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khodadadi-moghaddam--mohammad
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Preparation of Titania based solid strong acid and study of its catalytic activity in esterification of Phthalic anhydride and Sebacic acid
, Article Materials Letters ; Volume 60, Issue 6 , 2006 , Pages 715-719 ; 0167577X (ISSN) ; Gholami, M. R ; Sharif University of Technology
2006
Abstract
Esterification of Phthalic anhydride with 2-Octanol and Sebacic acid with Ethanol has been studied in the presence of Sulfated Titania. This study showed that Sulfated Titania has strong catalytic effect on esterification reactions. The effect of some factors such as reaction temperature, molar ratio of acid to alcohol, amount of catalyst used, reaction time, calcination temperature, drying temperature and calcination atmosphere has been investigated. Equilibrium composition achieved in 80 min for Diethyl Sebacate and 20 min for Dioctyl Phthalate in various conditions. © 2005 Elsevier B.V. All rights reserved
The synthesis of multiphasic ionic liquid-coated Pt/Al2O3 catalysts: the selective synchronous hydrogenation of C=C and C=O bonds and the modeling of the ionic liquid and solvent effects
, Article Catalysis Science & Technology ; Issue 2, 2014 , Oct , 2013 , pages 447-455 ; Tasviri, M. (Mahboubeh) ; Khodadadi-moghaddam, M. (Mohammad) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2013
Abstract
Various ionic liquids (ILs) and their mixtures were coated on the Pt/Al2O3 catalyst and the resulting IL-coated catalysts were used in the synchronous hydrogenation of cyclohexene and acetone. The rate constant (k) and selectivity (S) toward CO hydrogenation were determined for several catalysts in various solvents. The solvatochromic parameters (ETN, normalized polarity parameter; π*, dipolarity-polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) were determined for the used ILs and solvents and the obtained selectivities were modeled based on the solvatochromic parameters of the IL layer and bulk solvent while using the Multiparameter Linear Regression (MLR)...
Solvent effects on the reaction rate and selectivity of synchronous heterogeneous hydrogenation of cyclohexene and acetone in ionic liquid/alcohols mixtures
, Article Journal of Molecular Catalysis A: Chemical ; Volume 306, Issues 1–2 , July , 2009 , Pages 11–16 ; Habibi-Yangjeh, A. (Aziz) ; Gholamia, M. R. (Mohamad Reza) ; Sharif University of Tecnology
2009
Abstract
Synchronous heterogeneous catalytic hydrogenation of cyclohexene and acetone, catalyzed by Pt/Al2O3, was carried out in solutions of 2-hydroxy ethylammonium formate (a room temperature ionic liquid, RTIL) with ethanol and propan-1-ol at 25 °C. Rate constants and selectivity of the reaction (relative to cyclohexene hydrogenation) increase with mole fraction of the ionic liquid (IL). The reactants tendency to the catalyst surface increases by addition of the ionic liquid and thus the reaction rate increases, especially for cyclohexene hydrogenation. Consequently the selectivity to cyclohexene hydrogenation was increased. Single-parameter correlations of log kvs.π* (dipolarity/polarizibility)...
Preferential solvation and behavior of solvatochromic indicators in mixtures of an ionic liquid with some molecular solvents
, Article The Journal of Physical Chemistry B ; vol.114 (29) , July , 2010 , pp 9586–9593 ; Khodadadi-Moghaddam, M.(Mohammad) ; Harifi-Mood, A. R. (Ali Reza) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
2010
Abstract
Structural and intermolecular interactions of solvatochromic probes 4-nitroaniline, 4-nitroanisole, and Reichardt’s dye were investigated in the binary mixtures of 2-hydroxy ethylammonium formate as an ionic liquid with N,N-dimethyl formamide, dimethyl amine, and dimethyl sulfoxide. Solvatochromic parameters (ETN, normalized polarity parameter; π*, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen -bond donor acidity) were determined in ionic liquid mixtures at 25 °C using UV−vis spectroscopy. ETN parameters obtained from absorbance of Reichardt’s dye within various mixtures of ionic liquid were observed to be higher than predicted values from ideal additive...
