The ∑ 1-Provability Logic of Intuitionistic Arithmetic

, Ph.D. Dissertation Sharif University of Technology Mojtahedi, Mojtaba (Author) ; Ardeshir, Mohammad (Supervisor)

Abstract

In this dissertation, we study (first-order) arithmetical interpretations for propositional (modal and non-modal) logics. More precisely, the following results are included in this dissertation: an axiomatization for provability logic of Heyting Arithmetic, HA, and its self-completion HA := HA + PrHA(⌜A⌝) ! A for 1-substitutions is provided, and their arithmetical completeness theorems are proved. We also show that they are decidable. The de Jongh property for Basic Arithmetic BA, HA and HA + □ are proved

Optimization of Pressure Leaching of Chalcopyrite Concentrate with Oxygen and Kinetics Study of the Process in Sulfuric Acid Solution

, M.Sc. Thesis Sharif University of Technology Mojtahedi, Behrad (Author) ; Yoozbashizadeh, Hossein (Supervisor)

Abstract

The enormous benefits of hydrometallurgical processes have led to the progressive metals extraction industry. Many studies are carried out on the application of these processes in the copper extraction industry. In this research, the oxygen pressure leaching of chalcopyrite concentrate was studied. Experiments were carried out under conditions of the solid-liquid ratio of 0.1, agitation speed of 750 rpm, and sulfuric acid concentration of 2M in a stainless-steel autoclave system. Central composite design (CCD) was used to design experiments, and three factors of temperature, time, and pressure of oxygen, were selected as design variables. The obtained model for %Cu includes parameters of...

Assessment of Water and Sewage Facilities of Kish Island and Offering Solutions in Emergency Conditions (A Case Study on Kish Island)

, M.Sc. Thesis Sharif University of Technology Mojtahedi, Amir (Author) ; Hashemian, Jamal (Supervisor)

Abstract

Vulnerability of water and sewage infrastructure in Kish Island survey versus natural and unnatural threats. It is important to know what to do when crisis or unpredicted event occurs in the Island. Decision makers and master managers of the Island, as the main custodians make suitable and effective reactions and decisions so that the impact of threats is reduced to minimum. According to the threats, there are short term and long term solutions. These solutions can be applied when the Island is encountered with crisis

Pressure leaching of chalcopyrite concentrate with oxygen and kinetic study on the process in sulfuric acid solution

, Article Transactions of the Indian Institute of Metals ; Volume 73, Issue 4 , 6 March , 2020 , Pages 975-987 Mojtahedi, B ; Rasouli, S ; Yoozbashizadeh, H ; Sharif University of Technology

Springer 2020

Abstract

In this research work, the pressure leaching of chalcopyrite concentrate with oxygen was studied. Experiments were carried out under conditions of the solid–liquid ratio of 0.1, agitation speed of 750 rpm, and sulfuric acid concentration of 2 M in a stainless-steel autoclave system under 0.6 to 1 MPa oxygen gas. Central composite design was used to design experiments, and three factors of temperature, time, and oxygen pressure were selected as the design variables. A linear model for %Cu and a quadratic model for %Fe were proposed by Minitab Software. The results showed that temperature is the most effective factor in chalcopyrite leaching. Under optimal conditions, 93.08% of copper with the...

Investigation of Ardabil Plain Subsidence with Respect to Changes in Groundwater Level and Climate Fluctuations

, M.Sc. Thesis Sharif University of Technology Fazel Mojtahedi, Farid (Author) ; Khosravi, Ali (Supervisor)

Abstract

The subsidence phenomenon in the past years has caused many problems and issues for the agricultural lands, roads, power transmission lines, energy etc., due to different reasons including over use of groundwater resources and changes in climate. This phenomenon has been observed in different plains of the country including the Khorasan, Kerman, Hamedan, Ghazvin and Isfahan plains and has caused many damages to infrastructure and agricultural products in the mentioned regions. In this research the main factors which have affected the subsidence phenomenon especially reduced ground water table and climate changes in Ardebil plain, are taken into account and some studies which comprise...

