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Synthesis, Characterization and Spectroscopic Studies of Novel Mono and bi Nuclear Zinc(II), Palladium(II) and Cobalt(II) Schiff Base Complexes: Reactivity and Interaction
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
Due to study of reactivity and interaction of Schiff base complexes, as models of biological system such as vitamin B (B6 and B12) and enzyme (cytochtome c oxidase), some mono and binuclear Zn(II), Pd(II) and Co(II) Schiff base complexes were synthesized and characterized. As a model for vitamin B6, tridentate Schiff base ligands derived from the condensation of water soluble aldehyde with the amino acids (glycine, L-alanine, L-valine, L-leucine and L-phenylalanine) in the presence of Zn (OAc)2.2H2O give rise to the formation of five new water soluble Zn(II) complexes. The IR spectra of these complexes show that, there are prominent stretching vibration of the azomethine band (HC=N) at...
Increased Expression of Flagellins Recombinant Soluble form by Chemical Chaperon
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheila (Supervisor) ; Tarahomjoo, Shirin (Supervisor)
Abstract
Flagella is the organelle involved in motility of Salmonella and plays an important role in colonization of Salmonella. Flagellins is the structural subunits of flagellar filament that is known as an adjuvant. Recombinant production of flagellin of S. enteritidis is advantageous due to the removal of pathogenic microorganism from the production process and improved process safety. E.coli is an appropriate host for the expression of recombinant proteins. However, its major obstacle is the formation of inclusion bodies. Inclusion bodies are aggregated inactive proteins and the recovery of proteins in the active form from these aggregates usually has a low yield. Therefore, the objective of our...
Experimental Study of the β-CD-g-PG Hybrid Nanostructure On Phase Solubilityof Hydrophobic Drug
, M.Sc. Thesis Sharif University of Technology ; Saifkordi, Aliakbar (Supervisor) ; Vossoughi, Manouchehr (Supervisor)
Abstract
Some widely used drugs such as paclitaxel (PTX) are poorly water soluble. The clinical use of PTX with solubilizer causes side effects. These problems limited its application in treatments. In this work has been studied the effect of β-CD-g-PG (HPCD) hybrid nanomaterials, conjugated PG branches onto β-CD core, on the water solubility of PTX. First HPCD has been synthesized. Then the inclusion complex of PTX with HPCD was prepared. The inclusion complex efficiency for PTX:HPCD complex in 1:25 mole ratio was 87%. Then solubility of PTX with HPCD in water has been determined, showing Ap type phase solubility diagram. Then stability constants were calculated. The first order and second order...
Investigation of phase Solubility Enhancement of Paclitaxel by Inclusion Complex of drug in B-CD-g-PG
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor) ; Vossoughi, Manoochehr (Supervisor) ; Kazemi Daliri, Akhtarolmoluk (Supervisor)
Abstract
Paclitaxel is using as a drug against breast and ovary cancers. Although paclitaxel has high biologic activity, it has very poor solubility in water the same as some other drugs. Since drugs should be solved in water to be absorbed by the body, for absorb enhancement, we should use carriers which includes both polar and non polar sites.
Beta-Cyclodextrin which has this feature is capable for producing inclusion complex in its hydrophobic pores with non polar materials. In this project, by adding polymeric polyglycerol branches on Beta-Cyclodextrin, a polymeric nanostructure has been developed to enhance water solubility in comparison with pure Beta-Cyclodextrin.
Study on producing...
Beta-Cyclodextrin which has this feature is capable for producing inclusion complex in its hydrophobic pores with non polar materials. In this project, by adding polymeric polyglycerol branches on Beta-Cyclodextrin, a polymeric nanostructure has been developed to enhance water solubility in comparison with pure Beta-Cyclodextrin.
Study on producing...
Design and Synthesis of a Novel Nanomaterial as a Carrier of a Hydrophobe drug in an Inclusion Complex based on Cychlodextrin
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Kazemi, Akhtarolmolouk (Supervisor)
Abstract
Paclitaxel is used as a drug against breast and ovarian cancers. Although paclitaxel has high biologic activity, it has very pour solubility in water like some other drugs. Since drugs should be solved in water to be absorbed by the body, for absorb enhancement, we should use carriers which includes both polar and non polar sites. eta-Cyclodextrin which has this feature is capable for producing inclusion complex in its hydrophobic pores with non polar materials. In this project by adding polymeric polyacrylamide branches on beta-Cyclodextrin, polymeric nano structure has been developed to enhance water solubility in comparison with pure beta-Cyclodextrin. Study on producing polymeric nano...
