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Synthesis of Five Membered Nitrogen Containing Heterocycles Including Pyrrole, Imidazole and Tetrazole in Aqueous Media
, Ph.D. Dissertation Sharif University of Technology ; Mahmoudi Hashemi , Mohammad (Supervisor)
Abstract
This thesis contains four chapters. In first chapter the role of water in organic reactions as a ecofriendly solvent, computational chemistry and dynamic nuclear magnetic resonance were studied. In the second chapter synthesis of new 4-hydroxy pyrrole derivatives in water were reported. For the synthesis of these compounds arylglyoxal derivatives, 1,3-dicarbonyl compounds and ammonium acetate were used. The reaction conditions are very mild. The third chapter contains the synthesis of new (4 or 5)-Aryl-2-aryloeil-(1H)-imidazole compounds in aqueous media. We also investigated the tauto-isomerisation of isomeric imidazoles during this reaction using DNMR technique. In forth chapter a...
Aza Michael Addition of Amines to α,β-Unsaturated Compounds and Alkene Epoxidation
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor)
Abstract
This thesis contains two parts .In the first part a catalyst such as AlCl3/Al20 has been demonstrated to catalyze Michael addition reaction of amines to a,�- unsaturated compounds with high yields , short reaction time and under solvent-free condition.The Michael addition to a,�- unsaturated compounds produces quantitively the mono addition products.The next part is about olefins epoxidation . Alkene epoxidation is a useful reaction in organic synthesis. Epoxides play an important role in industrial intermediates for the production of fine chemicals as well as pharmaceuticals .The hydrogen peroxide has been used as an oxidant because it is considered as an economical and appropriate reagent...
Synthesis of β-Amino Ketones Using Titania Based on Solid Acid as A Catalyst
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor)
Abstract
Enanthioselective synthesis of biological molecules are so important in synthetic chemistry, and because of their biological activities, β-amino carbonyl compounds have earned so much attention in this area of chemistry. Mannich reaction is a classical method for synthesis of these molecules. The Mannich reaction is a three-component reaction between an enolizable CH-acidic carbonyl compound, an amine, and an aldehyde producing β-amino carbonyl compounds. But acidic or basic difficult circumstances, long reaction time, low yield and enantioselectivity, are the drawbacks of classical methods. In this project, we used titania-based solid acid as an enantioselective catalyst to overcome these...
Microwave-expedited synthesis of aromatic aldehydes and ketones from alkyl halides without solvent using wet montmorillonite K 10 supported iodic acid as oxidant
, Article Acta Chimica Slovenica ; Volume 51, Issue 2 , 2004 , Pages 333-336 ; 13180207 (ISSN) ; Rahimi, A ; Ahmadibeni, Y ; Sharif University of Technology
2004
Abstract
The efficient microwave-assisted synthesis of aldehydes and ketones over wet montmorillonite K 10 using HIO3 as oxidizing agent is described. This fast oxidation protocol is applicable to variety of alkyl halides
The Neuroscience of Religious Experience: On John Hick Work about Religion and Neuroscience
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Hassan (Supervisor)
Abstract
The study of the religious experience is always one of the most important topics in researches related to the religion field. Religious and mystical experiences have always been one of the key religious concepts. The religious experience, like other human experiences, always comes with reactions in the human brain. Study of the religious experience from a neuroscience perspective can help us to answer questions and issues in the field of religious experience and cognitive credit of it. Assessment of what happens in the people’s brain during rituals like meditation or deep concentration provides a good window into understanding of what this means for people, being mystical or religious or...
Selective aqueous oxidation of alcohols catalyzed by copper (II) phthalocyanine nanoparticles
, Article Comptes Rendus Chimie ; Volume 19, Issue 3 , 2016 , Pages 313-318 ; 16310748 (ISSN) ; Kheirjou, R ; Rezayan, A. H ; Shakourian Fard, M ; Mahmoudi Hashemi, M ; Sharif University of Technology
Elsevier Masson SAS
2016
Abstract
A new catalyst based on metallophthalocyanine nanoparticles has been synthesized and characterized by scanning electron microscopy (SEM). The aqueous oxidation of alcohols to the corresponding carbonyl compounds (aldehydes and ketones) has been studied using tetra-n-butyl-ammonium-peroxo-monosulfate (n-Bu4NHSO5) as an oxidant and a catalytic system consisting of copper (II) phthalocyanine nanoparticles in water. The highly selective oxidation gave excellent yields of related aldehydes or ketones without remarkable over-oxidation of the carboxylic acids. Organic co-solvents, surfactants, and co-catalysts were not used in this catalytic strategy. This strategy was green and time effective. The...
