Search for: aromatic-hydrocarbons
Total 70 records
Pyrrole-based conductive polymer as the solid-phase extraction medium for the preconcentration of environmental pollutants in water samples followed by gas chromatography with flame ionization and mass spectrometry detection, Article Journal of Chromatography A ; Volume 1015, Issue 1-2 , 2003 , Pages 23-30 ; 00219673 (ISSN) ; Mohammadi, A ; Sharif University of Technology
A pyrrole-based polymer was synthesized and applied as a new sorbent for solid-phase extraction (SPE) of some environmental pollutants from water samples. Polypyrrole (PPy) was synthesized by chemical oxidation of the monomer in nonaqueous solution. SPE of selected phenols, pesticides, and polyaromatic hydrocarbons (PAHs) from aqueous samples were performed using 200mg PPy. The determination was subsequently carried out by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The polymer showed much higher recoveries for aromatic compounds than aliphatics. Preconcentration of sample volumes up 1l led to acceptable recoveries for aromatic and...
Fabrication and characterization of high-branched recyclable PAMAM dendrimer polymers on the modified magnetic nanoparticles for removing naphthalene from aqueous solutions, Article Microchemical Journal ; Volume 145 , 2019 , Pages 767-777 ; 0026265X (ISSN) ; Hassani, A. H ; Panahi, H. A ; Borghei, S. M ; Sharif University of Technology
Elsevier Inc 2019
In this study, magnetic nanoparticles (MNPs) modified with poly amidoamine (PAMAM) dendrimers - by adding methyl acrylate and ethylenediamine continuously till 10th generation- which further anchored to benzaldehyde ligand through polymeric bonding and studied as a novel method for synthesizing a nano sorbent for removing naphthalene (NAP) from aqueous environments. Synthesized nanopolymer was characterized by Fourier transform infrared spectroscopy (FTIR), Field-Emission Scanning Electron Microscopy (FE-SEM) equipped with EDS, X-ray Diffraction (XRD), Vibrating Sample Magnetometry (VSM), thermal gravimetric analysis (TGA). Based on the obtained analysis results synthesized average...
Coupling of a modified in-tube solid phase microextraction technique with high performance liquid chromatography-fluorescence detection for the ultra-trace determination of polycyclic aromatic hydrocarbons in water samples, Article Chromatographia ; Volume 59, Issue 7-8 , 2004 , Pages 501-505 ; 00095893 (ISSN) ; Salemi, A ; Sharif University of Technology
Friedr. Vieweg und Sohn Verlags GmbH 2004
A modified in-tube solid phase microextraction (SPME) technique in conjunction with a high performance liquid chromatography (HPLC) was developed for the trace determination of polycyclic aromatic hydrocarbons (PAHs) in water samples. The extraction device contained a regular HPLC syringe, replacing the metallic needle by two concentric fused silica capillary tubes. The capillary tubes were coated with polydimethylsiloxane (PDMS) as the sorbent and were attached to the syringe by a homemade interface made from polyether ether ketone (PEEK). The sorption of analytes was achieved by frequent withdrawing and ejecting the water sample from/into a vial via the capillary tubes. For the desorption...
Multivariate analytical figures of merit as a metric for evaluation of quantitative measurements using comprehensive two-dimensional gas chromatography–mass spectrometry, Article Journal of Chromatography A ; Volume 1466 , 2016 , Pages 155-165 ; 00219673 (ISSN) ; Parastar, H ; Sharif University of Technology
The present contribution is devoted to develop multivariate analytical figures of merit (AFOMs) as a new metric for evaluation of quantitative measurements using comprehensive two-dimensional gas chromatography–mass spectrometry (GC × GC–MS). In this regard, new definition of sensitivity (SEN) is extended to GC × GC–MS data and then, other multivariate AFOMs including analytical SEN (γ), selectivity (SEL) and limit of detection (LOD) are calculated. Also, two frequently used second- and third-order calibration algorithms of multivariate curve resolution-alternating least squares (MCR-ALS) as representative of multi-set methods and parallel factor analysis (PARAFAC) as representative of...
