Sharif University of TechnologyScientia Iranica1026-309821320140601Spectrophotometric determination of paracetamol using Hydrogel based semi solid-liquid dispersive microextractionSpectrophotometric determination of paracetamol using Hydrogel based semi solid-liquid dispersive microextraction6937023506ENNaimeh MohseniDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranMorteza BahramDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranKhalil FarhadiDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranPeyman Najafi-MoghaddamDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranForoogh KeshvariDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, IranJournal Article20130804A simple, fast and inexpensive method based on dispersive liquid-liquid microextraction (DLLME) and dispersive solid-phase extraction (DSPE) has been developed for preconcentration and spectrophotometric determination of paracetamol (PC) using pH-sensitive hydrogel (HG). In this study we demonstrate a novel microextraction technique, entitled “semi solid-liquid dispersive microextraction” which can be successfully used for preconcentration of analytes of interest from aqueous samples. The procedure involves the oxidation of paracetamol by Fe(III) and a subsequent reaction with ferricyanide in the presence of HCl to yield Prussian Blue (PB) complex. In the extraction step, appropriate amounts of poly(styrene-alt-maleic anhydride), as a pH-sensitive hyrogel, was injected into the aqueous solution, so a cloudy solution was formed. Organic and inorganic compounds having the potential to interact with polymer particles could be extracted into the organic phase. For our case PB complex could be extracted to the cloudy phase. After centrifugating, the hydrogel-rich phase was sedimented at the bottom of centrifuge tube. The absorbance of the sedimented phase diluted in methanol was measured at the absorption maximum of 733 nm (λmax of PB in hydrogel). The absorbance was linear to paracetamol concentration in the range of 0.01-0.5 μg mL-1 with a correlation coefficient of 0.995.Sharif University of TechnologyScientia Iranica1026-309821320140601An Efficient, Three-Component Synthesis of 1-Aryl-2,3-Dihydro-3-Phenyl- 1H- Naphth[1,2-e][1,3]Oxazines Derivatives; Using LaCl3/ClCH2COOH as Environmentally Benign and Green Catalytic SystemAn Efficient, Three-Component Synthesis of 1-Aryl-2,3-Dihydro-3-Phenyl- 1H- Naphth[1,2-e][1,3]Oxazines Derivatives; Using LaCl3/ClCH2COOH as Environmentally Benign and Green Catalytic System7037073507ENBehjat PouramiriDepartment of Chemistry, Faculty of Science, Shahid Bahonar University, P.O. Box 76169, Kerman, IranEsmat Tavakolinejad KermaniDepartment of Chemistry, Faculty of Science, Shahid Bahonar University, P.O. Box 76169, Kerman, IranJournal Article201312111-Aryl-2,3-dihydro-3-phenyl-1H-naphth[1,2-e][1,3]oxazines are synthesized in good to excellent yields in the presence of LaCl3/ClCH2COOH as an inexpensive and environmentally benign catalytic system under solvent-free conditions.Sharif University of TechnologyScientia Iranica1026-309821320140601Silica supported boron trifluoride nanoparticles(BF3-SiO2 NPs): An efficient and reusable catalyst for one-pot synthesis of benzo[a]xanthene-11-onederivativesSilica supported boron trifluoride nanoparticles(BF3-SiO2 NPs): An efficient and reusable catalyst for one-pot synthesis of benzo[a]xanthene-11-onederivatives7087143508ENB. SadeghiDepartment of Chemistry, Yazd Branch, Islamic Azad University, P.O.Box 89195-155, Yazd, IranJournal Article20140120Silica supported boron trifluoride nanoparticles(BF3-SiO2 NPs) as a mild solid acid catalyst has been used for an improved and rapid one-pot synthesis of benzo[a]xanthene-11-onederivatives using EtOH as a reaction medium. This Michael addition of various aromatic aldehydes with 2-naphtholand dimedone is very simple and the products are isolated with a .......Sharif University of TechnologyScientia Iranica1026-309821320140601Dielectric Analysis of Novel Bipodal and Tripodal Piperidin-4-onesDielectric Analysis of Novel Bipodal and Tripodal Piperidin-4-ones7157183509ENK. RajeshCentre for Organic and Medicinal Chemistry, VIT University, Vellore-632014, Tamil Nadu, IndiaV. VijayakumarCentre for Organic and Medicinal Chemistry, VIT University, Vellore-632014, Tamil Nadu, IndiaB. Palakshi ReddyCentre for Organic and Medicinal Chemistry, VIT University, Vellore-632014, Tamil Nadu, IndiaS. SarveswariCentre for Organic and Medicinal Chemistry, VIT University, Vellore-632014, Tamil Nadu, IndiaJournal Article20130804Novel bipodal, tripodalpiperidin-4-ones and their corresponding piperidin-4-ols were subjected to dielectric analysis which signifies drug delivery. The studies revealed that these compounds can exhibit better drug release in association with polymer.Sharif University of TechnologyScientia Iranica1026-309821320140601An efficient synthesis