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    Selective synthesis of conjugated enynes from α-arylalkynols using LiCl-Acidic Al2O3 under solvent-free conditions [electronic resource]

    , Article Journal of Chemical Research ; Volume 2002, Number 8, 1 August 2002, pp. 378-380(3) Pourjavadi, A. (Ali) ; Bagheri Marandi, Gholam
    Abstract
    Free Content Selective synthesis of conjugated enynes from α-arylalkynols using LiCl-Acidic Al2O3 under solvent-free conditions  

    Selective preparation of fluorescent 1,8-naphthalimides using acidic alumina under microwave irradiation [electronic resource]

    , Article Journal of Chemical Research ; 01/2001; 2001(11):485-487 Pourjavadi, A. (Ali) ; Bagheri Marandi, Gholam
    Abstract
    7H-benzimidazo[2,1-a]benz[de]isoquinolin-7-one compounds were prepared in a selective manner by reaction between o-phenylenediamines and appropriate 1,8-naphthalenedicarboxylic anhydrides using acidic alumina under microwave irradiation  

    Modification of carbohydrate polymers via grafting in air. 1. Ceric-Induced synthesis of starch-g-polyacrylonitrile in presence and absence of oxygen [electronic resource]

    , Article Starch - Starke ; Volume 54, Issue 3-4, pages 140–147, April 2002 Pourjavadi, A. (Ali) ; Zohurian Mehr, Mohammad J
    Abstract
    Monomer grafting, a unique technique for polysaccharide modification, is always performed under inert (e.g., N2) atmosphere. This work is the first report related to evaluating the possibility and efficiency of the grafting of acrylonitrile (AN) onto starch in presence of oxygen. Thus, corn starch (in both granular and gelatinized states) as well as soluble starch were grafted by AN using a ceric-carbohydrate redox initiating system. Graft copolymerizations were performed under nitrogen, air, and oxygen atmospheres at similar conditions. Grafting occurrence was verified using chemical and spectral proofs. The polymerization mechanism and kinetics were investigated by recording the... 

    Mesoporous silica nanoparticles (MCM-41) coated PEGylated chitosan as a pH-Responsive nanocarrier for triggered release of erythromycin [electronic resource]

    , Article International Journal of Polymeric Materials and Polymeric Biomaterials ; 2014, Volume 63, Issue 13, Pages 692-697 Pourjavadi, A. (Ali) ; Mazaheri Tehrani, Zahra ; Sharif University of Technology
    Abstract
    A pH-responsive drug delivery system based on core shell structure of mesoporous silica nanoparticle (MSN) and chitosan-PEG copolymer was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and high-resolution transmission microscope (HR-TEM) techniques. In order to improve compatibility MSN and drug, mesoporous nanosilica was modified by 3-aminopropyl triethoxysilane. The release of erythromycin (a macrolide antibiotic) as a model drug was investigated in two pHs, 7.4 and 5.5  

    Silica chloride/wet SiO2 as a novel heterogeneous system for the deprotection of acetals under mild conditions [electronic resource]

    , Article Phosphorus, Sulfur, and Silicon and the Related Elements ; Volume 178:2667-2670, Issue 12, 2003 Mirjalili, B. F. (BiBi Fatemeh) ; Pourjavadi, Ali ; Zolfigol, Mohammad Ali ; Bamoniri, Abdolhamid
    Abstract
    A combination of silica chloride and wet SiO2 was used as an effective deacetalizating agent for the conversion of acetals to their corresponding carbonyl derivatives under mild and heterogeneous condition  

    Synthesis and Investigation of the Swelling Behavior of Superabsorbents Based on Gelatin and k-Carrageenan and Loading of KNO3 as aModel of Agrochemical Onto Them

    , M.Sc. Thesis Sharif University of Technology Ghashghaie, Ulduz (Author) ; Pourjavadi , Ali (Supervisor)
    Abstract
    This thesis focuses on the preparation and super-swelling behavior of a superabsorbent hydrogel based on natural macro-molecules and loading potassium nitrite as an agro-chemical onto it. 1-In this investigation a new type of superabsorbent hydrogel based on Gelatin and k-Carrageenan was prepared and the effect of the feed ratio of some components (acrylic acid, MBA, APS, and agar) on the swelling capacity of the hydrogel was systematically studied. The structure of the hydrogel optimized final product was found to be 1064 g/g in distilled water. The structure of the hydrogel was characterized by FT_IR method and morphology of the samples was examined by scamming electron microscopy (SEM).... 