Application and performance comparison of high-resolution central schemes for the black oil model
, Article International Journal of Numerical Methods for Heat and Fluid Flow ; Volume 17, Issue 7 , 2007 , Pages 736-753 ; 09615539 (ISSN) ; Taghizadeh Manzari, M ; Kazemzadeh Hannani, S ; Sharif University of Technology
2007
Abstract
Purpose - The purpose of this paper is to investigate the performance of a specific class of high-resolution central schemes in conjunction with the black oil models for hydrocarbon reservoir simulation. Design/methodology/approach - A generalized black oil model is adopted, in which the solubility of gas in both oil and water and evaporation of oil are considered, leading to a system of equations prone to degeneracy. A computer code is generated and three test cases are solved to evaluate the performance of various schemes in terms of accuracy and discontinuity handling. Findings - It is shown that, although some of the central schemes are highly sensitive to the choice of...
Correlation and prediction the activity coefficients and solubility of amino acids and simple peptide in aqueous solution using the modified local composition model
, Article Fluid Phase Equilibria ; Volume 255, Issue 2 , 2007 , Pages 160-166 ; 03783812 (ISSN) ; Taghikhani, V ; Vossoughi, M ; Sharif University of Technology
2007
Abstract
In this work, the modified Wilson model was used to obtain the activity coefficients of amino acids and simple peptides in non-electrolyte aqueous solutions. The Wilson model was modified using the new local mole fraction proposed by Zhao et al. and non-random case for the reference state. The binary interaction parameters (BIP) of the modified Wilson model for amino acid-water pairs were obtained using the experimental data of the activity coefficients for amino acids available in the literature. The modified Wilson model was also used to correlate the solubility of amino acids in water and the values of Δh/R, Δs/R, and Δg/R of the solutions studied were reported. The results obtained...
Solubilities of acetaminophen in supercritical carbon dioxide with and without menthol cosolvent: Measurement and correlation
, Article Scientia Iranica ; Volume 19, Issue 3 , June , 2012 , Pages 619-625 ; 10263098 (ISSN) ; Ghotbi, C ; Dorkoosh, F ; Striolo, A ; Sharif University of Technology
2012
Abstract
The solubility of acetaminophen in SuperCritical-Carbon Dioxide (SC- CO 2) with and without menthol as a cosolvent was measured at various temperatures (313, 328 and 343) K, and within pressures ranging from (10 to 25) MPa. It should be stated that the cosolvent, menthol, has chiral isomers with different melting points. Therefore, the effects of both menthol (I) with a lower melting point and menthol (II) with a higher melting point, as cosolvents on the solubility of acetaminophen in SC- CO 2, were studied. The experimental data collected in this work were obtained using a static flow apparatus. The experiments were replicated at least three times and the data reported are the average of...
Rigorous silica solubility estimation in superheated steam: Smart modeling and comparative study
, Article Environmental Progress and Sustainable Energy ; Volume 38, Issue 4 , 2019 ; 19447442 (ISSN) ; Shokrollahi, A ; Esmaeili Jaghdan, Z ; Ghazanfari, M. H ; Sharif University of Technology
John Wiley and Sons Inc
2019
Abstract
One of the main issues of wastewater treatment is the silica deposition in steam turbines. Evaporation of silica with the steam in adequate concentration is one of the main sources of scale formation in steam turbines. In this study, the authors introduce the utilization of a genetic-based approach—gene expression programming (GEP)—for solubility prognostication of the silica in superheated steam of boilers with respect to water silica content and pressure. The result of GEP mathematical approach is a new algebraic formula to achieve our goals. Developed model predicts the silica solubility in the range of 0.8–22.1 MPa and 1–500 mg/kg for pressure and boiler water silica content,...
Maximal Subgroups of
, M.Sc. Thesis Sharif University of Technology ; Mahdavi Hezavehi, Mohammad (Supervisor)
Abstract
In this thesis we study the structure of locally solvable, solvable, locally nilpotent, and nilpotent maximal subgroups of skew linear groups. In [5] it has been conjectured that if D is a division ring and M a nilpotent maximal subgroup of , then D is commutative. In connection with this conjecture we show that if M a nilpotent maximal subgroup of , then M is an abelian group. Also we show that is a solvable maximal subgroup of real quaternions and so give a counterexample to Conjecture 3 of [5], which states that if D is a division ring and M a solvable maximal subgroup of , then D is commutative. Also we completely determine the structure of division rings with a non-abelian...
