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    Application of bioaugmentation technology to improve the activated sludge treatment process in removal of aromatic compounds

    , Article 18th International Congress of Chemical and Process Engineering, CHISA 2008, Prague, 24 August 2008 through 28 August 2008 ; 2008 Yaghmaei, S ; Samie, S ; Amiri, F ; Sharif University of Technology
    The effects of bioaugmentation on maintaining the conventional activated sludge (CAS) system stability under shock loading conditions, standardizing the effluent, and improving the sludge settlement, were studied. Phenol was chosen as a model of mono-aromatic compounds, which are commonly found in the wastewaters of petroleum refineries and petrochemical industry in Iran. Bioaugmentation is a practical means to increase the resistance of a CAS system against shock loadings of recalcitrant compounds. It is also effective in removing hazardous compounds according to recommended standards. By using this method, there is no need to change CAS system construction, thus, it can be used simply and... 

    Sodium hypochlorite/montmorillonite K10: An effective oxidant for the oxidation of thiols to disulfides

    , Article Letters in Organic Chemistry ; Volume 2, Issue 5 , 2005 , Pages 485-486 ; 15701786 (ISSN) Hashemi, M. M ; Rahimi, A ; Karimi Jaberi, Z ; Sharif University of Technology
    Sodium hypochlorite adsorbed on montmorillonite K10 is a useful oxidant for the oxidation of thiols to disulfides under the room temperature. © 2005 Bentham Science Publishers Ltd  

    Solid state oxidation of phenols to quinones with sodium perborate on wet montmorillonite K10

    , Article Journal of the Brazilian Chemical Society ; Volume 16, Issue 5 , 2005 , Pages 1082-1084 ; 01035053 (ISSN) Hashemi, M. M ; Eftekhari Sis, B ; Khalili, B ; Karimi Jaberi, Z ; Sharif University of Technology
    Sociedade Brasileira de Quimica  2005
    Phenols were oxidized to quinones using sodium perborate (SPB) on wet montmorillonite as oxidant. The reaction was carried out at ambient temperature on the solid phase under solvent free conditions. ©2005 Sociedade Brasileira de Química  

    Partially hydrolyzed crosslinked alginate-graft-polymethacrylamide as a novel biopolymer-based superabsorbent hydrogel having pH-responsive Properties [electronic resource]

    , Article Macromolecular Research ; January 2005, Volume 13, Issue 1, pp 45-53 Pourjavadi, A. (Ali) ; Aminfazl, M. S ; Hosseinzadeh, H
    In this study, a series of highly swelling hydrogels based on sodium alginate (NaAlg) and polymethacrylamide (PMAM) was prepared through free radical polymerization. The graft copolymerization reaction was performed in a homogeneous medium and in the presence of ammonium persulfate (APS) as an initiator andN,N′-methylenebisacrylamide (MBA) as a crosslinker. The crosslinked graft copolymer, alginate-graft-polymethacrylamide (Alg-g-PMAM), was then partially hydrolyzed by NaOH solution to yield a hydrogel, hydrolyzed alginate-graft-polymethacrylamide (H-Alg-g-PMAM). During alkaline hydrolysis, the carboxamide groups of Alg-g-PMAM were converted into hydrophilic carboxylate anions. Either the... 

    Experimental study of hydrogen fluoride adsorption on sodium fluoride

    , Article Journal of Industrial and Engineering Chemistry ; Volume 16, Issue 1 , 2010 , Pages 147-151 ; 1226086X (ISSN) Afzal, S ; Rahimi, A ; Ehsani, M. R ; Tavakoli, H ; Sharif University of Technology
    In uranium conversion industry, the fluorine is used as chemical raw material gas to produce UF4 and UF6 while its purity is very important. In this study, the adsorption process of hydrogen fluoride, as an impurity in the process of fluorine production, on sodium fluoride pellets is experimentally studied in a lab-scale fixed bed adsorbent. Also, the effects of some operating parameters including inlet concentration and inlet temperature of hydrogen fluoride are precisely investigated on the adsorption process. The data of adsorption are analyzed and correlated by Langmuir, Freundlich and Temkin isotherms. The adsorption capacity is found to be 1.908 and 0.750 g HF/g NaF by the Langmuir... 