Article Tenside, Surfactants, Detergents ; Volume 53, Issue 4 , 2016 , Pages 324-331 ; 09323414 (ISSN) ; Bagheri Lotfabad, T ; Yaghmaei, S ; Sharif University of Technology
Carl Hanser Verlag
In the present study, an aqueous root-extract of Acanthophyllum laxiusculum (AREAL) was evaluated for phenanthrene removal from two samples of contaminated soil. AREAL showed a linear solubilization enhancement for phenanthrene with a weight solubilization ratio of 0.05. Batch soil washing experiments caused the removal of phenanthrene with efficiencies of 96.7% and 78% from soils with 0.78% and 2.73% organic carbon, respectively. Desorption kinetics of phenanthrene exhibited a twophase pattern, namely, a rapid release as the initial phase and a slower removal as a subsequent phase. A two-compartment exponential model could adequately represent the two phases of the kinetic pattern of...
Molecular design of carbazole-based dyes and the influence of Alkyl substituent on the performance of dye-sensitized solar cells, Article Molecular Crystals and Liquid Crystals ; Volume 629, Issue 1 , 2016 , Pages 29-43 ; 15421406 (ISSN) ; Zarandi, M ; Madram, A. R ; Bayat, Y ; Najafi Chermahini, A ; Ghahary, R ; Sharif University of Technology
Taylor and Francis Inc
Carbazole is an alternant polycyclic aromatic hydrocarbon consisting of three fused rings with a large, aromatic system, containing nitrogen atom showing extensive electron delocalization. In this work, carbazole applied as π-conjugated bridge to construct electron donor–π–electron acceptor (D–π–A) organic dyes, where barbutiric acid and thiazolidine-2,4-dione as electron acceptor. The effects of these three acceptors and length of alkyl on the performance of the DSSCs were investigated systematically along with their photophysical and photo electrochemical properties. These series of organic dyes include (B-CH, B-C B, DT-CB, DB-CB). Our investigation indicate among dyes containing butyl as...
Remediation of Polycyclic Aromatics Hydrocarbons- Containated Soils Using Plant-Derived Biousurfactants
Sharif University of Technology
Bagheri Lotfabad, Tayebe
Polyaromatic hydrocarbons are toxic compounds generally produced by combustion of explosives and petroleum materials. They cause soil and ground water contamination. PAHs are carcinogenic and lead to serious health problems for human and other living things; hence they should be removed from the environment. Soil washing technique has been one of methods applied for soil treatment during the years and surface active compounds like emulsifiers and surfactants have been introduced into washing process to improve the removal efficiency. On the other hand, synthetic surfactants made of chemicals and petroleum materials are not degradable and remain in the environment. To void this secondary...
A systematic study on the effect of noise and shift on multivariate figures of merit of second-order calibration algorithms, Article Analytica Chimica Acta ; Volume 952 , 2017 , Pages 18-31 ; 00032670 (ISSN) ; Parastar, H ; Sereshti, H ; Olivieri, A ; Tauler, R ; Sharif University of Technology
Elsevier B.V 2017
In the present study, multivariate analytical figures of merit (AFOM) for three well-known second-order calibration algorithms, parallel factor analysis (PARAFAC), PARAFAC2 and multivariate curve resolution-alternating least squares (MCR-ALS), were investigated in simulated hyphenated chromatographic systems including different artifacts (e.g., noise and peak shifts). Different two- and three-component systems with interferences were simulated. Resolved profiles from the target components were used to build calibration curves and to calculate the multivariate AFOMs, sensitivity (SEN), analytical sensitivity (γ), selectivity (SEL) and limit of detection (LOD). The obtained AFOMs for different...
Numerical study of inlet turbulators effect on the thermal characteristics of a jet propulsion-fueled combustor and its hazardous pollutants emission, Article Journal of Heat Transfer ; Volume 139, Issue 6 , 2017 ; 00221481 (ISSN) ; Ghafourizadeh, M ; Sharif University of Technology
American Society of Mechanical Engineers (ASME) 2017
This work numerically studies the effects of inlet air and fuel turbulators on the thermal behavior of a combustor burning the jet propulsion (JP) (kerosene-surrogate) fuel and its resulting pollutants emission including the nanoparticulate soot aerosols and aromatic compounds. To model the soot formation, the method employs a semi-empirical two-equation model, in which the transport equations for soot mass fraction and soot number density are solved considering soot nanoparticles evolutionary process. The soot nucleation is described using the phenyl route in which the soot is formed from the polycyclic aromatic hydrocarbons. Incorporating a detailed chemical mechanism described by 200...