of monoarylidene derivatives of pyran-4-one and piperidin-4-oneAn efficient synthesis of monoarylidene derivatives of pyran-4-one and piperidin-4-one7197263510ENMohammad M. MojtahediChemistry and Chemical Engineering Research Center of Iran P.O.Box 14335-186, Tehran, IranM. Saeed AbaeeChemistry and Chemical Engineering Research Center of Iran P.O.Box 14335-186, Tehran, IranMaedeh SamianifardChemistry and Chemical Engineering Research Center of Iran P.O.Box 14335-186, Tehran, IranAkram ShamlooChemistry and Chemical Engineering Research Center of Iran P.O.Box 14335-186, Tehran, IranJournal Article20140223A room-temperature procedure is developed for the direct synthesis of monoarylidene derivatives of pyran-4-one and piperidin-4-one systems under solvent-free conditions. Relatively high yields of products are obtained from the reaction of ketones 1 with different aromatic and aliphatic aldehydes under the catalytic system of TMSNMe2 and MgBr2·OEt2. Notably, formation of the undesired bis counterparts as a major limitation of these reaction types, is minimized using the employed conditions.Sharif University of TechnologyScientia Iranica1026-309821320140601Preparation of 1-(benzothiazolylamino)methyl -2-naphthols using multi-SO3H functionalized ionic liquid under solvent-free conditionsPreparation of 1-(benzothiazolylamino)methyl -2-naphthols using multi-SO3H functionalized ionic liquid under solvent-free conditions7277343511ENH.R. ShaterianDepartment of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, P.O. Box 98 135-674, Iran.A. HosseinianDepartment of Chemistry, Faculty of Sciences, University of Sistan and Baluchestan, Zahedan, P.O. Box 98 135-674, Iran.Journal Article20140701A one-pot, three-component condensation of aldehydes, 2-naphthol and 2- aminobenzothiazole in the presence of multi-SO3H functionalized ionic liquid (synthesized from hexamethylenetetramine and 1,4-butane sulfonate), as an eective catalyst for the synthesis of 1-(benzothiazolylamino)methyl-2-naphthol derivatives, under thermal and solvent-free conditions, is described. These products involve two biologically active parts; Betti's base and benzothiazole. The present methodology oers several advantages, such as good yields, short reaction times, and easy work-up. The catalyst could be recycled and reused without substantial reduction in its catalytic activitiesSharif University of TechnologyScientia Iranica1026-309821320140601Solvent-free synthesis of -benzylpyrano[3,2-c]pyran/chromene-2,5-diones via tandem reaction of 4-hydroxy-6-methyl-pyran-2-one and 4-hydroxycoumarin with Baylis-Hillman adduct acetatesSolvent-free synthesis of -benzylpyrano[3,2-c]pyran/chromene-2,5-diones via tandem reaction of 4-hydroxy-6-methyl-pyran-2-one and 4-hydroxycoumarin with Baylis-Hillman adduct acetates7357413512ENF. Matloubi MoghaddamLaboratory of Organic Synthesis and Natural Products, Department of Chemistry, Sharif University of Technology, Tehran, P. O. Box: 11155-9516, IranB. Koushki ForoushaniLaboratory of Organic Synthesis and Natural Products, Department of Chemistry, Sharif University of Technology, Tehran, P. O. Box: 11155-9516, Iran.E. Lotfi KalahroodiLaboratory of Organic Synthesis and Natural Products, Department of Chemistry, Sharif University of Technology, Tehran, P. O. Box: 11155-9516, IranJournal Article201407014-hydroxycoumarin 2a and 4-hydroxy-6-methyl-pyran-2-one 2b were applied in a one-pot reaction with Baylis-Hillman adduct acetates 1 to form novel 3-benzylpyrano [3, 2-c] pyran-2, 5-diones 3 in high yields (70-85%). The synthesized framework isavailable in many biologically active moieties. The reaction was carried out under dierent conditions to achieve optimum conditions. The results indicated that Et3N, as a base under solvent-free conditions, was optimum. The reaction procedure and purication method are mild and straightforward.Sharif University of TechnologyScientia Iranica1026-309821320140601A facile and green three-component synthesis of 2-amino-3-cyano-7-hydroxy-4H-chromenes on grindingA facile and green three-component synthesis of 2-amino-3-cyano-7-hydroxy-4H-chromenes on grinding7427473513ENShahrzad JavanshirDepartment of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, IranMostafa SafariDepartment of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, IranMohammad G. DekaminDepartment of Chemistry, Iran University of Science and Technology, Tehran 16846-13114, IranJournal Article20131111A simple, efficient and one-pot method has been developed for the synthesis of densely functionalized aryl derivatives of 2-amino-3-cyano-7-hydroxy-4H-chromene by the domino Knoevenagel-Michael-cyclization reactions of aromatic aldehydes, resorcinol and malononitrile in the presence of a catalytic amount of Na2CO3 under grinding conditions.Sharif University of TechnologyScientia Iranica1026-309821320140601A novel un-catalyzed and solvent-free method