terrestrial organisms. In the recent years, biodegradation of pharmaceuticals using enzymes, such as laccase, has been presented as a green method for eliminating these types of pollutants. Furthermore, regarding the improved stability and reusability of immobilized enzymes, these types of biocatalysts are suitable for industrial applications. Enzymatic membrane reactor is a promising method of enzymatic treatment and fabrication of a high-efficiency enzymatic membrane is a major step to begin this... 

    Pharmaceutical Active Compounds Removal by Immobilized Laccase on the Membrane

    , M.Sc. Thesis Sharif University of Technology Golgoli, Mitra (Author) ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Pharmaceutical active compounds existence in the water would cause serious ecological risks and human health-related adverse effects which turn to environmental concern, therefore several studies have done to remove pharmaceutical active compounds efficiently. Carbamazepine (CBZ), a widely used psychiatric drug, is one of the most frequently detected compounds in the surface water and groundwater which is studies in the current study. Recently, biocatalytic degradation using ligninolytic enzymes such as laccase provides a promising approach for their removal from water and wastewater. In this work, carbamazepine removal by immobilized laccase on modified membrane by multi wall carbon nanotube... 

    Bioremediation of Polychlorinated Biphenyls Contaminated Soils (with Emphasis on 4-chlorobenzoic acid) by Slurry Systems

    , M.Sc. Thesis Sharif University of Technology Abad, Zahra (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Polychlorobiphenyl compounds are a class of persistent organic pollutants consisting of two biphenyl rings and chlorine substations. Polychlorobiphenyls do not dissolve in water, are very stable at high temperatures, and are considered a good conductor. Due to the mentioned properties in the 1930s and 1940s, these compounds were widely used in various industries such as power plants, Painting industry, Plastics industry, etc. After years of use, these substances have been found to be very dangerous to the health of living organisms and the environment due to their high resistance to decomposition and the ability to accumulate in adipose tissue. Today, although the production and use of these... 

    Removal of Micropollutants using the Combination of Advanced Oxidation Process and Bioreactor

    , M.Sc. Thesis Sharif University of Technology Motahari, Shahriyar (Author) ; Ghasemian, Saloumeh (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
    Abstract
    Micropollutants are a wide group of organic compounds that are detected in most compartments of the environment. Their environmental concentration is usually in the range of few ng/l to mg/l, but they remain biologically active even at such low concentrations; may be accumulated through the food chain, and pose a serious threat to the environment, fauna, and human health. Among micropollutants, pharmaceutical active compounds (PhACs) are of special concern. It is accepted that the main sources of PhACs in the environment are effluents from wastewater treatment plants (WWTPs), where conventional activated sludge processes are not able to degrade most of them. To address these concerns, the... 

    Treatment of Triclosan Through Enhanced Microbial Biodegradation

    , M.Sc. Thesis Sharif University of Technology Ghafouri, Mahsa (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
    Abstract
    Triclosan is widely used as an antibacterial agent in personal health care products, especially in recent years with the spread of the Coronavirus. This substance is one of the emerging contaminants, and due to its stable and toxic nature, this material cannot be destroyed in the process of biological wastewater treatment. In this research, a new bacterial strain was isolated and purified from industrial wastewater for the biological removal of triclosan. Based on 16S rRNA sequencing, it was found that the isolated strain belongs to the Enterobacter cloacae family and can grow in high concentrations of triclosan. It was observed that naphthalene dioxygenase and laccase enzymes are active... 

    Studying of Laccase Immobilization on Nanoparticles for Bisphenol A Removal

    , M.Sc. Thesis Sharif University of Technology Sadeghzadeh, Sadegh (Author) ; Borghei, Mehdi (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Bisphenol A is one of Endocrine Disturbing Chemicals. Enzymatic removal of bisphenol A is an interesting and green method. However, application of enzymes has been hampered due to lower operational stability and lots of difficulties in recovery and recycling. Enzyme immobilization can ba an innovative approach to circumvent these drawbacks. Laccase from Trametes hirsuta used for Bisphenol A removal. Firstly, magnetic nanoparticles were synthesized by coprecipitation method and aminofunctionalized by (3-aminopropyl)-mmethoxysilane. Subsequently, laccase was precipitated with i-propanol in the presence of aminofunctionalized nanoparticles and followed by addition of glutaraldehyde to the final... 