An Artificial Intelligence Based Data-Driven Method for Forecasting Unconfined Compressive Strength of Cement Stabilized Soil by Deep Mixing Technique

, Article Geotechnical and Geological Engineering ; Volume 41, Issue 1 , 2023 , Pages 491-514 ; 09603182 (ISSN) F. Mojtahedi, F ; Ahmadihosseini, A ; Sadeghi, H ; Sharif University of Technology

Springer Science and Business Media Deutschland GmbH 2023

Abstract

The cost constraints imposed on construction projects specially ground improvements by the deep mixing technique (DMT) highlight the role of efficient optimization. In this study, a systematic artificial neural network (ANN)-based method to address this practical issue is presented. To achieve this goal, the mutual information method is firstly used to select the most important input parameters for training. Secondly, different ANN architectures are examined to find the network with the smallest error by training and optimizing several multi-layer perceptron networks using a grid search-based technique. The model is then generalized by employing the K-fold and Hold-out cross-validation...

Unification types in Euclidean modal logics

, Article Logic Journal of the IGPL ; Volume 31, Issue 3 , 2023 , Pages 422-440 ; 13670751 (ISSN) Alizadeh, M ; Ardeshir, M ; Balbiani, P ; Mojtahedi, M ; Sharif University of Technology

Oxford University Press 2023

Abstract

Efficient and practical solvent-free oxidation of alcohols using microwave irradiation

, Article Journal of Chemical Research - Part S ; Issue 6 , 2002 , Pages 286-287 ; 03082342 (ISSN) Mojtahedi, M. M ; Sharifi, A ; Kaamyabi, S ; Saidi, M. R ; Sharif University of Technology

Scientific Reviews Ltd 2002

Abstract

Alcohols are oxidised rapidly to the corresponding carbonyl compounds by montmorillonite KSF or silica supported barium manganate, under solvent-free conditions and microwave irradiation

Microwave-assisted aminomethylation of electron-rich compounds under solvent-free condition

, Article Synthetic Communications ; Volume 30, Issue 1 , 2000 , Pages 69-72 ; 00397911 (ISSN) Mojtahedi, M. M ; Sharifi, A ; Mohsenzadeh, F ; Saidi, M. R ; Sharif University of Technology

Marcel Dekker Inc 2000

Abstract

Electron-rich aromatic compounds react with formaldehyde and a secondary amine under solvent-free condition, in the presence of acidic alumina in a commercial microwave oven or at room temperature to produce aminomethylated products in good to excellent yields

Preparation, Surface Modification and Application of Nanocomposite Membranes Based on Transition Metals- Dichalcogenide Nanoparticles in Forward Osmosis Desalination Process

, Ph.D. Dissertation Sharif University of Technology Nikkhoo, Mohammad (Author) ; Bagherzadeh, Mojtaba (Supervisor) ; Ahadian, Mohammad Mahdi (Supervisor) ; Amini, Mojtaba (Supervisor)

Abstract

Different parts of this research are focused on developing FO membranes and improving their performance. For this purpose, thin film composite (TFC) membranes with fixed composition of polyethersulfone/polyamide (PES/PA) have been used to investigate the effect of nanocomposites containing transition metal dichalcogenides (TMDs) on their performance. The support layer in all cases is PES, which is prepared through the phase inversion process and does not contain any nanofillers. The modification process takes place in the polyamide layer by dispersing the desired nanoparticles in the aqueous monomer solution necessary to form this active layer. Identification and characterization of...

