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Application of a free volume model in correlating thermodynamic properties of β-lactam, tetracycline, fluoroquinolone and chloramphenicol antibiotic groups in associating fluids
, Article Chemical Engineering Research and Design ; Volume 87, Issue 3 , 2009 , Pages 335-342 ; 02638762 (ISSN) ; Taghikhani, V ; Vossoughi, M ; Alemzadeh, I ; Sharif University of Technology
2009
Abstract
In this work, an expression for the free volume Gibbs energy model based on the local composition concept (LCC) has been proposed in correlating the solubility, the partitioning and the surface tension of β-lactam, tetracycline, fluoroquinolone and chloramphenicol antibiotic groups in water, alcohol, ketone, trihalomethane, ether and ester solvent groups. Similar to the LCC models the proposed model has two combinatorial and residual terms. The extended Guggenheim model is used as combinatorial term and a new local composition-based model, which is the extended local area fraction NRTL-NRF model, is proposed for the residual term. The results obtained from the proposed model have been...
Bioconjugation of interferon-alpha molecules to lysine-capped gold nanoparticles for further drug delivery applications
, Article Journal of Dispersion Science and Technology ; Volume 29, Issue 8 , 2008 , Pages 1062-1065 ; 01932691 (ISSN) ; Vossoughi, M ; Almzadeh, I ; Zeinali, M ; Sharif University of Technology
2008
Abstract
Gold nanoparticles are potentially very attractive components for therapeutic delivery since they can be synthesized with any diameter from 1 to 200 nm to carry a payload of therapeutic molecules into a cell without triggering an immune response. Gold nanoparticles must undergo surface transformations before coupling to therapeutic molecules to become eligible for this purpose. It is now more understood that amine groups can bind to gold nanoparticles strongly, which has enabled surface modification of gold nanoparticles with amino acid lysine through its amine group. These lysine capped gold nanoparticles can further be coupled to therapeutic molecules for delivery purposes. In this study...
DFT/B3LYP study of thermochemistry of D-glucosamine, a representative polyfunctional bioorganic compound
, Article Scientia Iranica ; Volume 15, Issue 4 , 2008 , Pages 422-429 ; 10263098 (ISSN) ; Ghorat, M ; Pourjavadi, A ; Kurdtabar, M ; Torabi, A. A ; Sharif University of Technology
Sharif University of Technology
2008
Abstract
D-glucosamine, as a representative polyfunctional compound, is a bioactive amino sugar. In this study, the gas phase thermochemical properties of D-glucosamine, including its Metal Ion Affinity (MIA), metal binding sites, Anion Affinity (AA), acidity and proton affinity, have been explored, using the Density Functional Theory (DFT) and a 6-311++G**basis set. The summary of the MIA and AA results (in kcal/mol-1) are: Li+ = 67.6, Na+ = 51.1, K+ = 37.3, Mg2+ = 207.9, Ca2+ = 150.4, Zn2+ = 251.2, Cl- = 27.4, CN- = 28.0. The acidity values calculated at different sites, including four -OH groups and one -NH2 group, range from 344.0 to 373.0 kcal/mol-1. These results, surprisingly, indicate how...
Determining an optimum catalyst for liquid-phase dehydration of methanol to dimethyl ether
, Article Applied Catalysis A: General ; Volume 349, Issue 1-2 , 2008 , Pages 6-12 ; 0926860X (ISSN) ; Kazemeini, M ; Aghaziarati, M ; Sharif University of Technology
2008
Abstract
The liquid-phase dehydration of methanol to dimethyl ether was investigated over various materials including synthetic zeolites, namely, ZSM-5, Y, Mordenite, Ferrierite and Beta as well as silica and alumina. The key characters investigated were the Si/Al ratio and cation exchange. The results showed that the Mordenite zeolite exchanged with H+ exhibited the highest activity in dehydration of methanol. After finding the most active catalyst, the Mordenite zeolite was modified with Cu, Zn, Ni, Al, Zr, Mg and Na via wet-impregnation method to further improve its selectivity, and characterized by AAS, XRD, NH3-TPD, NH3-FT-IR and BET surface area techniques. It was found that these materials...
The photochromic switchable imidazoles: Their genesis, development, synthesis, and characterization
, Article Dyes and Pigments ; Volume 203 , 2022 ; 01437208 (ISSN) ; Mirzaee, M ; Hosseini, S ; Gholamzadeh, P ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Switchable photochromic dyes have benefited greatly from the use of heterocyclic chemicals. The imidazole group is particularly essential because it can be transformed into dimers, which can then be radicalized in the presence of light photons. Imidazole dimers have been optimized throughout thirty years of research, allowing derivatives with diverse colors, quick reversibility, and sensitivity to different wavelengths from UV to near IR ranges. These imidazole dimers are interesting to be used in the matrices of polymers, hydrogels, glasses, solar cells, and even pharmaceuticals. The goal of this review is to look at the history, development, and future of imidazole dimers. We will also...