Investigation of Membrane Fouling in Submerged Membrane Electro-Bioreactor (SMEBR) with Iron Electrodes
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Manoochehr (Supervisor)
Abstract
This thesis presents the results of the performance of a novel technology called submerged membrane electro-bioreactor (SMEBR). The SMEBR treats wastewater by combining membrane filtration, electrokinetic phenomena, and biological processes in one reactor, and improves treatment performance while helping to control membrane fouling. The newly designed SMEBR system was based on applying an intermittent direct current (DC) field between immersed perforated electrodes around a membrane filtration module. The SMEBR system significantly reduced the fouling rate when iron worked as electrodes and an intermittent DC with an operational different mode was applied.
In Phase 1 of this project,...
In Phase 1 of this project,...
Synthesis and Characterization of Cis-dioxomolybdenum(VI) Complex with an ONOtype Tridentate Schiff base Ligand and its Application as a Catalyst for Epoxidation of Olefinsin Water
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
New dioxomolybdenum(VI) complex has been synthesized by reacting N-hydroxyphenyl-[5-(triphenylphosphonium)methyl]salicylideneamine chloride (PPh3-H2sap) as a water soluble ligand and [MoO2(acac)2] in ethanolic solution. The water soluble ligand (PPh3-H2sap) was prepared by reaction of 2-aminophenol with (3-formyl-4-hydroxybenzyl)triphenylphosphonium chloride as a water solublesalicylaldehyde derivative. The resulting complex with the formula [MoO2(PPh3-H2sap)(EtOH)] which contains an ethanol molecule in sixth site of coordination, was characterized by elemental analyses, 1H NMR,31P NMR, IR and UV-Vis spectroscopic studies. This complex was tested as a catalyst for the homogeneous...
Characterization of Protein Content in Soluble Microbial Products Involved in Fouling of Membrane Bioreactor
, M.Sc. Thesis Sharif University of Technology ; Torkian, Ayoub (Supervisor) ; Mousavi, Reza (Supervisor)
Abstract
Membrane bioreactors are increasingly being used for treatment of domestic and industrial effluents. A major operational drawback of this system is membrane fouling attributed to soluble microbial products (SMPs). In this study sampling were taken from microbial products on the surface and within the membrane pores and mixed liquir for mass characterization of protein content. Water-washing was used for surface and reversible portion of pore samples. Chemical wash with urea was used for further cleansing of SMPs within the pores. All samples were concentrate by precipitation with ammonium sulfate salt prior to analysis. Total protein content of samples was measured by lowry method. SDS-PAGE...
The gas-oil interfacial behavior during gas injection into an asphaltenic oil reservoir
, Article Journal of Chemical and Engineering Data ; Volume 58, Issue 9 , 2013 , Pages 2513-2526 ; 00219568 (ISSN) ; Mehranbod, N ; Ayatollahi, S ; Sharif University of Technology
2013
Abstract
Oil displacement and recovery efficiency during gas injection depends on the competition between driving forces and capillary resistance that is governed by gas-oil interfacial behavior. Detailed study of the interfacial forces during gas injection is the main objective of this research work. The effects of injecting gas composition and the possibility of asphaltene precipitation in a wide pressure range were determined through comprehensive experimental study. This was performed by measurement of interfacial tension of a highly asphaltenic Iranian crude oil in three surrounding gas mediums. The results showed that as pressure increases, the rate to reach miscibility reduces in the vicinity...
Modeling of CO2 solubility in brine by using neural networks
, Article Saint Petersburg 2012 - Geosciences: Making the Most of the Earth's Resources, 2 April 2012 through 5 April 2012 ; April , 2012 ; Salami, H ; Taghikhani, V ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
CO2 sequestration in geological formations, such as aquifers, is known to be the best short-term solution to CO2 mitigation. Accurate description of CO2 solubility in brine is important for evaluating the capacity of aquifers to sequester CO2. Currently, EOS-based models are widely used in reservoir compositional simulators for this purpose. However, most of these models involve complex and iterative calculations which take too much time in case of large-scale flow simulation of geological CO2 storage. In this study, a neural network model is presented for prediction of CO2 solubility in brine which is highly accurate with less computational overhead
Experimental investigation of near miscibility effect on relative permeability curves
, Article 74th European Association of Geoscientists and Engineers Conference and Exhibition 2012 Incorporating SPE EUROPEC 2012: Responsibly Securing Natural Resources, 4 June 2012 through 7 June 2012 ; June , 2012 , Pages 5469-5474 ; 9781629937908 (ISBN) ; Masihi, M ; Ghazanfari, M. H ; Sharif University of Technology
European Association of Geoscientists and Engineers, EAGE
2012
Abstract
The requirement of reliable relative permeability data is more intensified when the miscibility condition approaches. In this work the relative permeability of CO2 and oil has been measured at different miscibility conditions using conventional methods. Fractured dolomite and sandstone core plugs samples were used in the experiments. Due to some errorful assumptions of conventional methods such as immiscible, incompressible displacement, inverse modeling was used for predicting the reliable relative permeability of oil and gas phases at near miscible condition from measured oil production and pressure drop data. The initial guesses of relative permeabilities were provided from conventional...