    One step synthesis of 14-alkyl- or aryl-14H-dibenzo[a,j]xanthenes using sodium hydrogen sulfate as catalyst

    , Article Monatshefte fur Chemie ; Volume 139, Issue 6 , 2008 , Pages 605-608 ; 00269247 (ISSN) Karimi Jaberi, Z ; Hashemi, M. M ; Sharif University of Technology
    A simple and environmentally benign procedure for the synthesis of 14-alkyl- or aryl-14H-dibenzo[a,j]xanthenes is described through a one-pot condensation of 2-naphthol with aryl or alkyl aldehydes in the presence of sodium hydrogen sulfate as a catalyst under solvent-free conditions. © 2008 Springer-Verlag  

    Simple and highly efficient catalyst- and waste-free ring opening of epoxides with Na2S in water

    , Article Monatshefte fur Chemie ; Volume 141, Issue 3 , 2010 , Pages 323-326 ; 00269247 (ISSN) Azizi, N ; Akbari, E ; Ebrahimi, F ; Saidi, M. R ; Sharif University of Technology
    Water was found to be a highly efficient and green catalyst and solvent for ring-opening reaction of epoxides with Na2S at room temperature to give substituted bis(hydroxyethyl)thioethers in high yields  

    A ligand and palladium-free avenue for cyanation of aryl Halides: The art of samarium powder in C–C coupling reaction

    , Article ChemistrySelect ; Volume 4, Issue 33 , 2019 , Pages 9618-9621 ; 23656549 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Gholamtajari, M ; Karimi, A ; Sharif University of Technology
    Wiley-Blackwell  2019
    This is the first study of samarium powder catalyzed cyanation reaction of aryl halides, bearing electron-withdrawing and electron-releasing substituents, in the presence of NaCN to afford corresponding benzonitriles in high yields. This protocol takes the advantage of being done in the absence of additive, ligand and precious transition metals such as palladium. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim  

    Reductive amination of aldehydes with sodium borohydride and lithium aluminum hydride in the presence of lithium perchlorate

    , Article Journal of the Iranian Chemical Society ; Volume 4, Issue 2 , 2007 , Pages 194-198 ; 1735207X (ISSN) Saidi, M. R ; Brown, R. S ; Ziyaei Halimjani, A ; Sharif University of Technology
    Iranian Chemical Society  2007
    A one-pot high yielding reductive amination of aldehydes with primary and secondary amines using LiClO4/NaBH4 and LiClO 4/LiAlH4 as reducing agents in diethyl ether is described  

    Room temperature catalytic aromatization of Hantzsch 1,4-dihydropyridines by sodium nitrite in the presence of acidic silica gel

    , Article Monatshefte fur Chemie ; Volume 137, Issue 2 , 2006 , Pages 197-200 ; 00269247 (ISSN) Hashemi, M. M ; Ghafuri, H ; Karimi Jaberi, Z ; Sharif University of Technology
    Various alkyl, aryl, and heterocyclic Hantzsch 1,4-dihydropyridines were converted to the corresponding pyridines in excellent yields and short times using sodium nitrite in the presence of a catalytic amount of acidic silica gel at room temperature. © Springer-Verlag 2006  

    Full-polysaccharide superabsorbent hydrogels based on carboxymethylcellulose and sodium alginate

    , Article Journal of Polymer Materials ; Volume 23, Issue 1 , 2006 , Pages 61-69 ; 09738622 (ISSN) Hosseinzadeh, H ; Pourjavadi, A ; Madhavinia, G. R ; Sharif University of Technology
    A novel full-polysaccharide superabsorbent hydrogel was synthesized via chemical crosslinking of carboxymethylcellulose (CMC) and sodium alginate (Alg) using epichlorohydrine (ECH) as a crosslinker. A proposed mechanism for hydrogel formation was suggested and the structure of the product was established using FTIR spectroscopy. The influence of ECH concentration and Alg/CMC weight ratio as well as reaction time and temperature on water and saline (0.9 wt% NaCl) absorbency of the hydrogels were systematically investigated. Meanwhile, the overall activation energy for the crosslinking reaction between CMC and Alg polysaccharides was estimated to be 11.6 kj/mol. Under the optimised conditions... 