Perylene diimide-POSS network for semi selective solid-phase microextraction of lung cancer biomarkers in exhaled breath
, Article Analytica Chimica Acta ; Volume 1198 , 2022 ; 00032670 (ISSN) ; Bagheri, H ; Yeganeh Rad, L ; Minaeian, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Lung cancer (LC) is the leading cause of cancer mortality so, the analysis of exhaled human breath has great significance for early non-invasive diagnosis. Poor selectivity and strong humidity are two bottlenecks for the application of gas sensors to exhaled breath analysis. The development of novel extractive phases for the analysis of exhaled breath by chromatography is therefore a lucrative object. Polyhedral oligomeric silsesquioxanes (POSS) are among the 3D porous materials whose unique properties make them promising coatings for solid-phase microextraction (SPME). Selective enrichment of polar or nonpolar targets depends on the pore size and functional groups on the POSSs. Herein, we...
A selective chemiresistive sensor for the cancer-related volatile organic compound hexanal by using molecularly imprinted polymers and multiwalled carbon nanotubes
, Article Microchimica Acta ; Volume 186, Issue 3 , 2019 ; 00263672 (ISSN) ; Banan Nojavani, M ; Nikkhah, M ; Alizadeh, T ; Esfandiar, A ; Ganjali, M. R ; Sharif University of Technology
Springer-Verlag Wien
2019
Abstract
A chemiresistive sensor is described for the lung cancer biomarker hexanal. A composite consisting of molecularly imprinted polymer nanoparticles and multiwalled carbon nanotubes was used in the sensor that is typically operated at a voltage of 4 V and is capable of selectively sensing gaseous hexanal at room temperature. It works in the 10 to 200 ppm concentration range and has a 10 ppm detection limit (at S/N = 3). The sensor signal recovers to a value close to its starting value without the need for heating even after exposure to relatively high levels of hexanal
Amine/phenyl gradient derived base layer as a comprehensive extractive phase for headspace cooled in–tube microextraction of volatile organic compounds in saliva
, Article Journal of Pharmaceutical and Biomedical Analysis ; Volume 191 , 2020 ; Bagheri, H ; Rostami, A ; Sharif University of Technology
Elsevier B.V
2020
Abstract
A gradient derived base layer extractive phase was synthesized and applied for the determination of volatile organic compounds (VOCs) in saliva samples using the headspace cooled in–tube microextraction (HS–CITME) method. The base layers from three different sols of phenyltriethoxysilane (PTES), octyltrimethoxysilane (OTMS) and methyltrimethoxysilane (MTMS) as nonpolar precursors were individually dip coated on the stainless steel wires (SSW). Then, the hydrolyzed polar precursor aminopropyltriethoxysilane (APTES) reacted with the silanol groups already formed on the surface of SSWs via controlled rate infusion (CRI) method. The presence of polar and non–polar functional groups on the...
A core–shell titanium dioxide polyaniline nanocomposite for the needle-trap extraction of volatile organic compounds in urine samples
, Article Journal of Separation Science ; Volume 40, Issue 9 , 2017 , Pages 1985-1992 ; 16159306 (ISSN) ; Bagheri, H ; Sharif University of Technology
Wiley-VCH Verlag
2017
Abstract
We synthesized a titanium dioxide–polyaniline core–shell nanocomposite and implemented it as an efficient sorbent for the needle-trap extraction of some volatile organic compounds from urine samples. Polyaniline was synthesized, in the form of the emeraldine base, dissolved in dimethyl acetamide followed by diluting with water at pH 2.8, using the interfacial polymerization method. The TiO2 nanoparticles were encapsulated inside the conducting polymer shell, by adapting the in situ dispersing approach. The surface characteristics of the nanocomposite were investigated by Fourier transform infrared spectrometry, scanning electron microscopy, and transmission electron microscopy. After...
A systematic review of land use regression models for volatile organic compounds
, Article Atmospheric Environment ; Volume 171 , 2017 , Pages 1-16 ; 13522310 (ISSN) ; Yunesian, M ; Hosseini, V ; Schindler, C ; Henderson, S. B ; Künzli, N ; Sharif University of Technology
Abstract
Various aspects of land use regression (LUR) models for volatile organic compounds (VOCs) were systematically reviewed. Sixteen studies were identified published between 2002 and 2017. Of these, six were conducted in Canada, five in the USA, two in Spain, and one each in Germany, Italy, and Iran. They were developed for 14 different individual VOCs or groupings: benzene; toluene; ethylbenzene; m-xylene; p-xylene; (m/p)-xylene; o-xylene; total BTEX; 1,3-butadiene; formaldehyde; n-hexane; total hydro carbons; styrene; and acrolein. The models were based on measurements ranging from 22 sites in El Paso (USA) to 179 sites in Tehran (Iran). Only four studies in Rome (Italy), Sabadell (Spain),...