Chemometric techniques coupled with NMR for matabolic profiling of lettuce exposed to polycyclic aromatic hydrocarbones, Article Analytical Biochemistry ; Volume 611 , 2020 ; Seraj, M ; Tajali, R ; Shavandi, S. R ; Parastar, H ; Sharif University of Technology
Academic Press Inc 2020
Treated waste water (TWW) quality varies due to the occurrence of polycyclic aromatic hydrocarbons (PAHs) up to low μg L−1. In this study, a non-targeted metabolomic analysis was performed on lettuce (Lactuca sativa L) exposed to 4 PAHs by irrigation. The plants were watered with different concentrations of contaminants (0–100 μg L−1) for 39 days under controlled conditions and then harvested, extracted and analyzed by nuclear magnetic resonance (NMR). Different chemometric tools based on principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) are proposed for the analysis of the complex data sets generated in the different exposure experiments....
Experimental Study and Optimization of Bioremediation of PAHs by Newly Isolated Thermophilic Filamentous Fungi in Slurry Bioreactor, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr ; Alemzadeh, Iran
Sustainable development requires the development and promotion of environmental management and a constant search for green technologies to treat a wide range of aquatic and terrestrial habitats contaminated by increasing anthropogenic activities. In this work we investigated the ability of four previously isolated fungi, BBRC 9057, BBRC 20020, BBRC 9058 and BBRC 9002, in degradation of polycyclic (PAHs) and the effect of UV irritation on fungi cell growth and degradation of PAHs. Also we studied the degradation of anthracene by thermophilic filamentous fungi in liquid and soil slurry bioreactor. Cell growth and anthracene degradation ability of BBRC 9057 increased 6.51 and 1.82 times rather...
M.Sc. Thesis Sharif University of Technology ; Molaei Dehkordi, Asghar ; Arabian, Daryoush
TPPB are characterized by a cell-containing aqueous phase, and an immiscible and biocompatible organic phase that partitions toxic/insoluble substrates to the cells base on their metabolic demand and the thermodynamic equilibrium of the system. Surface areas, Mass transfer coefficient, Hydrophobicity of polycyclic aromatic hydrocarbons (PAH) are considered as limitation in two phase partition bioreactors (TPPB). For solving of this challenge, in this project used solid particle for increment of mss transfer and surface area, and also solid particles can eliminate limitation of initial concentration of polycyclic aromatic hydrocarbon and ratio of aqueous/organic phases. Naphthalene is used as...
Novel one-pot synthesis of (4 or 5)-aryl-2-aryloyl-(1H)-imidazoles in water and tauto-isomerization study using NMR, Article Tetrahedron ; Volume 65, Issue 34 , 2009 , Pages 6882-6887 ; 00404020 (ISSN) ; Tondro, T ; Hashemi, M. M ; Sharif University of Technology
A simple and green route to synthesis of (4 or 5)-aryl-2-aryloyl-(1H)-imidazoles is described. Two isomers can tautomerize to each other by the heat absorption. The tauto-isomerization process was studied by NMR technique. Acidity and stability of products were studied using B3LYP method. © 2009 Elsevier Ltd. All rights reserved
High energy efficiency in syngas and hydrocarbon production from dissociation of CH4-CO2 mixture in a non-equilibrium pulsed plasma, Article Journal of Physics D: Applied Physics ; Volume 38, Issue 20 , 2005 , Pages 3804-3811 ; 00223727 (ISSN) ; Norouzi, S ; Mohammadi, T ; Sharif University of Technology
The efficient production of syngas from a CH4+CO2 mixture in an atmospheric pulsed glow discharge, sustained by corona pre-ionization, has been investigated. The products were mainly syngas (CO, H2) and hydrocarbons up to C4, with acetylene having the highest selectivity. The energy efficiency was within 15-40% for different experimental conditions, which demonstrates a comprehensive improvement relative to the achievements of other types of non-equilibrium plasma. These values are, however, comparable with the efficiencies obtained by gliding arc plasmas but this plasma operates at near room temperature. Furthermore, it has been shown that the energy efficiency is increased by decreasing...