    Synthesis of Novel Biodegradable Collagen-Based Superabsorbent Hydrogels and Investigation of their Swelling Behavior in Various Media

    , Ph.D. Dissertation Sharif University of Technology Salimi,Hamid (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    The use of super-swelling polymers is steadily increasing and the applications in industry are continuing to grow. With the authorization of the superabsorbents in food packaging by the Food and Drug Administration recently, demand may soon take off in the market. The worldwide production of SAPs is more than one million tons per year, representing a multibillion-dollar market. However, the increase in prices of petroleum products in recent years may be a drawback for these acrylic-based materials. Thus, there is now a need to develop natural-based super-swelling hydrogels which are more economical and environment friendly. In addition, the super-swelling gels are promising novel functions... 

    Hydrolyzed Protein-Based Highly Porous Hydrogels: Synthesis and Characteristics

    , Ph.D. Dissertation Sharif University of Technology Kurdtabar, Mehran (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    This thesis focuses on the preparation and super-swelling behavior of four highly porous hydrogels: 1. Firstly, we have developed a collagen-based highly porous hydrogel by neutralizing the grafted poly(acrylamide-co-acrylic acid) after gel formation. Systematically, the certain variables of the graft copolymerization were optimized to achieve maximum swelling capacity. Morphology of the samples was examined by scanning electron microscopy (SEM) and was shown the pores were induced into the hydrogel by water evaporation resulting from neutralization process. The absorbency under load (AUL) and centrifuge retention capacity (CRC) were measured. The synthesized hydrogel exhibited a... 

    Synthesis of γ-Fe2O3 Nanoparticles by Gelatin Mediator and Synthesis of γ-Fe2O3/SiO2/PCA/Ag-NPs Nanostructure Drug Delivery System

    , M.Sc. Thesis Sharif University of Technology Masoud, Nazila (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Maghemite (γ-Fe2O3) nanoparticles were produced after high temperature oxidation of gelatin-Fe3O4 nanocomposite, obtained from a common coprecipitation process of Fe2+ and Fe3+ ions in an alkaline medium in the presence of a gelatin protein as an effective mediator. Size, shape, surface morphology and magnetic properties of the prepared γ-Fe2O3 nanoparticles were characterized using XRD, FTIR, TEM, SEM and VSM data. The results revealed that primary, gelatin-Fe3O4 nanocomposite had been formed and next, the gelatin decomposition in furnace produced a spinel structure of γ-Fe2O3. The effects of furnace temperature and time of heating together with the amount of gelatin on the produced... 

    Synthesis of Green Catalyst Based on Starch and its Application in Knovenagel Reaction

    , M.Sc. Thesis Sharif University of Technology Nikooseresht, Navid (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Polysaccharide is important in terms of their environmental interest, scientists have been growing. According to the structural properties of this interesting class of natural polymers, in terms of having chemically active groups on the high density polymer housing provides the possibility That can perform chemical reactions with the new properties of these polymers to give. Starch polysaccharides in the project through a chemical reaction to the structure of a third type of bridge Amen to that using 1HNMR and 13CNMR predicted structure was approved. The modified polysaccharide has catalyst activity. This activity in knovenagel reaction for some aldhydes was used and results were... 