for the synthesis of 2-thioxothiazolidin-4-onesA novel un-catalyzed and solvent-free method for the synthesis of 2-thioxothiazolidin-4-ones7487513514ENSetareh MoghimiDepartment of Chemistry, School of Science, Alzahra University, PO Box 1993891176, Vanak, Tehran, IranMajid M. HeraviDepartment of Chemistry, School of Science, Alzahra University, PO Box 1993891176, Vanak, Tehran, IranHossein A. OskooieDepartment of Chemistry, School of Science, Alzahra University, PO Box 1993891176, Vanak, Tehran, IranYahya S. BeheshtihaDepartment of Chemistry, School of Science, Alzahra University, PO Box 1993891176, Vanak, Tehran, IranJournal Article20130805An easy and highly efficient one-pot, three-component synthesis of rhodanines is reported. The reaction of primary amines, carbon disulfide and chloroacetyl chloride proceeded in the absence of solvent and catalyst, to afford 2-thioxothiazolidin-4-ones in good to excellent yields.Sharif University of TechnologyScientia Iranica1026-309821320140601Experimental study of CO2 hydrate formation kinetics with and without kinetic and thermodynamic promotersExperimental study of CO2 hydrate formation kinetics with and without kinetic and thermodynamic promoters7537623515ENH. RoostaaSchool of Chemical, Gas and Petroleum Engineering, Semnan University, Semnan, IranF. VaraminianSchool of Chemical, Gas and Petroleum Engineering, Semnan University, Semnan, IranSh. KhosharaySchool of Chemical, Gas and Petroleum Engineering, Semnan University, Semnan, IranJournal Article20131023In this work, an experimental study of CO2 hydrate formation kinetics was performed. The effects of the stirring rate and initial pressure on the hydrate formation rate were investigated. The results showed that a stirring rate of 600 rpm was optimum for increasing the CO2hydrate formation rate, especiallyat lower temperatures. The effects of additives on the hydrate formation rate were also investigated. Three surfactants, sodium dodecyl sulfate (SDS), dodecyl trimethyl ammonium bromide (DTAB) and TritonX-100 (TX-100) were tested. DTAB and TX-100 were new surfactants for investigation on CO2 hydrate formation kinetics. SDS and DTAB did not significantly affect the hydrate formation rate at concentrations of 300 and 500 ppm, whereas SDS increased and DTAB insignificantly decreased the hydrate formation rate at 1000 ppm. Furthermore, TX-100 negligibly decreased the hydrate formation rate at 300 and 500 ppm, but significantly decreased the rate at 1000 ppm. In contrast, the application of thermodynamic additives, tetrahydrofuran (THF) and tetra-n-butyl ammonium bromide (TBAB) at low concentrations increased the hydrate formation rate, and these additives affectedthe rate of hydrate formation in a manner similar to kinetic promoters.Sharif University of TechnologyScientia Iranica1026-309821320140601Investigating the Role of Ultrasonic Wave on Two-Phase Relative Permeability in Free Gravity Drainage ProcessInvestigating the Role of Ultrasonic Wave on Two-Phase Relative Permeability in Free Gravity Drainage Process7637713516ENBehnam KeshavarziUltrasonic Research Group, Sharif University of Technology, Tehran, IranRahim KarimiUltrasonic Research Group, Sharif University of Technology, Tehran, IranIman NajafiUltrasonic Research Group, Sharif University of Technology, Tehran, IranCyrus GhotbiUltrasonic Research Group, Sharif University of Technology, Tehran, IranMohammad Hossein GhazanfariUltrasonic Research Group, Sharif University of Technology, Tehran, IranJournal Article20131023In this work, the process of free gravity drainage under the influence of ultrasonic waves was investigated. A glass bead pack porous medium was used to perform the free fall gravity drainage experiments. The tests were performed in presence and absence of ultrasonic waves and the data of recovery were recorded versus time in both conditions. The wetting phases relative permeability curve were obtained using the data of recovery versus time based on the Hagoort backward methodology and afterward, using the wetting phase relative permeability curve, the relative permeability of non-wetting phases were calculated by performing history matching to the experimental production data. The results revealed that ultrasound considerably increases the recovery factor of the free gravity drainage process. It was also observed that the relative permeability of both wetting and non-wetting phases increases under exposure to ultrasonic waves. The results of this work can be helpful to better understanding/evaluating the behavior of relative permeability curves of both wetting and non-wetting phases during free gravity drainage process under the exposure to ultrasonic wave.Sharif University of TechnologyScientia Iranica1026-309821320140601Removal of Zirconium from Aqueous Solution by Aspergillus nigerRemoval of Zirconium from Aqueous Solution by Aspergillus niger7727803517ENHamed Kalantari