    Experimental Investigation of Polyclorinated Biphenyls (PCBs)Bioremediation

    , M.Sc. Thesis Sharif University of Technology Sharifi Dehsari, Hadiseh (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-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... 

    Bioremediation of Soils Contaminated by Polychlorinated Biphenyls

    , M.Sc. Thesis Sharif University of Technology Dehghani Mohammadabadi, Fatemeh (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Polychlorinated Biphenyls are a class of organic compounds that are composed of two biphenyl rings attached by 1-10 chlorine atoms. Due to their specific properties, such as physical and chemical stability, flame resistance, and dielectric properties, these compounds are used as dielectric liquids, heat-exchange fluids, hydraulic liquids, plastifiers, and especially as Askarel oil in power plant transformer. Because of their high persistency in the environment, high toxicity, and bioaccumulation in the adipose tissue of humans and animals, their production is banned in most countries, and their use has been limited. There are different methods for detoxification of these compounds, and in... 

    Use of Bio-Cementation for Reducing Land Subsidence

    , M.Sc. Thesis Sharif University of Technology Abed, Mahrooz (Author) ; Khosravi, Ali (Supervisor) ; Pak, Ali (Supervisor) ; Ghobadi Nejad, Zahra ($item.subfieldsMap.e)
    Abstract
    Land subsidence is a gradual settling or sudden sinking of the land surface from changes that take place underground. There are different causes of land subsidence; most notably, groundwater overdraft and severe weather conditions. Subsidence of the land surface due to ground water overdraft is caused by an increase in the intergranular pressure in unconsolidated aquifers, which results in a loss of buoyancy of solid particles in the zone dewatered by the falling water table and accordingly compaction of the aquifer. In this study, an experimental approach was developed to examine applicability of Microbially induced carbonate precipitation (MICP) for land subsidence control under... 

    Investigation of the Effects Of Microbially-Induced Calcium Carbonate Precipitation on the Soil-Water Retention Curve and Changes of Small Strain Shear Modulus of Unsaturated Sand During Drying Path

    , M.Sc. Thesis Sharif University of Technology Jahanbakhsh, Yashar (Author) ; Pak, Ali (Supervisor) ; Khosravi, Ali (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor)
    Abstract
    Microbially-induced calcium carbonate precipitation is a low-cost, environmentally friendly, novel ground improvement technique that has received much attention in recent years. Most studies on biological soil stabilization have investigated the mechanical and hydraulic behavior of soils in dry and saturated conditions. However, the behavior of soils stabilized by this method in the unsaturated state should be of immense concern through the extent of unsaturated soils in nature. Therefore, this study aims to investigate the effects of microbially-induced calcium carbonate precipitation on the soil-water retention curve and changes of small strain shear modulus of unsaturated cemented and... 

    Synthesis, Characterization and Applications of Antibacterial Metal-Organic Framework Nanocomposites for Water Remediation

    , M.Sc. Thesis Sharif University of Technology Talebi Deylamani, Sara (Author) ; Borghei, Mehdi (Supervisor) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Contaminants in drinking water, including microbial contaminants, have a great impact on the health of people in the community and can seriously threaten public health. In recent years, diseases caused by pathogenic bacteria due to the consumption of contaminated water have led to many deaths. As a result, water treatment has been one of the most important human concerns. Among the new water treatment technologies, metal-organic(MOF) frameworks are a new generation of porous materials that have properties such as high surface area, water stability and functionality due to their dual structure. As a result, they are widely used today in various scientific fields, including water purification.... 