The Role of Safety Attitudes and Attitudes Toward Vehicle in Urban Crashes
, M.Sc. Thesis Sharif University of Technology ; Kermanshah, Mohammad (Supervisor)
Abstract
Nearly 1.2 million people die in road crashes each year, and as many as 50 million are injured in the world. In Iran, approximately 800 thousand crashes occur annually killing up to 43 people per day. Given that over 90% of accidents are related to human factors, using models that incorporate driver’s attitudes and behavior can be highly predictive of crashes. The main objective of the current research is to examine the impact of drivers’ attitudes on road crashes along with other factors such as socio-demographic characteristics and vehicle type. This study uses data from a self-completed questionnaire among a representative sample of Iranian drivers living in Tehran. The Questionnaire...
Kinetic Study of Heterogeneous and Homogeneous Catalytic Reactions in Molecular and Ionic Solvents and Their Mixtures
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Habibi Yangjeh, Aziz (Supervisor)
Abstract
Solvatochromic parameters (ETN: normalized polarity parameter, π*: dipolarity/polarizability, β: hydrogen-bond acceptor basicity, α: hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (2-hydroxyethylammonium formate) at 25 ◦C. The applicability of nearly ideal combined binary solvent/Redlich-Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. Solute-solvent and solvent-solvent interactions were applied to interpret the results. Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/Al2O3, was carried out in...
Solvatochromic parameters for binary mixtures of an ionic liquid with various protic molecular solvents
, Article Monatshefte fur Chemie ; Volume 140, Issue 3 , 2009 , Pages 329-334 ; 00269247 (ISSN) ; Habibi Yangjeh, A ; Gholami, M. R ; Sharif University of Technology
2009
Abstract
Solvatochromic parameters (E T N , normalized polarity parameter; π, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (IL; 2-hydroxyethylammonium formate) at 25 °C. In all solutions except aqueous solution, E T N values of the media increase abruptly with the ILs mole fraction and then increase gradually to the value of pure IL. A synergistic behavior is observed for the α parameter in all solutions. The behavior of π and β are nearly ideal for all solutions except for solutions of methanol with the IL. The...
Solvent effects on the reaction rate and selectivity of synchronous heterogeneous hydrogenation of cyclohexene and acetone in ionic liquid/alcohols mixtures
, Article Journal of Molecular Catalysis A: Chemical ; Volume 306, Issue 1-2 , 2009 , Pages 11-16 ; 13811169 (ISSN) ; Habibi Yangjeh, A ; Gholami, M. R ; Sharif University of Technology
2009
Abstract
Synchronous heterogeneous catalytic hydrogenation of cyclohexene and acetone, catalyzed by Pt/Al2O3, was carried out in solutions of 2-hydroxy ethylammonium formate (a room temperature ionic liquid, RTIL) with ethanol and propan-1-ol at 25 °C. Rate constants and selectivity of the reaction (relative to cyclohexene hydrogenation) increase with mole fraction of the ionic liquid (IL). The reactants tendency to the catalyst surface increases by addition of the ionic liquid and thus the reaction rate increases, especially for cyclohexene hydrogenation. Consequently the selectivity to cyclohexene hydrogenation was increased. Single-parameter correlations of log k vs. π* (dipolarity/polarizibility)...
Kinetic study of heterogeneous catalytic hydrogenation of cyclohexene to cyclohexane in ionic liquid-alcohols mixtures
, Article Applied Catalysis A: General ; Volume 341, Issue 1-2 , 2008 , Pages 58-64 ; 0926860X (ISSN) ; Habibi Yangjeh, A ; Gholami, M. R ; Sharif University of Technology
2008
Abstract
Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/Al2O3, was carried out in solutions of 2-hydroxyethylammonium formate (a room temperature ionic liquid, RTIL) mixed with methanol, ethanol and propan-2-ol at 25 °C. The rate constants of the reaction in ionic liquid alcohol mixtures were higher than alcohol alone. First-order rate constant of the reaction in the RTIL relative to propan-2-ol is approximately 28. Furthermore, the rate constant of the reaction increases with the mole fraction of the ionic liquid. Single-parameter correlations of log k vs. normalized polarity parameter (ETN), hydrogen-bond acceptor basicity (β) and hydrogen-bond donor acidity (α) do not give...