    Sodium hypochlorite-Dowex 1X8-200: A convenient oxidizing reagant

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 21, Issue 2 , 2002 , Pages 71-73 ; 10219986 (ISSN) Mahmoodi Hashemi, M ; Ahmadibeni, Y ; Sharif University of Technology
    The polymer supported hypochlorite ion is a facile selective oxidizing agent for the oxidation of various alcohols to aldehydes and ketones. Similarly it successfully oxidizes various Hantzsch type 1,4 - dihydropyridines to corresponding pyridines  

    Influence of formulation parameters on the release of diclofenac sodium from matrices with manufacturing formulation ingredients

    , Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 21, Issue 2 , 2002 , Pages 135-140 ; 10219986 (ISSN) Abdekhodaie, M. J ; Hemmati, A. A ; Sharif University of Technology
    Effects of formulation parameters on the fractional release profile of diclofenac sodium from matrices having the manufacturing formulation ingredients are studied. As a content of cetyl alcohol (rate controlling agent) in the matrix increases, the fractional release decreases. The fractional release increases either by increasing sucrose content outside the granule or by decreasing sucrose content inside the granule. Results presented here indicate that as PVP content outside the granule or aerosil fraction inside or outside the granule in the matrix increases, the fractional release increases. The fractional release profiles of diclofenac sodium from matrices, when each ingredient is... 

    Oxidation of alcohols and primary aliphatic amines to carbonyl compounds using sodium hypochlorite adsorbed on montmorillonite K10

    , Article Journal of Chemical Research - Part S ; Issue 5 , 2000 , Pages 224-225 ; 03082342 (ISSN) Hashemi, M. M ; Beni, Y. A ; Sharif University of Technology
    Scientific Reviews Ltd  2000
    NaClO adsorbed on montmorillonite K10 converts alcohols and primary aliphatic amines into corresponding carbonyl compounds  

    Development of Magnetic Iron Oxide Nanoparticles Encapsulated in the Polymeric Matrix and its Applications in the Study of Radionuclides Uptake

    , M.Sc. Thesis Sharif University of Technology Esmailnia, Sahar (Author) ; Otukesh, Mohammad (Supervisor) ; Khanchi, Alireza (Supervisor)
    Nanoparticles have attracted the attention of many researchers because of the distinct physical and chemical properties. Besides the traditional applications in plastic reinforcement, fluid rheological additive, etc., the nanoparticles could be applied to many new fields and high-functional devices. Various chemical methods have been employed for the production of nanoparticles with narrow size distribution, such as co-precipitation, micro-emulsion, electrochemical synthesis, hydrothermal synthesis, sol–gel processing, flame spray pyrolysis, plasma chemical vapor deposition (CVD), hot-soap method and electrospray pyrolysis. But most of them have some problems so that only a few of them... 

    MBA-crosslinked Na-Alg/CMC as a smart full-polysaccharide superabsorbent hydrogels

    , Article Carbohydrate Polymers ; Volume 66, Issue 3 , 2006 , Pages 386-395 ; 01448617 (ISSN) Pourjavadi, A ; Barzegar, Sh ; Mahdavinia, G. R ; Sharif University of Technology
    A novel superabsorbent hydrogel composed of carboxymethylcellulose (CMC) and sodium alginate (Na-Alg) was prepared by using methylenebisacrylamide (MBA) as a crosslinking agent. Ammonium persulfate (APS) was used as an initiator. For investigation of the effect of reaction variables on water absorbency of the hydrogels, the synthetic conditions were systematically optimized through studying the influential factors, including temperature, Na-Alg/CMC weight ratio and concentration of MBA and APS. Increase in MBA and APS concentration results in the decrease in water absorbency of the hydrogels. The water absorbency of the hydrogels increased with increasing of reaction temperature and... 