    Investigation of Plasticizing and Slump Retaining Properties of
    PEG-Based Tri-Block Copolymers in Cementitious Systems

    , M.Sc. Thesis Sharif University of Technology Doroudian, Mohadese (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Plasticizers in cementitious systems are additives that upon addition at a low dosage can change the workability, mechanical strength and other properties of cement paste effectively. In this study, tri-block copolymers based on poly ethylene glycol (PEG) was synthesised and their applications in the cementitious systems investigated. The main purpose is the verification of plasticizing effects of these copolymers in the cement paste. ABA tri-block copolymers with PEG (1000 and 1500 g/mol) as B block, poly caprolactone, poly caprolactam, poly lactide and poly glycolide (with different weight ratio) as A block were synthesised via ring opening polymerization with stannous octanoate as... 

    Preparation and Evaluation of Nanopolysaccharides- & Polysaccharides-Anticancer Drugs Conjugates

    , Ph.D. Dissertation Sharif University of Technology Akhlaghi, Mehdi (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In recent years, cancer is the second leading cause of human death. Cancer treatment is based on surgery, chemotherapy and radiation therapy. Choice of treatment method depends on the degree of progression and type of cancer. However, the goal is destruction of cancer cells and minimal harmful side effects on healthy cells. In this thesis two types of polysaccharide-anticancer drug conjugate were prepared and evaluated for radiation therapy and chemotherapy; chitosan- and DTPA modified chitosan – Gallium 66 conjugates for radiation therapy and nano diacid starch –cisplatin conjugate for chemotherapy. Chitosan –gallium 66 conjugate was prepared in radiochemical purity higher than 99% at... 

    Synthesis and Application of Superabsorbent Nanocomposites for Optimized Performance in Cement-based Materials

    , Ph.D. Dissertation Sharif University of Technology Fakourpour, Mahmoud (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Superabsorbent polymers are mainly used in baby diapers and in agriculture. A less known emerging and potentially important application is the internal curing of cement based materials. About a decade ago, pioneering works demonstrated that using SAP in concrete reduces autogenous shrinkage and cracking, and improves hydration of the cement matrix. However, problems like workability reduction, and deterioration of mechanical strength of the mixture are reported. In this thesis, nanocomposites using nanosilica and acrylic monomers were prepared and used to address the above problems. Nanocomposites exhibit enhanced mechanical strength and reduced sliding friction, compared with conventional... 

    Synthesis of Magnetic Fe3o4 Nanoparticle and Coating It with Modified Starch for Targeted Delivery of Doxorubicin Anticancer Drug

    , M.Sc. Thesis Sharif University of Technology Alizadeh, Mahshid (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    One of the major problems in cancer treatment is side effects of treatments. Today, scientists have developed smart nanocarrier for diagnosis and drug delivery that can circulate in the bloodstream, pass the body's immune system to kill cancer cells and attach to the cancer cells to deliver drugs, without the side effects that are in other treatments, such as chemotherapy. magnetic nanoparticles coated by biodegradable polymers are one of the smart polymers. In this study, iron oxide nanoparticles with amine group on their surface are coated by starch modified by methyl acrylate then reacted with hydrazine and hydrazide functional group is formed that can chemically be bonded with the... 

    Synthesis of Pyrene-Based Supramolecular Nanomaterials and Investigation of its Cellular Toxicity of Antitumor and Activities

    , M.Sc. Thesis Sharif University of Technology Eskandari, Mohammad (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In this work, pH sensitive supramolecular shuttles consisting of carbon nanotube-graft-pyrene (CNT-graft-PYR) and hyperbranched polyglycerol with β-cyclodextrin core (β-CD-graft-PG) were synthesized and characterized. Supramolecular systems (PG/CNT/S) were able to load and transport doxorubicin in aqueous solutions. While PG/CNT/S were soluble in phosphate buffer pH 7, they were divided to their individual moieties in pH 5 and therefore CNTs containing staked doxorubicin molecules were precipitated  

    The Effect of Protein Corona on Doxorubicin Release from the Magnetic Mesoporous Silica Nanoparticles and the Effect of Polyethylene Glycol Coating on drug Delivery System