Extension of linear isotherm regularity to long chain primary, secondary and tertiary alcohols, ketones and 1-carboxylic acids by group contribution method, Article Fluid Phase Equilibria ; Volume 234, Issue 1-2 , 2005 , Pages 11-21 ; 03783812 (ISSN) ; Kalantar, Z ; Sharif University of Technology
In this work, the group contribution approach has been used in combination with the linear isotherm regularity (LIR) equation of state to estimate pvT properties of primary, secondary and tertiary alcohols, ketones and 1-carboxylic acid. In addition, the isothermal compressibility and thermal expansion coefficient of these compounds have been predicted. We assume each of these organic compounds as a hypothetical mixture of methyl, methylene and a functional group, in which the interaction potential of each pair is assumed to be the average effective pair potential. Then, the LIR equation of state (EOS) has been extended to such a hypothetical mixture. Three basic compounds, namely propane,...
The selective aerobic oxidation of methylaromatics to benzaldehydes using a unique combination of two heterogeneous catalysts, Article Organic and Biomolecular Chemistry ; Volume 3, Issue 5 , 2005 , Pages 725-726 ; 14770520 (ISSN) ; Clark, J. H ; Karimi, B ; Macquarrie, D. J ; Sharif University of Technology
A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure. © The Royal Society of Chemistry 2005
Modified Nano Silica a Sorbent for Needle Trap Extraction of PAHs from Water Samples Followed by Gas Chromatography/Mass Spectrometric Determination, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib
In this study, a newly designed needle trap device (NTE) containing modified nanosilica as sorbent is used for sampling and preconcentration of some polycyclic aromatic hydrocarbons (PAHs) from headspace of aqueous solutions. An inexpensive modifier, cis-9-octadecenoic acid (oleic acid), which contains a long chain, was used to modify the surface of the nano-scaled silica particles. The hydrophobic interaction between oleic acid and aromatic compounds was the preliminary evidence for extraction of these compounds. After adsorption of selected compounds, thermal desorption was, subsequently, employed to transfer the extracted analytes into a GC–FID. Extraction time and temperature, flow rate...
M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib
Commercial solid phase microextraction fibers posses a few drawbacks such as relatively low recommended operating temperature, instability and swelling in organic solvents, breakage of the fiber, stripping of coatings, and bending of the needle. Some of these problems have been obviated by covalent bonding of the polymer phase to the fused-silica substrate by sol-gel technology, but the easy breakage of the fiber remains a problem. In this study a new technique for preparation of unbreakable, thin and very porous fiber coatings for solid phase microextraction was proposed. In this technique firstly an intermediate film consisting ...
Application of Gold Nanoparticles for Simultaneous Determination of Polycyclic Aromatic Hydrocarbons in Water Samples with the Aid of Multivariate Chemometric Methods, M.Sc. Thesis Sharif University of Technology ; Parastar Shahri, Hadi ; Hormozi Nezhad, Mohammad Reza
In this study, a multivariate-based strategy was developed for simultaneous determination of thirteen carcinogenic polycyclic aromatic hydrocarbons (PAHs) in water samples using gold nanoparticles (AuNPs) as solid-phase extraction (SPE) sorbent combined with gas chromatography-flame ionization detector (GC-FID). The extraction technique is based on the strong affinity between citrate capped AuNPs and PAHs. Furthermore, characterization of AuNPs was performed by UV-Vis and TEM techniques. A rotatable central composite design (CCD) combined with multiple linear regression (MLR) was used for designing the extraction procedure and developing models using the GC peak areas of 13 PAHs. Also,...
Development of a Solid-Phase Microextraction Method Based on Electrospun Polyetherimide Nanofibers for Determination of Polycyclic Aromatic Hydrocarbons in Aqueous Samples, M.Sc. Thesis Sharif University of Technology ; Bagheri, Habib
Attentions to nano materials due to their vast applications in different branches of science and technology have been remarkably increased in recent years. Nanofibers are an important class of nano materials which could be used as novel sorbents because of their high surface to volume ratio as a result of long lengths and nano-to-micro-scale diameters. Electrospinning is a broadly used technology which utilizes high electrostatic forces for producing nanofibers. In this study a novel high temperature resistant solid phase microextraction (SPME) fiber was prepared besed on Polyetherimide (PEI) by this method. The porosity of the PEI fiber was investigated by scanning electron microscopy...