Modeling Secondary Organic Aerosol Formation from Fuel Combustion and Evaporation, Using Box Model and Primary and Secondary Source Apportionment of Fine Particulate Matter, Using PMF Receptor Model
, Ph.D. Dissertation Sharif University of Technology ; Hosseini, Vahid (Supervisor) ; Shamloo, Amir (Co-Supervisor)
Abstract
Focus of the present research is on the study and cognition of sources of carbonaceous compounds present in PM2.5, particularly secondary organic carbon. For this purpose, two different approaches were used. The first approach investigates the SOA formation from internal combustion engines exhaust and unburned fuel (bottom-up approach). The second approach studies the contribution of each of the primary and secondary sources to PM2.5 mass, whereby secondary organic carbon share is obtained (top-down approach). Modeling SOA formation from vehicles exhaust showed that diesel vehicles have greater SOA formation potential than gasoline vehicles, due to large amount of S/IVOCs present in their...
Adsorption of petroleum monoaromatics from aqueous solutions using granulated surface modified natural nanozeolites: Systematic study of equilibrium isotherms
, Article Water, Air, and Soil Pollution ; Volume 217, Issue 1-4 , 2011 , Pages 611-625 ; 00496979 (ISSN) ; Torabian, A ; Kazemian, H ; Bidhendi, G. N ; Azimi, A. A ; Charkhi, A ; Sharif University of Technology
Abstract
Petroleum monoaromatics including benzene, toluene, ethylbenzene, and xylenes (BTEX) are among the notorious volatile organic compounds that contaminate water and soil. In this study, a surfactant- modified natural zeolite and its relevant granulated nanozeolites were evaluated as potential adsorbents for removal of petroleum monoaromatics from aqueous solutions. All experiments performed in batch mode at constant temperature of 20°C and pH of 6.8 for 48 h. The results revealed that the amount of BTEX uptake on granulated zeolites nanoparticles were remarkably higher than the parent micron size natural zeolite (in the order of four times). The isotherms data were analyzed using five models...
Roles of inorganic oxide nanoparticles on extraction efficiency of electrospun polyethylene terephthalate nanocomposite as an unbreakable fiber coating
, Article Journal of Chromatography A ; Volume 1375 , 2015 , Pages 8-16 ; 00219673 (ISSN) ; Roostaie, A ; Sharif University of Technology
Elsevier
2015
Abstract
In the present work, the roles of inorganic oxide nanoparticles on the extraction efficiency of polyethylene terephthalate-based nanocomposites were extensively studied. Four fiber coatings based on polyethylene terephthalate nanocomposites containing different types of nanoparticles along with a pristine polyethylene terephthalate polymer were conveniently electrospun on stainless steel wires. The applicability of new fiber coatings were examined by headspace-solid phase microextraction of some environmentally important volatile organic compound such as benzene, toluene, ethylbenzene and xylene (BTEX), as model compounds, from aqueous samples. Subsequently, the extracted analytes were...
Gradient extractive phase prepared by controlled rate infusion method: An applicable approach in solid phase microextraction for non–targeted analysis
, Article Journal of Chromatography A ; Volume 1574 , 2018 , Pages 130-135 ; 00219673 (ISSN) ; Kazemi, E ; Bagheri, H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
The aim of this study is to introduce an extractive phase based on gradient concept by continuous changing in chemical functional groups for non–targeted analysis. For this purpose, three different two–component coatings containing (3–aminopropyl)trimethoxysilane (APTES) as polar and either phenyltriethoxysilane (PTES), octyl–trimethoxysilane (OTMS) or methyltrimethoxysilane (MTMS) as nonpolar precursors were formed on the modified stainless steel wires using controlled rate infusion (CRI) method. The presence of polar and/or non–polar functional groups on the surface of substrate was evaluated by Fourier–transform infrared spectroscopy (FTIR) together with contact angles determined...
Source Apportionment of Air Particulate Matter (PM2.5)in Tehran Using CMB Model
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
In recent years, one of the most important air pollution in Tehran in terms of creating unhealthy air quality is particulate matter and especially PM2.5. Particulate matter in Tehran is released from various sources. Identification of components and estimating the contribution of each emission sources, helps governers to find air pollution control strategies. To find out major components of PM2.5 in Tehran, a one year sampling to collect PM2.5 was conducted from February 2014 through February 2015 in AQM station at Sharif University of Technology located west of Tehran. 24-hour integrated samples collected on a 1-in-6 day schedule on both Teflon and quartz filters. TOT analysis was done for...
