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Bimodal electricity generation and aromatic compounds removal from purified terephthalic acid plant wastewater in a microbial fuel cell
, Article Biotechnology Letters ; Volume 35, Issue 2 , 2013 , Pages 197-203 ; 01415492 (ISSN) ; Kariminia, H. R ; Savizi, I. S. P ; Sharif University of Technology
2013
Abstract
Wastewater of purified terephthalic acid (PTA) from a petrochemical plant was examined in a membrane-less single chamber microbial fuel cell for the first time. Time course of voltage during the cell operation cycle had two steady phases, which refers to the fact that metabolism of microorganisms was shifted from highly to less biodegradable carbon sources. The produced power density was 31.8 mW m-2 (normalized per cathode area) and the calculated coulombic efficiency was 2.05 % for a COD removal of 74 % during 21 days. The total removal rate of different pollutants in the PTA wastewater was observed in the following order: (acetic acid) > (benzoic acid) > (phthalic acid) > (terephthalic...
Self-assembly of dandelion-like hydroxyapatite nanostructures via hydrothermal method
, Article Journal of the American Ceramic Society ; Volume 91, Issue 10 , 2008 , Pages 3292-3297 ; 00027820 (ISSN) ; Mazloumi, M ; Mohajerani, M ; Kajbafvala, A ; Zanganeh, S ; Arami, H ; Sadrnezhaad, S. K ; Sharif University of Technology
2008
Abstract
Self-assembled dandelion-like hydroxyapatite (HAp) nanostructures were successfully synthesized via a mild template-free hydrothermal process, using ethylenediaminetetraacetic acid (EDTA) as the surfactant. The obtained dandelion-like HAp nanostructures were between 5 and 8 μm in diameter and were composed of radially oriented nanorods with an average diameter of about 200 nm. The X-ray diffraction analysis and Fourier transform infrared spectroscopy were used to characterize the crystalline phase and purity of the synthesized nanostructures. The Brunauer-Emmett-Teller surface area of the dandelion-like nanostructures was measured to be about 39 m2/g. The results of thermal analysis revealed...
Study of droplet behaviour along a pulsed liquid-liquid extraction column in the presence of nanoparticles
, Article Canadian Journal of Chemical Engineering ; Volume 91, Issue 3 , 2013 , Pages 506-515 ; 00084034 (ISSN) ; Bahmanyar, A ; Molavi, H ; Bastani, D ; Mozdianfard, M. R ; Bahmanyar, H ; Sharif University of Technology
2013
Abstract
In this article, droplet size and its distribution along a pulsed liquid-liquid extraction column, is studied where SiO2 nanoparticles with concentrations of 0.01, 0.05 and 0.1vol.% and different hydrophobicities are applied to the dispersed phase. Using ultrasonication, nanoparticles were dispersed in kerosene as the base fluid. Nanofluids' stability was ensured using a UV-vis spectrophotometer. Some 22,000 droplets were measured by photographic technique and results were compared with systems containing no-nanoparticles (Water-Acetic acid-Kerosene). Addition of nanoparticles changed the droplet shape from ellipsoidal to spherical. Also, there was a marked influence on droplet breakage and...
Minimizing CO2 formation in Ir-catalyzed methanol carbonylation process
, Article 20th International Congress of Chemical and Process Engineering, CHISA 2012, Prague, 25 August 2012 through 29 August 2012 ; 2012 , Pages 1179-1188 ; 18777058 (ISSN) ; Hosseinpour, V ; Sharif University of Technology
2012
Abstract
Acetic acid is one of the most important petrochemical products. Carbonylation of methanol in homogenous phase is one of the major routes for production of acetic acid. Amongst group VIII metal catalysts used in this process iridium has displayed the best capabilities. To investigate effect of operating parameters like: temperature, pressure, methyl iodide, methyl acetate, iridium, ruthenium, and water concentrations on the carbon dioxide formation, experimental design for this system based upon central composite design (CCD) was utilized. Statistical carbon dioxide formation equation developed by this method contained individual, interactions and curvature effects of parameters on the...