    Effect of inhibitors on the corrosion of automotive aluminum alloy in ethylene glycol-water mixture

    , Article Corrosion ; Volume 67, Issue 12 , 2011 ; 00109312 (ISSN) Asadikiya, M ; Ghorbani, M ; Sharif University of Technology
    The effect of some inhibitors consisting of sodium nitrite (NaNO 2), sodium nitrate (NaNO 3), sodium molybdate (Na 2MoO 4), and sodium silicate (Na 2SiO 3) on the corrosion behavior of aluminum alloy 3303 (UNS A93303) in a water and ethylene glycol (C 2H 6O 2) mixture was investigated. In the first part, the tests were established without any galvanic coupling. In the second part, the tests were established with galvanic connections between the aluminum alloy and mild steel, stainless steel, copper, brass, and solder. Results show that the best corrosion inhibitor in both situations is sodium nitrate, according to its abilities to reduce corrosion rate, passivate the aluminum surface, and... 

    Investigating and modeling the cleaning-in-place process for retrieving the membrane permeate flux: Case study of hydrophilic polyethersulfone (PES)

    , Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 62 , May , 2016 , Pages 150–157 ; 18761070 (ISSN) Hedayati Moghaddam, A ; Shayegan, J ; Sargolzaei, J ; Sharif University of Technology
    Taiwan Institute of Chemical Engineers  2016
    In this work the effects of backwash pressure, duration of acid and sodium hydroxide backwashing, sodium hydroxide concentration, and the duration of forward washing on performance of permeate flux recovery (PFR) were investigated. A two-level fractional factorial design (FFD) was used to design the experiments. The ability of back propagation neural network (BPNN) and radial basis function neural network (RBFNN) in predicting the performance of cleaning-in-place (CIP) of hydrophilic polyethersulfone (PES) membrane were investigated. It is found that BPNN has better ability in predicting the PFR performance than RBFNN. The best architecture of BPNN was a network consisting of 1 hidden layer... 

    Magnetic stirring assisted hydrothermal synthesis of Na3MnCO3PO4 cathode material for sodium-ion battery

    , Article Ceramics International ; Volume 47, Issue 19 , 2021 , Pages 26929-26934 ; 02728842 (ISSN) Hassanzadeh, N ; Sadrnezhaad, S.K ; Sharif University of Technology
    Elsevier Ltd  2021
    Na3MnCO3PO4 (NMCP) is considered one of the promising cathode materials for sodium-ion batteries due to its high theoretical capacity. The hydrothermal method is an efficient, environmental-friendly, and simple route with low instrument cost to prepare active cathode materials such as NMCP. In this research, magnetic stirring was applied to promote the hydrothermal synthesis, and NMCP was produced by controlling different stirring times. This method results in the formation of pure NMCP upon only 45 min processing time. According to the ICP results, the Na to Mn ratio in the NMCP approached the stoichiometric value of 3 by prolonging the stirring time. By analyzing the charge-discharge... 

    Mechanical Characteristics of Activated Slag Concrete with Alkaline Solution

    , M.Sc. Thesis Sharif University of Technology Esmati, Ali (Author) ; Kazemi, Mohammad Taghi (Supervisor)
    Nowadays, due to the increasing importance of environmental issues, cement replacement has been considered by many researchers .Determination of behavioral characteristics and fracture of materials such as fracture hardness and energy is used to describe the formation and progress of cracks in new building materials. On the other hand, one of the concrete that can be replaced ordinary concrete is slag concrete. Slag concrete is in the category of Geopolymer Concrete. This concrete is produced by activation of puzzulanic material by alkaline solution.There have not been many studies on the failure of slag concrete. Therefore, in this study, the mechanical properties of slag concrete were...