Synthesis, Structure and Catalytic Application of Mn, Fe and Mo Complexes with Schiff base and Oxazoline ligands and Theoretical Mechanistic Studies on the Role of Heme and non-Heme Iron(IV)-Oxo Species in Hydroxylation and Epoxidation Reactions

, Ph.D. Dissertation Sharif University of Technology Tahsini , Laleh (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

The first part of this thesis describes the synthesis and characterization of several Mn, Fe and Mo complexes containing tridentate Schiff base and oxazoline ligands and their reactivities as catalysts in the oxidation of organic compounds like olefins and sulfides, as well. The crystal structures of newly prepared cis-dioxo-bis[2-(2′-hydroxyphenyl)-oxazolinato]molybdenum(VI), cis-[MoO2(phox)2] and (N-hydroxyphenyl-salicylidenamine)(acetylacetonato)ethanol iron(III), [FeIII(N-OPh-sal)(acac)EtOH] complexes have been described by X-ray crystallography. Due to the difficulties in the preparation of suitable single crystals of novel...

Design and Fabrication of RFID Front END Transceiver single chip with 2.5W Output Power

, Ph.D. Dissertation Sharif University of Technology Javidan, Javad (Author) ; Atarodi, Mojtaba (Supervisor)

Abstract

This thesis deals with the front-End of an Integrated RFID Reader operated in 860MHz to 960MHz, which integrates a RF transceiver including PA, LNA and Mixer. In the receiver part, a power amplifier was fabricated and measured and in the transmitter part, LNA and Mixer were designed. There is a growing interest in utilizing CMOS technologies for RF power amplifiers (PAs). Although several advances have been made recently to enable full integration of PAs in CMOS, it is still among the most difficult challenges in achieving a truly single-chip radio system in CMOS. This is exacerbated by supply voltage reduction due to CMOS technology scaling and on-chip passive losses due to the conductive...

, M.Sc. Thesis Sharif University of Technology Hatami, Mojgan (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

Inert gold become catalytically active when dispersed in the form of nanoparticles. Isolated gold nanoparticles have demonstrated high catalytic activity for both oxidation and reduction reactions. In order to obtain high catalytic activity, gold nanoparticles are generally dispersed on support materials, among which oxides are commonly used. However, a substantial decrease in activity and selectivity of the immobilized catalysts is frequently observed due to the heterogeneous nature of these support materials in reaction media. In the course of our study on the metal-based catalysis for synthesis of organic compounds, we herein report that rod-shaped Au nanoparticles in aqua solution...

Synthesis and Characterization of a novel Ruthenium(II) Complex With Bidentate O,N-donor OxazolineLigand and Study of Catalytic Oxidation of Sulfides and Alkanes

, M.Sc. Thesis Sharif University of Technology Hosseini, Mojtaba (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

The 2-(2′-hydroxyphenyl)-oxazoline ligand (Hphox) is generated from 1:1 condensation of methyl salicylate with 2-aminoethanol. Novel [Ru(Hphox)2(H2O)2] (Hphox = 2-(2′-hydroxyphenyl)-oxazoline ) complex has been synthesized and characterized by physic-chemical methods. Oxidation of sulfides catalyzed by the mixed-ligand ruthenium(II) complex [Ru(Hphox)2(H2O)2]using urea-hydrogen peroxide (UHP) as oxidant was investigated under mild condition within 1 h. The results showed that mixed-ligand ruthenium(II) complex was effective catalyst in oxidation of sulfides in whichsulfoxideswere the only products. Using this catalytic system in the oxidation of alkanes, ketones were obtained as the main...

Synthesis of Core-Shell Nanoparticles Supported Iron and Vanadium Schiff Base and Their Application as a Catalyst for Oxidation of Sulfides, Alcohols and Olefins

, M.Sc. Thesis Sharif University of Technology Payab, Ebrahim (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

In this work, synthesized Fe3O4 magnetic nanoparticles andcoated with SiO2 to prepare magnetic core-shell nanoparticles. Then immobilized Schiff baseof iron and vanadium complexes on magnetic core-shell nanoparticles was prepared as a recoverable magnetic nano catalysts. These catalysts were named Fe3O4@SiO2@L1@Fe, Fe3O4@SiO2@L2@Fe and Fe3O4@SiO2@L3@V. Furthermore,olefines epoxidation, sulfides and alcohols oxidation were studied with using iron and vanadium magnetic nano catalysts. The supported catalysts were characterized by atomic absorption, FT-IR and UV–Vis spectra.The catalytic performance of the synthesized iron catalyst was tested for the epoxidation of cyclohexene, styrene and...