Performance Enhancement of Piezoelectric Materials for Degradation of Organic Pollutants
, M.Sc. Thesis Sharif University of Technology ; Rahman Setayesh, Shahrbanoo (Supervisor)
Abstract
In this research, piezocatalysts ceramics Bi4Ti3-xMnxO12 (x=0,0.1,0.2,0.3) were synthesized by hydrothermal method and utilized in the process of rhodamine B piezocatalytic degradation.These piezocatalysts were characterized using XRD, FE-SEM, FT-IR, DRS and PL methods. The results of XRD patterns confirmed the formation of orthorhombic crystal structure of Bi4Ti2.9Mn0.1O12 and Bi4Ti3O12 piezocatalysts. FT-IR spectroscopy confirmed the existence of chemical bonds of piezocatalysts. FE-SEM images showed the formation of Bi4Ti2.9Mn0.1O12 and Bi4Ti3O12 nanoplates. Using DRS analysis data, the absorption edge wavelength and energy gap of the synthesized piezocatalysts were obtained. Also, the...
Studies of Ponceau 4R food colorant and zinc oxide nanoparticles containing it interactions with DNA and evaluation of their antimicrobial activity
, Article Journal of Food Processing and Preservation ; Volume 46, Issue 2 , 2022 ; 01458892 (ISSN) ; Shahabadi, N ; Mahmoudi Hashemi, M ; Meibodi, F. S ; Mirjafari, Z ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
The current study describes design and synthesis of silica-coated zinc oxide nanoparticles containing Ponceau 4R food colorant (named as ZnO@SiO2@APTMS/P4R). The interactions of Ponceau 4R and ZnO@SiO2@APTMS/P4R with calf thymus-DNA were investigated It should be noted that the competitive binding experiment revealed that both Ponceau 4R and ZnO@SiO2@APTMS/P4R could release Hoechst 33258. As inferred from the results the binding of the Ponceau 4R and ZnO@SiO2@APTMS/P4R with DNA were surface binding, mainly due to groove binding. Furthermore, antibacterial properties of ZnO, Ponceau 4R and ZnO@SiO2@APTMS/P4R samples against gram-positive bacteria and gram-negative bacteria were examined and...
Surface Modification of Nanosilica with Glycidoxypropyltrimethoxysilane and Investigating its Effect on the Physical and Mechanical Properties of Epoxy Resin
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor) ; Bastani, Saeed (Supervisor)
Abstract
In the first stage of this research, different amounts of glycidoxypropyltrimethoxysilane (GPS) were grafted as a coupling agent on the surface of nanosilica particles (NS). Surface characterization was done by Particle Size Analyzer and Thermal Gravimetric Analyzer (TGA) and that way, samples were distinguished from each other. More comparisons were taken by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). Then the different amounts of modified NS were added into the matrix of an epoxy resin and the physical and mechanical properties of samples were tested with Abrasion Resistance test, Tensile Strength test, Thermal Mechanical Analysis (TMA),...
Cell shape affects nanoparticle uptake and toxicity: An overlooked factor at the nanobio interfaces
, Article Journal of Colloid and Interface Science ; Volume 531 , 2018 , Pages 245-252 ; 00219797 (ISSN) ; Ghahremani, M. H ; Hashemi, F ; Hormozi Nezhad, M. R ; Raoufi, M ; Zanganeh, S ; Atyabi, F ; Dinarvand, R ; Mahmoudi, M ; Sharif University of Technology
Academic Press Inc
2018
Abstract
Hypothesis: It is now being increasingly accepted that cells in their native tissue show different morphologies than those grown on a culture plate. Culturing cells on the conventional two-dimensional (2D) culture plates does not closely resemble the in vivo three-dimensional (3D) structure of cells which in turn seems to affect cellular function. This is one of the reasons, among many others, that nanoparticles uptake and toxicology data from 2D culture plates and in vivo environments are not correlated with one another. In this study, we offer a novel platform technology for producing more in vivo-like models of in vitro cell culture. Experiments: The normal fibroblast cells (HU02) were...
Separaition of Cu 2+ Ions from Aques Medium Using Silica Nano Pore Functionalized Amine Groups Confiend with Ionic Liquid
, M.Sc. Thesis Sharif University of Technology ; Mohammad , Mahmoudi Hashemi (Supervisor) ; Mirzaee, Mohammad (Supervisor)
Abstract
Purification of waste water containing metal ions, is one of major environmental problems which have threaten human’s life, other creatures and even agricultural products by means of polluting suberranean water. Copper ion is one of dangerous heavy metals that exists in potable water and agricultural uses, due to serious problems in health of humans and aquatic. In recent years, different methods for purification of waste water containing heavy metal ions have been published. Right now, thorough these methods such as: filtration, coagulation, precipitation and adsorption are being used, which have their own advantages and disadvantages.In this research, new method for purification of waste...