Correlation and prediction of solubility of CO2 in amine aqueous solutions
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 29, Issue 1 , 2010 , Pages 111-124 ; 10219986 (ISSN) ; Taghikhani, V ; Ghotbi, C ; Safekordi, A. A ; Najibi, H ; Sharif University of Technology
Abstract
The solubility of CO2 in the primary, secondary, tertiary and sterically hindered amine aqueous solutions at various conditions was studied. In the present work, the Modified Kent-Eisenberg (M-KE), the Extended Debye-Hückel (E-DH) and the Pitzer models were employed to study the solubility of CO2 in amine aqueous solutions. Two explicit equations are presented to evaluate the concentration of H+ as well as the equilibrium constants of protonation reactions for the tertiary and sterically hindered amine aqueous solutions. Using the M-KE model, the equilibrium constants of protonation reactions of amines were correlated in terms of temperature, CO2 partial pressure and amine concentration....
Curcumin-loaded amine-functionalized mesoporous silica nanoparticles inhibit α-synuclein fibrillation and reduce its cytotoxicity-associated effects
, Article Langmuir ; Volume 32, Issue 50 , 2016 , Pages 13394-13402 ; 07437463 (ISSN) ; Morshedi, D ; Yaghmaei, S ; Aliakbari, F ; Rahimi, F ; Arpanaei, A ; Sharif University of Technology
American Chemical Society
2016
Abstract
This study aimed to develop a drug carrier based on amine-functionalized mesoporous silica nanoparticles (AAS-MSNPs) for a poorly water-soluble drug, curcumin (CUR), and to study its effects on α-synuclein (α-Syn) fibrillation and cytotoxicity. Here, we show that AAS-MSNPs possess high values of loading efficiency and capacity (33.5% and 0.45 mg drug/mg MSNPs, respectively) for CUR. It is also revealed that α-Syn species interact strongly with the CUR-loaded AAS-MSNPs, leading to a significant inhibition of the fibrillation process. Furthermore, these samples reduce the toxic effects of CUR. However, drug-loaded AAS-MSNPs do not affect the cytotoxic properties of the formed fibrils...
Modeling of asphaltene precipitation in calculation of minimum miscibility pressure
, Article Industrial and Engineering Chemistry Research ; Volume 56, Issue 25 , 2017 , Pages 7375-7383 ; 08885885 (ISSN) ; Saeedi Dehaghani, A. H ; Sharif University of Technology
American Chemical Society
2017
Abstract
An algorithm has been developed to investigate the effect of asphaltene precipitation on calculation of minimum miscibility pressure (MMP), which is one of the key design parameters of any gas injection projects. In fact, this algorithm is the extension of procedure suggested by Jaubert et al. for prediction of MMP whatever the displacement mechanism. The vapor-liquid equilibrium calculation and then liquid-liquid equilibrium calculation are required to be taken account to estimate the amount of asphaltene precipitation. The association equation of state (AEOS) has been applied to determine the phase behavior of asphaltene. The algorithm has been used for the MMP prediction of Weyburn...
Theoretical investigation of the enhanced solubility of perfluorobenzene in the supercritical carbon dioxide as a function of temperature and density by Monte Carlo simulation
, Article Chemical Physics Letters ; Volume 444, Issue 1-3 , 2007 , Pages 48-55 ; 00092614 (ISSN) ; Khanlarkhani, A ; Sharif University of Technology
2007
Abstract
The absolute free energy of solvation of benzene and perfluorobenzene was measured in supercritical carbon dioxide using the expanded-ensemble method in the context of Monte Carlo (MC) Simulations. The MC calculations were carried out at 12 state points on the solvent phase diagram: (ρr = 0.5, 1.0, 1.5, 2.0; Tr = 1.01, 1.10, and 1.20). These conditions were chosen to address the accurance of specific molecular interactions between CO2 and fluorine. The greater stability of perfluorobenzene observed over all states investigated in this study attributed to the greater solvent accessible surface area and 25-30% increase in the strength of the interaction of this molecule with CO2 in the...