Preparation of Heterogeneous Catalysts by Immobilization of Molybdenum and Manganese-shiff Base Complexes into the Nanopores of Zeolite and SBA-15

, Ph.D. Dissertation Sharif University of Technology Zare, Maryam (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

This thesisconsiders new fundamental approaches to yield heterogeneous catalysts in to three sections. The first section described the immobilization of the molybdenum-Schiff base complexes in pores of SBA-15 in two different methodologies depending on the actual structure of the complexes., (i) stepwise formation of the complex by initial covalent anchoring of one of the components and consecutive solid phase synthesis consisting of the condensation of the other components of the salen complex (iii) one-step complex immobilization by covalent binding through the ligand.Based on the first methodology, we report the preparation of ordered mesoporous silica SBA-15 containing a molybdenum...

Synthesis and Characterization of Various Transition Metal Complexes and the Application in Oxidation, Heck, Suzuki, Sonogashira and Olefin Metathesis

, Ph.D. Dissertation Sharif University of Technology Amini, Mojtaba (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

In nature, catalysis is of vital importance in a wide variety of biochemical processes catalyzed by metalloenzymes. The functions performed by the metalloenzymes and their significance have inspired a range of biomimetic studies, and intense efforts have been concentrated on the synthesis of low molecular weight complexes to model the spectroscopic features of such enzymes. Concomitantly, a challenging frontier in the field of biomimetic chemistry is the development of highly reactive model compounds that are able to effect rapid and selective substrate conversion. Some important catalytic transformations that have gained attention in recent years involve the carbon-carbon coupling, olefin...

Synthesis and Study of Catalytic Reactivity Oxo Vanadium (IV)& (V) Complexes with N,N'-Ethylenebis(Salicylimine)Ligand in Oxidation of Sulfides and Epioxidation of Olfins by Urea Hydrogen Peroxide (UHP) and Tert-Butyl Hydroperoxide (TBHP)

, M.Sc. Thesis Sharif University of Technology Nadiri, Siheila (Author) ; Bagherzadeh, Mojtaba (Supervisor)

Abstract

The selective oxidation of sulfides to sulfoxides is an important method in organic synthesis because sulfoxides are useful synthetic intermediates for the construction of various chemically and biologically significant molecules. To date, the most important method of preparation involves the oxidation of sulfides. Various oxidizing agents are used for this purpose. Oxovanadium(IV)(Salen) and oxovanadium(V)(Salen)Cl were synthesised and screened in the vanadium-catalysed oxidation of sulfides to solfuxides with urea hydrogen peroxide(UHP) as terminal oxidant. Both complexes showed good activity and selectivity trough the catalytic reaction.characterized by elemental analyses, IR, 1H and 13C...

Design and Implementation of Fully Integrated Frequency Synthesizer for Biomedical Applications

, M.Sc. Thesis Sharif University of Technology Aghlmand, Fatemeh (Author) ; Atarodi, Mojtaba (Supervisor)

Abstract

Fully integrated frequency synthesizer is one of the important system-on-chips building blocks. Among this circuit’s remarkable applications, Bioelectronics field is very common. In these applications, advanced microelectronic circuits are used in order to diagnosis and treatment of diseases. The aim of this thesis is design and implementation a wideband frequency synthesizer in a 0.18um CMOS technology. The main usage of this circuit is in a fully integrated implantable biomedical sensory chip. This circuit generates two necessary local signals in sensory chip to stimulus cells and process the information.
Frequency synthesizer is based on phased locked loop (PLL) circuit and produce...

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 Mahmoudi, Hamed (Author) ; 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...