A combined model for large scale batch culture MFC-digester with various wastewaters through different populations
, Article Bioelectrochemistry ; Volume 106 , December , 2015 , Pages 298-307 ; 15675394 (ISSN) ; Yaghmaei, S ; Mardanpour, M. M ; Sharif University of Technology
Elsevier
2015
Abstract
In this study, a new model of microbial fuel cell (MFC) was obtained for the first time. The modeled MFC was made using a combination of two approaches; the conduction-based method and two-step anaerobic digestion. Performance of the MFC was based on calculations for current evolution and polarization curves with different subsequent variables of the biofilm and anolyte. The model was able to make predictions for performance of the MFC for a simple substrate to more complex ones. The model was successfully validated with a variety of substrates (acetate, glucose and dairy wastewater) and the results were compared with previously published measurements. The model polarization results showed...
Green products from herbal medicine wastes by subcritical water treatment
, Article Journal of Hazardous Materials ; Volume 424 , 2022 ; 03043894 (ISSN) ; Tavakoli, O ; Sarkhanpour, R ; Sajadi, S. M ; Zarrintaj, P ; Rabiee, N ; Akhavan, O ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Herbal medicine wastes (HMWs) are byproducts of medicine factories, which are mainly landfilled for their environmental problems. Only bearing in mind the contamination and concerns caused by the COVID-19 pandemic and environmental emissions, the worth of herbal medicine wastes management and conversion to green products can be understood. In this work, subcritical water treatment was carried out batch-wise in a stainless tube reactor in the pressure range of 0.792–30.0 MPa, varying the temperature (127–327 °C) and time (1–60 min) of extraction. This resulted in new and green material sources, including organic acids, amino acids, and sugars. Amazingly, at very low extraction times (below 5...
QSAR study of heparanase inhibitors activity using artificial neural networks and Levenberg-Marquardt algorithm
, Article European Journal of Medicinal Chemistry ; Volume 43, Issue 3 , 2008 , Pages 548-556 ; 02235234 (ISSN) ; Asadollahi Baboli, M ; Shahbazikhah, P ; Sharif University of Technology
2008
Abstract
A linear and non-linear quantitative structure-activity relationship (QSAR) study is presented for modeling and predicting heparanase inhibitors' activity. A data set that consisted of 92 derivatives of 2,3-dihydro-1,3-dioxo-1H-isoindole-5-carboxylic acid, furanyl-1,3-thiazol-2-yl and benzoxazol-5-yl acetic acids is used in this study. Among a large number of descriptors, four parameters classified as physico-chemical, topological and electronic indices are chosen using stepwise multiple regression technique. The artificial neural networks (ANNs) model shows superiority over the multiple linear regressions (MLR) by accounting 87.9% of the variances of antiviral potency of the heparanase...
Simulation of methanol carbonylation reactor in acetic acid production plant: selection of an appropriate correlation for mass transfer coefficients
, Article International Journal of Chemical Reactor Engineering ; Volume 17, Issue 4 , 2019 ; 15426580 (ISSN) ; Tourani, S ; Khorasheh, F ; Sharif University of Technology
De Gruyter
2019
Abstract
This paper deals with mathematical modeling and simulation of methanol carbonylation reactor in acetic acid production plant that consisted of a continuous stirred tank reactor (CSTR), a flash drum, a Joule-Thomson valve, and a condenser. The model was based on material and energy balances that considered liquid-gas mass transfer, thermodynamics, and reactor hydrodynamics. The most important aspect of the model was the selection of an appropriate correlation for prediction of mass transfer coefficient. Several correlations were examined and comparison of the model results with plant data indicated that the correlation reported by Lemoine was most appropriate. The simulation results were...