Michael Addition of Aromatic Amines and Synthesis Some Derivatives of Thiomorpholins
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimehjani, Azim (Supervisor)
Abstract
This project investigates on synthesis of β-amino carbonyl compounds with new approach to become closer to green chemistry principals.In this project, we investigated the synthesis of β-amino carbonyl compounds with aromatic amines and electron deficient alkenes in the Michael reaction using boric acid and glycerol in water as a green media. High yields of the products and easy handling are some advantages of this procedure. Also, we investigated the Michael reaction in different solvents and temperatures but gave better results in the aqueous media. Moreover, thiomorpholine derivatives were synthesized using this method to give excellent yield.
Investigation of Dithiocarabamates Reaction with α,β-Unsaturated Aldehydes
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimehjani, Azim (Supervisor)
Abstract
Dithiocarbamates are a group of compounds that nowadays have been used extensively in pharmaceutical agents, organicsynthesis and as fungicides in agriculture.We haveshown, an efficient. regiospecific method for the synthesis of cyclic dithiocarbamates by one-pot three-component cascade reaction of an amine, CS2 and α,β-unsaturated aldehyde via Michael addition/hemiamination reaction in watre under a mild and green procedure with excellent yields and complete regioselectivity
Hyperbolic involutions and quadratic extensions
, Article Communications in Algebra ; Volume 39, Issue 1 , Jan , 2011 , Pages 125-132 ; 00927872 (ISSN) ; Sharif University of Technology
2011
Abstract
This is a variation on a theme of Bayer-Fluckiger, Shapiro, and Tignol related to hyperbolic involutions. More precisely, criteria for the hyperbolicity of involutions of quadratic extensions of simple algebras and involutions of the form σ ⊗ τ and σ ⊗ ρ, where σ is an involution of a central simple algebra A, τ is the nontrivial automorphism of a quadratic extension of the center of A, and ρ is an involution of a quaternion algebra are obtained
On hyperbolic clifford algebras with involution
, Article Algebra Colloquium ; Volume 20, Issue 2 , 2013 , Pages 251-260 ; 10053867 (ISSN) ; Sharif University of Technology
2013
Abstract
The aim of this article is to provide a characterization of quadratic forms of low dimension such that the canonical involutions of their Clifford algebras are hyperbolic
Orthogonal symmetries and Clifford algebras
, Article Proceedings of the Indian Academy of Sciences: Mathematical Sciences ; Volume 120, Issue 5 , November , 2010 , Pages 535-561 ; 02534142 (ISSN) ; Sharif University of Technology
2010
Abstract
Involutions of the Clifford algebra of a quadratic space induced by orthogonal symmetries are investigated
A quick proof of the 1, 2, 4, 8 theorem
, Article Expositiones Mathematicae ; Volume 33, Issue 3 , 2015 , Pages 375-377 ; 07230869 (ISSN) ; Sharif University of Technology
Elsevier GmbH
2015
Products of rotations by a given angle in the orthogonal group
, Article Bulletin of the Australian Mathematical Society ; 2017 , Pages 1-5 ; 00049727 (ISSN) ; Sharif University of Technology
2017
Abstract
For every rotation (Formula presented.) of the Euclidean space (Formula presented.) ((Formula presented.)), we find an upper bound for the number (Formula presented.) such that (Formula presented.) is a product of (Formula presented.) rotations by an angle (Formula presented.) ((Formula presented.)). We also find an upper bound for the number (Formula presented.) such that (Formula presented.) can be written as a product of (Formula presented.) full rotations by an angle (Formula presented.). © 2017 Australian Mathematical Publishing Association Inc
A Geometric Interpretation of the Simplicity of SO(3)
, Article American Mathematical Monthly ; Volume 126, Issue 4 , 2019 , Pages 340-350 ; 00029890 (ISSN) ; Sharif University of Technology
Taylor and Francis Inc
2019
Abstract
This article aims to present a geometric interpretation of the simplicity of the rotation group of three-dimensional Euclidean space. Some historical remarks on the subject and an overview of a collection of different proofs of this result are also given
The comparison of form drag and profile drag of a wind turbine blade section in pitching oscillation
, Article World Academy of Science, Engineering and Technology ; Volume 40 , 2009 , Pages 294-301 ; 2010376X (ISSN) ; Seddighi, M ; Mahmoudi, M ; Sharif University of Technology
2009
Abstract
Extensive wind tunnel tests have been conducted to investigate the unsteady flow field over and behind a 2D model of a 660 kW wind turbine blade section in pitching motion. The surface pressure and wake dynamic pressure variation at a distance of 1.5 chord length from trailing edge were measured by pressure transducers during several oscillating cycles at 3 reduced frequencies and oscillating amplitudes. Moreover, form drag and linear momentum deficit are extracted and compared at various conditions. The results show that the wake velocity field and surface pressure of the model have similar behavior before and after the airfoil beyond the static stall angle of attack. In addition, the...