Sampling of Complex-Networks by Considering Activity-Level of Node
, M.Sc. Thesis Sharif University of Technology ; Manzuri Shalmani, Mohammad Taghi (Supervisor)
Abstract
Many studies has been focused on extracting structural and behavioral properties of complex networks in recent decade. Online Social Networks (OSNs) are one example of complex networks. Nowadays with rapid growth of OSNs such as Facebook and Twitter, the study of OSNs has become an interesting research area. Many of recent OSN studies studied friendship networks. Friendship network is a binary unweighted network, and all of its links have the same importance. But, in reality not only all friendship links are not representative of social interactions, but also the social links have a variety of intimacy, intensity, and etc. So, all links should not be considered equal. Recently researchers...
Evaluation of the photo-catalytic degradation of pyrene using fe-doped tio2 in presence of UV
, Article Desalination and Water Treatment ; Volume 169 , 2019 , Pages 232-240 ; 19443994 (ISSN) ; Borghei, S. M ; Haji Seyed Mohammad Shirazi, R ; Sharif University of Technology
Desalination Publications
2019
Abstract
The oil-based compounds are widely used in modern human life, and the accidental release or leakage of these compounds is led to water and soil pollution and creates many problems for the environment. The purpose of this study was to determine the efficiency of photo-catalytic degradation of pyrene using Fe-doped TiO2 in the presence of UV. This experimental study was carried out at laboratory scale in a 2 L pilot reactor. The nanoparticle was synthesized by the sol-gel method. Pyrene degradation was investigated under different conditions of pH, reaction time, nanoparticle concentration and pollutant concentration. For the statistical analysis, SPSS V.16 software and one-way analysis of...
Effect of Post Buckling Rupture on the Deformation Capacity of Concentrate Braces
, M.Sc. Thesis Sharif University of Technology ; Moghaddam, Hassan (Supervisor)
Abstract
In this study the behavior of steel bracings under cyclic loading, is modeled with finite element method. Analysis have shown that after local buckling in plastic mid-span position, due to the severe geometry change, the strain grows rapidly, The sharp growth of plastic strains is entitled as strain rises. Geometry change created will cause the collapse brace speeding up. In fact, the main local buckling can be used as a determinative factor in performance base design for steel braces. So the thesis has been investigated, using the parameters fracture life to quantify local buckling and fracture. Also with using the CVGM model, the fracture of the brace could be predicted. The analytical...
Designing a Loadcell for a Walker to Measure Upper Extremities’ Forces
, M.Sc. Thesis Sharif University of Technology ; Zohoor, Hassan (Supervisor)
Abstract
In this project, two bidirectional loadcell are designed and fabricated to be installed on a walker. Then upper extremities’ forces and moments have been obtained. Results can be used for rehabilitation purposes in Spinal Cord Injuries and Cerebral Palsy cases. The method used in this project is as follows: First, since the commercial multidirectional loadcells are too expensive, the loadcell (and an appropriate electronic board) are fabricated. Ultimately, a complete gait analysis by means of VICON motion analysis and using inverse dynamic method has been held to measure upper extremities’ forces and moments in the wrist, elbow and shoulder. The results for a person with Spinal Cord Injury...
An Efficient Hardware Trojan Detector Using On-chip Ring Oscillator
, M.Sc. Thesis Sharif University of Technology ; Hesabi, Shahin (Supervisor)
Abstract
Nowadays integrated circuits are extremely vulnerable to hardware trojans (HT). Hardware trojans can be injected into the ICs in design or fabricate phase, and damage system’s functionality or security. In this thesis, we first describe hardware trojan definition, classification and types of HTs, negative effects, detection ways and analysis of them. Then we propose a new solution in order to solve the negative points of previous methods
Experimental Investigation of Microjet Engine Anomaly Detection Based on ANN Data Clustering Analysis
, M.Sc. Thesis Sharif University of Technology ; Saghafi, Fariborz (Supervisor)
Abstract
In this study, the possibility of detecting known and unknown anomalies in a micro jet engine is evaluated. the proposed method is neural network and clustering analysis. The process consists of two main parts, first part is experimental abnormal behavior simulation and second part is validation of proposed detection method. In the first part a micro jet engine (Olympuse HP) were used and we created pre-designed errors in engine normal behavior to record significant changes in its performance. Recorded outputs consist of six different variables: RPM, Exhaust gas temperature, Throttle command, Fuel pump voltage, Thrust and Fuel weight. In the second part, for analyzing data, we used...
