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Graphene oxide for rapid determination of testosterone in the presence of cetyltrimethylammonium bromide in urine and blood plasma of athletes
, Article Materials Science and Engineering C ; Volume 61 , 2016 , Pages 246-250 ; 09284931 (ISSN) ; Akhavan, O ; Ghaderi, E ; Hashemi, E ; Mortazavi, S. S ; Farmany, A ; Sharif University of Technology
Abstract
Electro-reduction behavior of testosterone at reduced graphene oxide/glassy carbon electrode (rGO/GCE) was studied. Cationic surfactant cetyltrimethylammonium bromide (CTAB) enhanced the reduction peak of testosterone. In borate buffer (pH 5.4) CTAB-testosterone showed a reduction peak at - 1.1 V (versus, Ag/AgCl). The increment of peak current obtained by deducting the reduction peak current of the CTAB-testosterone was rectilinear with testosterone concentration in the range of 2.0 to 210.0 nM, with a detection limit of 0.1 nM. The sensor was used for quantification of testosterone in biological fluids and drug
Layered ruddlesden–popper perovskites with various thicknesses for stable solid-state solar cells
, Article Physics of the Solid State ; Volume 62, Issue 3 , 2020 , Pages 529-541 ; Abdizadeh, H ; Mirhosseini, M ; Taghavinia, N ; Sharif University of Technology
Pleiades Publishing
2020
Abstract
Abstract: The present research comes up with optimizing the layers thickness of a Ruddlesden–Popper perovskite with the general formula of (S0.97S0.03 ')2[Cs0.05(FA0.097MA0.03)0.95]n – 1Pbn(I0.97Br0.03)3n + 1 for efficient, stable solar cell applications. Such a triple-cation quasi-two-dimensional (2D) structure simultaneously contains two spacers, namely 5-ammonium valeric acid iodide (S) and tetra-n-octylammonium bromide (S'). Systematic studies showed that morphology, crystal structure, optical properties, photovoltaic performance, and internal resistances of this compound depended upon the value of the n integer. Field emission scanning electron microscopy set forth that the deposited...
Extended-gate field-effect transistor based sensor for detection of hyoscine n-butyl bromide in its pharmaceutical formulation
, Article Analytical and Bioanalytical Electrochemistry ; Volume 12, Issue 2 , 2020 , Pages 238-249 ; Mirzaie, S. I ; Fardmanesh, M ; Norouzi, P ; Sharif University of Technology
Center of Excellence in Electrochemistry, Univ. of Tehran
2020
Abstract
A novel recognition method for selective determination of the hyoscine N-Butyl bromide (HBB), an antispasmodic agent for smooth muscles, was devised using extended gate field-effect transistor (EG-FET) as transducing unit. For this purpose a PVC membrane, containing hyoscine n-butyl-tetraphenyl borate ion-pair as recognition component, was coated on Ag/AgCl wire, which was connected to the extended metal gate. In optimal conditions, the linear range for HBB was 10-8-10-5 molL−1 with limit of detection 1.7×10-9 molL-1. The proposed sensor was applied in real sample, it showed fast response with high accuracy, and therefore it could be used as HPLC detector in the pharmaceutical samples in...