    Isolation and Identification of Native Microorganisms Capable of Biological Degradation of Microplastics and Evaluation of its Performance in the Degradation of These Microplastics

    , M.Sc. Thesis Sharif University of Technology Kashisaz Shahriyar (Author) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Supervisor) ; Hamzehluoyan, Tayebeh (Supervisor)
    Abstract
    In recent years, non-biodegradable microplastics (MPs), which cause a lot of pollution in the environment, have become a major concern worldwide. Due to their small size and large surface area, these plastic particles have a great ability to be absorbed into biological cells. Due to their hydrophobic surface, these particles have the ability to absorb pollutants such as heavy metals, toxic medicinal substances, softeners, etc. Microplastics are usually persistent in the environment, allowing them to be transported along the food chain. Research on the degradation of microplastics is focused on biological and non-biological approaches. To date, microorganisms such as algae, fungi, and... 

    Constructing Calcite Core by Microbially Induced Calcite Precipitation (MICP) Usable in Oil and Gas Tests

    , M.Sc. Thesis Sharif University of Technology Ali Doust Salimi, Nazanin (Author) ; Yaghmaei, Soheila (Supervisor) ; Bazargan, Mohammad (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
    Abstract
    Acidizing is the most widely performed job to remove the formation damage, and enhance the oil recovery. Different models have been introduced to design the optimized condition for acidizing. However, none of them are able to predict the optimum injection flow rate in the actual application. As a result, Calcite cores are extracted from reservoirs for conducting experiments and modifying the present models. Nevertheless, acidizing is an intrusive technique destroying the costly extracted cores. Thus, there is a need to construct calcite cores of various porosities and permeabilities to take advantage of them in acidizing modelling.Microbially induced calcite precipitation is a well-known... 

    Biodegradation of cyanide under alkaline conditions by a strain of pseudomonas putida isolated from gold mine soil and optimization of process variables through response surface methodology (RSM)

    , Article Periodica Polytechnica Chemical Engineering ; Volume 62, Issue 3 , May , 2018 , Pages 265-273 ; 03245853 (ISSN) Moradkhani, M ; Yaghmaei, S ; Ghobadi Nejad, Z ; Sharif University of Technology
    Budapest University of Technology and Economics  2018
    Abstract
    In regard to highly poisonous effects of cyanide ion, concerns have been focused recently on treatment of such compounds in different ways. Four bacterial strains (C1-C4) capable of using cyanide as nitrogen source were isolated from contaminated gold mine soil samples under alkaline conditions at 30 °C, pH 9.5-10.5, and agitation speed 150 rpm. The gram-negative bacterium C3 (identified as Pseudomonas parafulva NBRC 16636(T) by 16S rRNA gene sequencing) was able to tolerate cyanide up to 500 ppm besides removing 93.5% of 200 ppm cyanide in 13 days which was confirmed by microorganisms growth. The addition of basal salts enhanced the removal efficiency of C3 by 16%. Cyanide removal... 

    Production of extracellular protease and determination of optimal condition by bacillus licheniformis BBRC 100053

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 22, Issue 3 , 2009 , Pages 221-228 ; 1728-144X (ISSN) Ghobadi Nejad, Z ; Yaghmaei, S ; Haji Hosseini, R ; Sharif University of Technology
    Materials and Energy Research Center  2009
    Abstract
    The production of protease by Bacillus licheniformis BBRC 100053 was studied. The most appropriate medium for the growth and protease production is composed of: lactose 1%, yeast extract 0.5%, peptone 0.5%, KH2PO 4 0.1%, MgSO4.7H2O 0.02%. Enzyme production corresponded with growth and reached a maximums level (589 U/ml) during the stationary phase at 35°C, pH equivalent to 10 and with 150 rpm after 73 hours. Protease activity was highest at pH 8 and 45°C. The best carbon sources are respectively lactose and maltose and the best nitrogen source is peptone. The protease was highly active and stable from pH 7.0 to 11.0 with an optimum at pH 7-8.... 

    Biodegradation of synthetic dye using partially purified and characterized laccase and its proposed mechanism

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 12 , 2019 , Pages 7805-7816 ; 17351472 (ISSN) Ghobadi Nejad, Z ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2019
    Abstract
    The supernatant obtained from the extracellular laccase produced by Phanerochaete chrysosporium was used as the enzyme source to conduct a partial purification, characterization and dye decolorization study. The partially purified enzyme was stable in the pH range of 3–5 and showed an optimum activity at pH 4.0, using guaiacol as a substrate. Laccase stability of pH was determined and discovered to retain 100% of its activity at a pH of 4.0 after 2 h. The maximum enzyme activity was obtained between 30 and 50 °C. The maximum velocity and Michaelis constant were calculated as 3.171 µM−1·min and 1628.23 µM, respectively. The enzyme was activated by Fe2+, Zn2+, Ca2+ and Cu2+, while Hg2+, Mn2+,... 