Feasibility Study of Rapid Estimation of SF Parameter of Cells Using the Monte Carlo Simulation of Carbon Therapy in Combination with Cascade Feed-forward Neural Network (CFNN) by Bayesian Regularization Learning Algorithm
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Naser (Supervisor)
Abstract
Our main goal in this project is to calculate the cell survival fraction (SF) in unhealthy tissue after carbon ion beams are emitted and hit the target tissue. At present, in the stages of carbon therapy, it usually takes a long time to make the necessary calculations for that particular person, and this makes the treatment process progress slowly, but in this project, we intend to address this problem with Eliminating the use of neural network. The main reason is the use of carbon ions to increase efficiency in the treatment of tumors and deep cancerous tissues. To do this project, we first convert the carbon ion energy to the dose absorbed at the desired point. For this phase of the...
Effects of Microstructure and Salinity Concentration on Hydraulic Conductivity of Silty Clay Soils
, M.Sc. Thesis Sharif University of Technology ; Sadeghi, Hamed (Supervisor)
Abstract
Various contaminants and their leachate, when they penetrate into the soil, cause changes in soil microstructure, this change in microstructure leads to changes in soil permeability and volume. In this study, first, the effects of soil microstructure change on the hydraulic conductivity of saturated soil were investigated using the change in initial saturation degree during compaction for compacted samples and the change in sample construction in reconstituted samples. Also, the simultaneous effect of changing the initial microstructure and salt solution on the hydraulic conductivity of saturated silty clay soils using a three-axial permeability device with the ability to measure volume...
Fabrication and Experimental Investigation of Rotary Agnetohydrodynamic Micropump
, M.Sc. Thesis Sharif University of Technology ; Behshad Shafii, Mohammad (Supervisor)
Abstract
Considering the advantages and disadvantages of reported micropumps, we aimed to introduce a novel idea to diminish the disadvantages and promote the advantages of Magnetohydrodynamic (MHD) micropumps. This novel idea operates based on a mercury slug rotation in a circular microchannel. This cyclic motion of the mercury slug which is similar to a piston, push the fluid in the microchannel and pump the flow. However, to bring this idea into the practice, it must be integrated with a specific valve. Fluid has not to go through this specific valve. In contrary, mercury slug has to pass across this valve. These two specifications must be considered during the design process of the valve. On the...
Mathematical Modeling of Slurry Reactor for Direct Synthesis of Dimethyl ether from Syngas and Carbon Dioxide
,
M.Sc. Thesis
Sharif University of Technology
;
Kazemeini, Mohammad
(Supervisor)
Abstract
In this study, both axial dispersion and perfect mix mathematical model to simulate a three-phase slurry bubble column reactor for direct synthesis of dimethyl ether (DME) from syngas and CO2 is developed. This large-scale reactor is modeled by using mass and energy balances, catalyst sedimentation and single-bubble as well as; two-bubbles’ class flow hydrodynamics. A comparison between the two hydrodynamic models with pilot plant experimental data from the literature showed that heterogeneous two-bubbles flow model is in better agreement with the experimental data than homogeneous single-bubbles gas flow model. Also, by investigating the heterogeneous gas flow and axial dispersion model for...
, M.Sc. Thesis Sharif University of Technology ; Matloubi Moghaddam, Firouz (Supervisor)
Abstract
1,3-Dipolar cycloaddition reactions constitute one of the most fundamental reactions for construction of five-membered heterocyclic compounds Spiro and dispirooxindoles have become important synthetic targets as these structural frameworks form the core units of many naturally occurring molecules that possess abundant biological activities .In this report we used (E)-Aryl ideneindolinones as unusual dipolarophiles for synthesis of dispirooxindoles. In follow different bifunctional nucleophiles for example 1,3-dicarbonyl, phenol, thioindole can be used in synthesis of benzoxazocines We have reported a new and efficient synthesis of benzoxazocines via unique tandem 1,3-dinucleophilic addition...