    , M.Sc. Thesis Sharif University of Technology Mahmoudi, Negar (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    The nanoparticles have been widely used in the field of physics, chemistry, electronics and mechanics because of their high surface area. One of their most important applications is in drug delivery systems as smart drug nanocarrier. Magnetic nanoparticles (including Fe2O3, Fe3O4) are the good candidates for this purpose. It is clear that, upon to entrance of nanoparticle into biological media (such as plasma), the surface of nanoparticles were covered by protein layers (protein corona). This layer is very stable and created new surface on the nanoparticles. The protein corona layer intracts with cellular receptors and determines the fate of nanoparticles. Protein corona covers the targeting... 

    Synthesis of Organic Solvent Absorbent Crosslinked Polymers Based on Carbon Nanotubes and Hydrophobic Monomer

    , Ph.D. Dissertation Sharif University of Technology Doulabi, Malihe (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In this thesis, organic solvent absorbent crosslinked polymers based on carbon nanotubes and hydrophobic monomers were synthesized by radical polymerization. Surfaces of carbon nanotubes were modified for the better dispersion in a polymeric matrix and participation in polymeric reactions. Different hydrophobic monomers such as diphenyl acrylamide and ionic liquids based on vinyl imidazolium cation with long alkyl chain and lipophilic counter anion such as tetrafluoro borate were synthesized and utilized with hydrophobic long alkyl chain acrylate monomers for the preparation of organogels. Swelling behavior of synthesized organogels in different organic solvents was investigated. The results... 

    Preparation of Magnetic Gels based on Modified Magnetite Nanoparticles for Organic Solvents Absorption

    , M.Sc. Thesis Sharif University of Technology Nourani, Mohammad (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In recent years, parallel to the development of industrial, the use of organic solvents and the environmental pollution caused by their increasing, more attention to remove these contaminants growing. Among the various absorbents to absorb pollutants from the environment, iron oxide nanoparticles have many applications in absorption and removal of environmental pollutions due to their high specific surface area, magnetic properties and ease of separation. The aim of this research is synthesis of a magnetic gel for absorption of organic solvents which in its structure magnetic nanoparticle and hydrophobic monomer is used. The most important advantages are the ease of isolation of the desired... 

    Preparation of Graphene Oxide Magnetic Nanoparticles with Mesoporous Silica Layer, Coating with pH-Sensitive Polymer as Nanocarriers of Anticancer Drugs

    , M.Sc. Thesis Sharif University of Technology Shakerpoor, Alireza (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    Man’s struggle for optimization in different areas has been an endless one. Optimizing methods of cancer treatment is not an exception. Because of numerous side effects of anti-cancer drugs, drug delivery systems (DDS) have been recently given much interest. Considering some aspects, DDS are helpful in reducing harmful effects of anti-cancer drugs and more efficient healing by these drugs: first by reducing the dosage of drug by controllable and sustainable release of drug in a kinetic (diffusion) pattern; second by smart release of drug in target tissue which in turn protects sound tissues not to be in contact with drug.In this study, three kinds of nanoparticles have been used for DDS... 

    Synthesis and Application of Magnetic Nanocatalysts Cated by Ploy (Ionic Lquid) s

    , Ph.D. Dissertation Sharif University of Technology Hosseini, Hassan (Author) ; Pourjavadi, Ali (Supervisor)
    Abstract
    In this thesis, heterogenous catalysts based on poly(ionic liquids) were synthesized. These catalysts were prepared by polymerization of functionalized ionic liquid monomers in the presence of an ionic cross-linker. Several types of poly(ionic liquids) such as acidic ionic liquid, basic ionic liquid and their complexs with copper and palladium were prepared. Some of these polymers were coated onto the magnetic nanoparticles to produce a catalyst with magnetic prppertise with easy magnetic separation from the reaction medium. Such catalysts have high loading level and high thermal stability. Most of prepared catalysts have high loading level due to the macromolecular nature of polymer. At the...