An experimental design approach to determine effects of the operating parameters on the rate of Ru promoted Ir carbonylation of methanol
, Article World Academy of Science, Engineering and Technology ; Volume 73 , March , 2011 , Pages 598-603 ; 2010376X (ISSN) ; Kazemini, M ; Mohammadrezaee, A ; Sharif University of Technology
Abstract
carbonylation of methanol in homogenous phase is one of the major routesfor production of acetic acid. Amongst group VIII metal catalysts used in this process iridium has displayed the best capabilities. To investigate effect of operating parameters like: temperature, pressure, methyl iodide, methyl acetate, iridium, ruthenium, and water concentrations on the reaction rate, experimental design for this system based upon central composite design (CCD) was utilized. Statistical rate equation developed by this method contained individual, interactions and curvature effects of parameters on the reaction rate. The model with p-value less than 0.0001 and R 2 values greater than 0.9; confirmeda...
A study of the water-gas shift reaction in Ru-promoted Ir-catalysed methanol carbonylation utilising experimental design methodology
, Article Chemical Engineering Science ; Volume 66, Issue 20 , October , 2011 , Pages 4798-4806 ; 00092509 (ISSN) ; Kazemeini, M ; Mohammadrezaee, A ; Sharif University of Technology
2011
Abstract
The water-gas shift reaction occurs competitively to the main reaction of the Ir-catalysed methanol carbonylation process. To study the effect of seven factors including temperature, pressure, iridium, ruthenium, methyl iodide, methyl acetate and water concentrations on the formation of hydrogen and carbon dioxide as a result of the water-gas shift reaction and other side reactions in the carbonylation of methanol to acetic acid, the experimental design method combined with response surface methodology (RSM) was utilised. Central composite design at five levels (with α=1.63) was used to design experiments. A quadratic model that included the main and interaction effects of variables for H 2...
Optimisation of Ru-promoted Ir-catalysed methanol carbonylation utilising response surface methodology
, Article Applied Catalysis A: General ; Volume 394, Issue 1-2 , February , 2011 , Pages 166-175 ; 0926860X (ISSN) ; Kazemeini, M ; Mohammadrezaee, A ; Sharif University of Technology
2011
Abstract
In this study, central composite design (CCD) at five levels (-1.63, -1, 0, +1, +1.63) combined with response surface methodology (RSM) have been applied to optimise methanol carbonylation using a ruthenium-promoted iridium catalyst in a homogenous phase. The effect of seven process variables, including temperature, pressure, iridium, ruthenium, methyl iodide, methyl acetate and water concentrations, as well as their binary interactions, were modelled. The determined R 2 values greater than 0.9 for the rate and methane formation data confirmed that the quadratic equation properly fitted the obtained experimental data. The optimum conditions for maximum rate and minimum methane formation were...
Investigation the effect of super hydrophobic titania nanoparticles on the mass transfer performance of single drop liquid-liquid extraction process
, Article Separation and Purification Technology ; Volume 176 , 2017 , Pages 107-119 ; 13835866 (ISSN) ; Bastani, D ; Najafi, F ; Sharif University of Technology
Abstract
Hydrophobic titania nanoparticles were synthesized by a novel in situ sol-gel method and applied in a single drop liquid-liquid extraction column to enhance the overall dispersed-phase mass transfer coefficient (Kod). The chemical system of toluene, acetic acid and water was used, and the direction of solute (acetic acid) mass transfer was from dispersed phase, including: toluene and acetic acid to the continuous phase of water. For such system, much of the mass transfer resistance exists in the dispersed phase, which is nonpolar organic liquid. Hence, modified titania nanoparticles (MTNP's), prepared by sol-gel route, in five different concentrations of 0.001–0.005 wt.% were added in the...
Investigation of the impact of synthesized hydrophobic magnetite nanoparticles on mass transfer and hydrodynamics of stagnant and stirred liquid–liquid extraction systems
, Article Chemical Engineering Research and Design ; Volume 147 , 2019 , Pages 305-318 ; 02638762 (ISSN) ; Azizi, Z ; Bastani, D ; Sharif University of Technology
Institution of Chemical Engineers
2019
Abstract
The impact of modified magnetite nanoparticles (MMNPs)on hydrodynamics and mass transfer in liquid–liquid extraction process was assessed using a ternary chemical system of toluene-acetic acid–water. The organic phase which contained toluene and acetic acid was dispersed through water, and the mass transfer of acetic acid between two phases was investigated. The hydrophobic modified magnetite nanoparticles (MMNPs)prepared through an optimized in-situ method were added to the dispersed phase at different concentrations (0.001−0.005 wt%). Two separate conditions were provided in the experiments, i.e. stagnant and stirred continuous phase. The latter case was provided by a rotor at two...