The first report on the catalytic oxidation of urazoles to their corresponding triazolinediones via in situ catalytic generation of Br+ using periodic acid or oxone®/KBr system
, Article Journal of Molecular Catalysis A: Chemical ; Volume 270, Issue 1-2 , 2007 , Pages 219-224 ; 13811169 (ISSN) ; Bagherzadeh, M ; Mallakpour, S ; Chehardoli, G ; Ghorbani Choghamarani, A ; Koukabi, N ; Dehghanian, M ; Doroudgar, M ; Sharif University of Technology
2007
Abstract
A combination of periodic acid or oxone® and a catalytic amount of KBr in the presence of few drops of water, were used for the catalytic oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogeneous conditions with moderate to excellent yields. © 2007 Elsevier B.V. All rights reserved
Michael-addition-initiated chemoselective three-component reaction for the synthesis of 2-(3-oxo-1,3-diarylpropyl)malononitrile derivatives using cerium(iv) ammonium nitrate in phosphorus ionic liquid
, Article Polycyclic Aromatic Compounds ; 2021 ; 10406638 (ISSN) ; Batooie, N ; Mousavi, R ; Miraghaee, S ; Hosseinzadeh, N ; Mousavian, M ; Hoshyari, A ; Sajadimajd, S ; Mohammadi, B ; Hatami, R ; Sharif University of Technology
Taylor and Francis Ltd
2021
Abstract
The aim of this research is the study of hexyltriphenylphosphonium bromide (HTPB) ionic liquid as a bifunctional promoter (solvent and catalyst) in the presence of cerium(IV) ammonium nitrate as a single electron oxidant for the Michael reaction at room temperature and solvent-free conditions. A novel, one-pot and environmentally benign the process to achieve the chemoselective of 2-(3-oxo-1,3-diarylpropyl)malononitrile derivatives instead of 2-(1,3-diarylallylidene)malononitriles using a three-component reaction involving acetophenone derivatives, various aromatic aldehydes and malononitrile was developed. This protocol is simple and provides biologically interesting products in good...
Michael-Addition-Initiated chemoselective three-component reaction for the synthesis of 2-(3-Oxo-1,3-diarylpropyl)malononitrile derivatives using cerium(IV) ammonium nitrate in phosphorus ionic liquid
, Article Polycyclic Aromatic Compounds ; Volume 42, Issue 9 , 2022 , Pages 6328-6336 ; 10406638 (ISSN) ; Batooie, N ; Mousavi, S. R ; Miraghaee, S. S ; Hosseinzadeh, N ; Mousavian, S ; Hoshyari, A ; Sajadimajd, S ; Mohammadi, B ; Hatami, R ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
The aim of this research is the study of hexyltriphenylphosphonium bromide (HTPB) ionic liquid as a bifunctional promoter (solvent and catalyst) in the presence of cerium(IV) ammonium nitrate as a single electron oxidant for the Michael reaction at room temperature and solvent-free conditions. A novel, one-pot and environmentally benign the process to achieve the chemoselective of 2-(3-oxo-1,3-diarylpropyl)malononitrile derivatives instead of 2-(1,3-diarylallylidene)malononitriles using a three-component reaction involving acetophenone derivatives, various aromatic aldehydes and malononitrile was developed. This protocol is simple and provides biologically interesting products in good...
Design and Fabrication of Optimumhalide Copper Vapour Lasers
,
M.Sc. Thesis
Sharif University of Technology
;
Sadighi Bonabi, Rasoul
(Supervisor)
Design and Construction of Copper Bromide Laser
, M.Sc. Thesis Sharif University of Technology ; Saddighi Bonabi, Rasoul (Supervisor)
Abstract
In this work, design and construction of copper vapor and Cu Br laser is explained. By special design of copper electrodes the average power from Cu laser system was increased more than 20% in comparison to the same system with expensive electrodes made from molybdenum. However, the basic goal of this work was the construction of CuBr laser. Based on the home made fast trigger unit for Hydrogen thyratron, operation of the manufactured system was possible up to 25 kHz. By using special designed copper electrodes very uniform operation of CuBr plasma diluted in Ne gas was observed. By tuning of the laser parameters such as gas pressure, exciting voltage and pulse repetition rate, from 9 Cm3 of...
Toward chemical perfection of graphene-based gene carrier via ugi multicomponent assembly process
, Article Biomacromolecules ; Volume 17, Issue 9 , 2016 , Pages 2963-2971 ; 15257797 (ISSN) ; Akhavan, O ; Hashemi, E ; Shamsara, M ; Sharif University of Technology
American Chemical Society
Abstract
The graphene-based materials with unique, versatile, and tunable properties have brought new opportunities for the leading edge of advanced nanobiotechnology. In this regard, the use of graphene in gene delivery applications is still at early stages. In this study, we successfully designed a new complex of carboxylated-graphene (G-COOH) with ethidium bromide (EtBr) and used it as a nanovector for efficient gene delivery into the AGS cells. G-COOH, with carboxyl functions on its surface, in the presence of EtBr, formaldehyde, and cyclohexylisocyanide were participated in Ugi four component reaction to fabricate a stable amphiphilic graphene-EtBr (AG-EtBr) composite. The coupling reaction was...