    Kinetic studies of Bisphenol A in aqueous solutions by enzymatic treatment

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 2 , 2019 , Pages 821-832 ; 17351472 (ISSN) Ghobadi Nejad, Z ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2019
    Abstract
    Bisphenol A (BPA), which is a major component in the production of various consumer products, is one of the most significant endocrine-disrupting chemicals. In this research, the biocatalytic elimination of Bisphenol A using laccase produced by Phanerochaete chrysosporium was examined and optimized. The response surface methodology was used to study the effect of independent variables such as pH, temperature, initial laccase activity, initial Bisphenol A concentration, and the interactive effects of each variable on the removal of Bisphenol A and residual enzyme activity. Based on response surface plots, the maximum Bisphenol A removal (93%) was detected at a pH value of 8, temperature... 

    Kinetic studies of Bisphenol A in aqueous solutions by enzymatic treatment

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 2 , Febraury , 2018 , Pages 821–832 ; 17351472 (ISSN) Ghobadi Nejad, Z ; Borghei, S. M ; Yaghmaei, S ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2018
    Abstract
    Bisphenol A (BPA), which is a major component in the production of various consumer products, is one of the most significant endocrine-disrupting chemicals. In this research, the biocatalytic elimination of Bisphenol A using laccase produced by Phanerochaete chrysosporium was examined and optimized. The response surface methodology was used to study the effect of independent variables such as pH, temperature, initial laccase activity, initial Bisphenol A concentration, and the interactive effects of each variable on the removal of Bisphenol A and residual enzyme activity. Based on response surface plots, the maximum Bisphenol A removal (93%) was detected at a pH value of 8, temperature 40... 

    Some investigations on protease enzyme production kinetics using bacillus licheniformis BBRC 100053 and effects of inhibitors on protease activity

    , Article International Journal of Chemical Engineering ; 2014 ; ISSN: 1687806X Ghobadi Nejad, Z ; Yaghmaei, S ; Moghadam, N ; Sadeghein, B ; Sharif University of Technology
    2014
    Abstract
    Due to great commercial application of protease, it is necessary to study kinetic characterization of this enzyme in order to improve design of enzymatic reactors. In this study, mathematical modeling of protease enzyme production kinetics which is derived from Bacillus licheniformis BBRC 100053 was studied (at 37°C, pH 10 after 73 h in stationary phase, and 150 rpm). The aim of the present paper was to determine the best kinetic model and kinetic parameters for production of protease and calculating K i (inhibition constant) of different inhibitors to find the most effective one. The kinetic parameters K m (Michaelis-Menten constant) and V m (maximum rate) were calculated 0.626 mM and... 

    Biodegradation of polychlorinated biphenyls by lysinibacillus macrolides and bacillus firmus isolated from contaminated soil

    , Article International Journal of Engineering, Transactions B: Applications ; Volume 32, Issue 5 , 2019 , Pages 628-633 ; 1728144X (ISSN) Samadi, A ; Sharifi, H ; Ghobadi Nejad, Z ; Yaghmaei, S ; Sharif University of Technology
    Materials and Energy Research Center  2019
    Abstract
    Polychlorinated biphenyls (PCBs) cause many significant ecological problems because of their low degradability, high harmfulness, and solid bioaccumulation.Two bacterial strains were isolated from soil that had been polluted with electrical transformer liquid for more than 40 years. The isolates were distinguished as Lysinibacillus macrolides DSM54Tand Bacillus firmus NBRC15306Tthrough 16S rRNA sequencing analysis.This is the primary report of an agent of the genus Bacillus firmus equipped for the removal of PCBs. The strains could develop broadly on 2-Chlorobiphenyl and 2,4-dichlorobiphenyl. GC/MS analysis of individual congeners revealed up to 80% degradation of the xenobiotics in 96h,...