Metabolomics analysis of the saliva in patients with chronic hepatitis b using nuclear magnetic resonance: A pilot study
, Article Iranian Journal of Basic Medical Sciences ; Volume 22, Issue 9 , 2019 , Pages 1044-1049 ; 20083866 (ISSN) ; Mohamadkhani, A ; Chashmniam, S ; Shahnazari, P ; Amini, M ; Arjmand, B ; Malekzadeh, R ; Nobakht Motlagh Ghoochani, B. F ; Sharif University of Technology
Mashhad University of Medical Sciences
2019
Abstract
Objective(s): Hepatitis B virus infection causes chronic disease such as cirrhosis and hepatocellular carcinoma. The metabolomics investigations have been demonstrated to be related to pathophysiologic mechanisms in many disorders such as hepatitis B infection. The aim of this study was to investigate the saliva metabolic profile of patients with chronic hepatitis B infection and to identify underlying mechanisms as well as potential biomarkers associated with the disease. Materials and Methods: Saliva from 16 healthy subjects and 20 patients with chronic hepatitis B virus were analyzed by nuclear magnetic resonance (NMR). Then, multivariate statistical analysis was performed to identify...
Synthesis and characterization of TiO2-graphene nanocomposites modified with noble metals as a photocatalyst for degradation of pollutants
, Article Applied Catalysis A: General ; Vol. 462–463 , July , 2013 , Pages 82–90 ; Esfandiarb, A. (Ali) ; Rahman Setayesha, S. (Shahrbano) ; Habibi-Yangjehc, A. (Aziz) ; Iraji zadb, A. (Azam) ; Gholamia, M .R. (Mohammad Reza) ; Sharif University of Technology
Abstract
TiO2–graphene (TiO2–GR) nanocomposites were synthesized using photocatalytic reduction method. TiO2–GR nanocomposites were thereafter doped with noble metals (Pt and Pd) by chemical reduction of the corresponding cations. The samples were characterized by different techniques. The addition of GR to TiO2 decreases the crystalline size of TiO2 due to the homogeneous dispersion of the TiO2 nanoparticles on GR sheets and prevention of coagulation of TiO2 nanoparticles during synthesis process. In addition, the surface area of TiO2 was increased by addition of GR and deposition of noble metals which helps to prevent agglomeration of graphene sheets and TiO2 nanoparticles. Red shifts to the higher...
Synthesis and characterization of TiO2-graphene nanocomposites modified with noble metals as a photocatalyst for degradation of pollutants
, Article Applied Catalysis A: General ; Volume 462-463 , 2013 , Pages 82-90 ; 0926860X (ISSN) ; Esfandiar, A ; Rahman Setayesh, S ; Habibi Yangjeh, A ; Iraji Zad, A ; Gholami, M. R ; Sharif University of Technology
2013
Abstract
TiO2-graphene (TiO2-GR) nanocomposites were synthesized using photocatalytic reduction method. TiO2-GR nanocomposites were thereafter doped with noble metals (Pt and Pd) by chemical reduction of the corresponding cations. The samples were characterized by different techniques. The addition of GR to TiO2 decreases the crystalline size of TiO2 due to the homogeneous dispersion of the TiO2 nanoparticles on GR sheets and prevention of coagulation of TiO2 nanoparticles during synthesis process. In addition, the surface area of TiO2 was increased by addition of GR and deposition of noble metals which helps to prevent agglomeration of graphene sheets and TiO 2 nanoparticles. Red shifts to the...