Department of Chemical and Petroleum Engineering, Sharif University of Technology, P.O.Box 11365-8639, Tehran, IranSoheila YaghmaeiDepartment of Chemical and Petroleum Engineering, Sharif University of Technology, P.O.Box 11365-8639, Tehran, IranReza RoostaazadDepartment of Chemical and Petroleum Engineering, Sharif University of Technology, P.O.Box 11365-8639, Tehran, IranHossein Mohammad-BeigiDepartment of Chemical and Petroleum Engineering, Sharif University of Technology, P.O.Box 11365-8639, Tehran, IranJournal Article20131125Removal of zirconium from its dilute aqueous solution by using Aspergillus niger as dried and living biomass was investigated. Through that, the effect of some operational parameters including pH, temperature, contact time, initial concentration of zirconium, and dose of biomass on biosorption were studied. Based on the results, it was concluded that the uptake of zirconium by both dried and living biomasses is pH dependent, and maximum uptake was observed in pH=3.1 for both biomasses. The maximum uptake capacity of living biomass was obtained in 30 OC. However, the biosorption of zirconium by dried biomass was not affected by temperature. The maximum uptake capacity for living and dried biomasses (78.8 mg/g and 142 mg/g, respectively) was obtained at equilibrium time of 120 min and 30 min, respectively. Equilibrium isotherms showed that adsorption of zirconium by living biomass follows Freundlich model and uptake of dried biomass follows Langmuir model. Kinetic studies showed that both kinds of biomasses follow second order model of kinetic.Sharif University of TechnologyScientia Iranica1026-309821320140601Estimation of Naturally Fractured Oil Reservoir Properties Using Material Balance MethodEstimation of Naturally Fractured Oil Reservoir Properties Using Material Balance Method7817913518ENNader EbrahimiScience and Research Branch, Islamic Azad University, Tehran, IranSaeid JamshidiDepartment of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, P.O. Box: 11155-9465, IranSajjad GholinejadDepartment of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, P.O. Box: 11155-9465, IranJournal Article20140126In fractured reservoirs, large variation of permeability due to the presence of fractures leads to the changes in production mechanism comparing to the conventional reservoirs. Hence, an appropriate model with ability to describe the reservoir properly can provide a more confident prediction of the future performance of the reservoir. One of the features of a representative model is the number and height of matrix blocks. The determination of these two parameters is one of the decisive steps in the calculation of an accurate amount of oil production from these reservoirs. In fact, matrix height shows its effect as a gravity force, which is one of the driving mechanisms. If the matrix height is less than the threshold height, it will have a significant influence on production. The aim of this study is therefore to obtain mathematical relations that are able to estimate the matrix height from material balance analysis. In this study: (a) The Havlena and Odeh’s straight line form of the material balance equation has been extended to analyze the behavior of naturally fractured reservoirs and (b) Equations that can be used to estimate the matrix height are obtained for the Warren-Root and Kazemi models.Sharif University of TechnologyScientia Iranica1026-309821320140601Effects of Breadfruit Seed Hull Ash Particles on Microstructures and Properties of Recycled Low Density Polyethylene/Breadfruit Seed Hull Ash CompositesEffects of Breadfruit Seed Hull Ash Particles on Microstructures and Properties of Recycled Low Density Polyethylene/Breadfruit Seed Hull Ash Composites7928023519ENC. U . AtuanyaaDepartment of Metallurgical and Materials Engineering, Namdi Azikiwe University, Awka, Anambra state, NigeriaS. C . Nwaigbob Department of Mechanical Engineering, Namdi Azikiwe University, Awka, Anambra state, NigeriaP. K . IgbokwecDepartment of Chemical Engineering, Namdi Azikiwe University, Awka, Anambra state, NigeriaJournal Article20140413Renewable resources such as natural fillers in reinforced materials with their new range of applications represent an important basis of fulfilling the ecological objective of creating environmental friendly materials. Study on composites using breadfruit seed hull ash particles (BFSHAp) as a reinforcing material and recycled low-density polyethylene (RLDPE) as a novel matrix has been made. The composites were produced by varying the breadfruit seed hull ash particles from 5-25wt% and the properties studied using mechanical tests and microstructural analysis. The results show that there was a uniform distribution of the breadfruit seed hull ash particles in the microstructure of RLDPE composites which is the major factor responsible for the improvement in the mechanical properties