Experimental Study of Formaldehyde Decomposition Using a Plasma - Catalyst Hybrid Reactor as a Potential Voc Removal Technique
,
M.Sc. Thesis
Sharif University of Technology
;
Hamzeh Louyan, Tayyebeh
(Supervisor)
;
Khani, Mohammad Reza
(Supervisor)
Abstract
Volatile organic compounds (VOCs) has harmful environmental and health effects and appropriate processes are needed to remove them from industrial and indoor environments. In this study, formaldehyde as one of the most toxic VOCs was investigated. Various methods have been developed to remove formaldehyde, however due to the to their low removal efficiencies, secondary pollution, and low energy efficiency, development of alternative methods will be beneficial. In recent years, the use of a combination of non-thermal plasma and catalyst technologies, called plasma-catalytic hybrid reactors, has provided significant results in the fields of chemical synthesis and removal of pollutants. In the...
Chemometrics-assisted GC-MS analysis of volatile and semi-volatile constituents of elettaria cardamomum
, Article Food Analytical Methods ; Vol. 7, issue. 9 , 2014 , pp. 1745-1754 ; ISSN: 1936-9751 ; Mani-Varnosfaderani, A ; Sharif University of Technology
Abstract
Multivariate curve resolutions (MCR) along with other chemometric techniques are proposed to improve the analysis of Iranian Elettaria cardamomum (E. cardamom) essential oil with gas chromatography-mass spectrometry (GC-MS). In addition, multivariate curve resolution-alternating least squares (MCR-ALS) is used to obtain pure elution and mass spectral profiles for the components present in each chromatographic segment as well as their relative concentrations. This strategy was also used to overcome the problems of baseline offset, asymmetric peaks, retention time shifts, and overlapped and embedded peaks occurring during GC-MS analysis. The analysis of GC-MS data revealed that 42 components...
Modeling the kinetics of asphaltene flocculation in toluene-pentane systems for the case of sonicated crude oils
, Article Scientia Iranica ; Volume 20, Issue 3 , June , 2013 , Pages 611-616 ; 10263098 (ISSN) ; Tavakolian, M ; Najafi, I ; Ghazanfari, M. H ; Taghikhania, V ; Amani, M ; Sharif University of Technology
2013
Abstract
This work is concerned with the monitoring of ultrasound effects on inhibition, as well as the reversible kinetics modeling of asphaltene flocculation in toluene-n-alkane systems, which has been rarely reported in the literature. A crude oil sample was exposed to ultrasound waves, and then the colloidal structural evolutions of flocculated asphaltene particles induced by addition of n-alkane were studied, using a confocal microscopy. Observations confirmed that radiation of ultrasound can change the irreversibility of asphaltene flocculation in crude oil. To interpret the kinetics of asphaltene flock aggregation, the Smoluchowski model was used, and the time dependent size distribution of...
Ionic modified crosslinked salep: A highly loaded and efficient heterogeneous organocatalyst
, Article Carbohydrate Polymers ; Volume 92, Issue 2 , 2013 , Pages 2252-2256 ; 01448617 (ISSN) ; Hosseini, S. H ; Fakoorpoor, S. M ; Sharif University of Technology
2013
Abstract
In this work, a novel heterogeneous organocatalyst was synthesized by immobilization of hydroxide ions on the modified salep as a natural polymer. Because of the grafting of ionic polymer chains onto the salep backbone, catalyst has high loading level of hydroxide ions (3.01 mmol/g). The resulting catalyst shows excellent activity in the synthesis of 4H-benzo[b]pyrans in water at room temperature in short reaction times. The present catalyst and protocol represent a simple, ecologically safe and cost-effective route to synthesize 4H-benzo[b]pyrans with high product yield, as well as easy catalyst recycling
A green protocol for Erlenmeyer-Plöchl reaction by using iron oxide nanoparticles under ultra sonic irradiation
, Article Ultrasonics Sonochemistry ; Volume 20, Issue 1 , 2013 , Pages 408-412 ; 13504177 (ISSN) ; Sadjadi, S ; Hosseinpour, M ; Sharif University of Technology
2013
Abstract
Azlactones have been prepared via Erlenmeyer synthesis from aromatic aldehydes and hippuric acid using Fe 2O 3 nanoparticles under ultrasonic irradiation. Short reaction times, easy and quick isolation of the products, and excellent yields are the main advantages of this procedure