A metabonomics study on crohn's disease using nuclear magnetic resonance spectroscopy
, Article HealthMED ; Volume 6, Issue 11 , July , 2012 , Pages 3577-3583 ; 18402291 (ISSN) ; Kyani, A ; Nejad, M. R ; Rezaye Tavirani, M ; Naderi, N ; Zali, M. R ; Tafazzoli, M ; Oskouie, A. A ; Sharif University of Technology
2012
Abstract
Objective: Crohn's disease (CD) is one the important illnesses can affect any part of the gastrointestinal tract. CD is not easily diagnosed using the clinical tests. Thus, the discovery of proper methods would be a major step towards CD diagnosis. The aim of this study was to seek the metabolic biomarkers causes of CD compare to control group. Materials and Methods: In present study, we employed metabolic profiling using proton nuclear magnetic resonance spectroscopy (1HNMR) to find metabolites in serum which are helpful for the diagnosis of CD. Classification of CD and healthy subject was done using classification and regression trees (CART). The metabolites that caused changes in people...
Ternary composite of TiO2 nanotubes/Ti plates modified by g-C3N4 and SnO2 with enhanced photocatalytic activity for enhancing antibacterial and photocatalytic activity
, Article Journal of Photochemistry and Photobiology B: Biology ; Volume 178 , 2018 , Pages 124-132 ; 10111344 (ISSN) ; Mohaghegh, N ; Abedini, A ; Sharif University of Technology
Elsevier B.V
2018
Abstract
A series of g-C3N4-SnO2/TiO2 nanotubes/Ti plates were fabricated via simple dipping of TiO2 nanotubes/Ti in a solution containing SnCl2 and g-C3N4 nanosheets and finally annealing of the plates. Synthesized plates were characterized by various techniques. The SEM analysis revealed that the g-C3N4-SnO2 nanosheets with high physical stability have been successfully deposited onto the surface of TiO2 nanotubes/Ti plate. Photocatalytic activity was investigated using two probe chemical reactions: oxidative decomposition of acetic acid and oxidation of 2-propanol under irradiation. Antibacterial activities for Escherichia coli (E. coli) bacteria were also investigated in dark and under UV/Vis...
Kinetic study of catalytic hydrolysis reaction of methyl acetate to acetic acid and methanol
, Article Iranian Journal of Science and Technology, Transaction B: Engineering ; Volume 30, Issue 5 , 2006 , Pages 595-606 ; 03601307 (ISSN) ; Rahimi, N ; Eftekhari, A. A ; Nasr, M. J ; Sharif University of Technology
2006
Abstract
The reaction kinetics and chemical equilibrium of the reversible catalytic hydrolysis reaction of a methyl acetate to acetic acid and methanol using a strongly acidic ion exchange resin catalyst named Amberlyst 15 were studied. To investigate the different behavior of Amberlyst 15 in the adsorption of reactants and product species, the equilibrium behavior of binary non-reactive liquid mixtures, consisting of one reactant and one product were studied experimentally. The Langmuir model was used to describe the equilibrium condition, quantitatively. Then the employed model was compared with the more complicated thermodynamic models to describe the equilibrium between the catalytic polymer...
Multicomponent nanoparticles as means to improve anaerobic digestion performance
, Article Chemosphere ; Volume 283 , 2021 ; 00456535 (ISSN) ; Ghofrani Isfahani, P ; Tsapekos, P ; Alvarado Morales, M ; Shahrokhi, M ; Angelidaki, I ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Sufficient quantity of trace metals is essential for a well performing anaerobic digestion (AD) process. Among the essential trace elements in active sites of multiple important enzymes for AD are iron and nickel ions. In the present study, iron and nickel in the form of Fe2O3 and NiO were coated on TiO2 nanoparticles to be used in batch and continuous operation mode. The effect of TiO2, Fe2O3–TiO2, and NiO–TiO2 nanoparticles on each step of AD process was assessed utilizing simple substrates (i.e. cellulose, glucose, acetic acid, and mixture of H2–CO2) as well as complex ones (i.e. municipal biopulp). The hydrolysis rate of cellulose substrate increased with higher dosages of the coated...