Preconcentration and determination of pantoprazole by solid-phase extraction coupled with spectrophotometry using iron oxide nanoparticles modified with cetyltrimethylammonium bromide
, Article Nano Biomedicine and Engineering ; Volume 7, Issue 3 , 2015 , Pages 102-110 ; 21505578 (ISSN) ; Naghian, E ; Sahebi, H ; Asgari, S ; Sharif University of Technology
Open Access House of Science and Technology
2015
Abstract
Solid phase extraction coupled with spectrophotometric detection was applied to trace amounts of Pantoprazole (PP) drug using Cetyltrimethylammonium bromide coated-iron oxide magnetite nanoparticles CTAB@Fe3O4 MNPs. After characterization of the prepared nano-adsorbents, experimental parameters affecting the extraction efficiency of the developed method were optimized. The results obtained showed that this proposed approach is applicable in concentrations ranging from 0.1 to 1.5 μg/ml (R2 = 0.9958) indicating that follows Beer's-Lambert law. The limit of detection and the limit of quantification calculated to be 0.014 and 0.04 μg/ml, respectively. The repeatability of the proposed method was...
The synergic effects of anionic and cationic chemical surfactants, and bacterial solution on wettability alteration of carbonate rock: an experimental investigation
, Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 513 , 2017 , Pages 422-429 ; 09277757 (ISSN) ; Lashkarbolooki, M ; Ayatollahi, S ; Hashemi, A ; Sharif University of Technology
Abstract
Changing the wettability of reservoir rock towards strongly water-wet state is effective way to enhance oil recovery from fractured carbonate reservoirs which are typically oil-wet. Regarding this fact, the injection of surfactant and the bacterial solution as EOR agents is proposed in the current work as a potential method to alter the wettability of rock surface reservoir. Nevertheless, there is a definite lack of experimental data regarding this method and the synergistic effect of both chemical and bacterial solutions on this process. In this study, the sole and combined effects of the bacterial solution using an Enterobacter cloacae strain as a biosurfactant-producer are compared with...
Comparison between two different hemichromes of hemoglobins (HbA and HbS) induced by n-dodecyl trimethylammonium bromide: Chemometric study
, Article Colloids and Surfaces B: Biointerfaces ; Volume 63, Issue 2 , 2008 , Pages 183-191 ; 09277765 (ISSN) ; Parastar, H ; Jalali Heravi, M ; Chamani, J ; Chilaka, F. C ; Moosavi Movahedi, A. A ; Sharif University of Technology
2008
Abstract
The interaction of n-dodecyl trimethylammonium bromide (DTAB) with oxyhemoglobin A and oxyhemoglobin S is investigated using UV-visible absorption spectra and chemometric resolution techniques. Oxyhemoglobins (A and S) induced to partial oxidized form (ferrihemoglobin) by DTAB and finally transform to fully oxidized hemichrome. Hemichrome mole fractions of HbS are more than HbA because of more hydrophobic interaction of DTAB-HbS in second set of binding site relative to DTAB-HbA. The visible spectra between 500 and 650 nm are used for identifying the present components in solution because each species of hemoglobin has a specific spectrum in this region. The number of components and mole...
Apatite-coated Ag/AgBr/TiO2 visible-light photocatalyst for destruction of bacteria
, Article Journal of the American Chemical Society ; Volume 129, Issue 31 , 2007 , Pages 9552-9553 ; 00027863 (ISSN) ; Rahimnejad, S ; Haghighi, S ; Gholami, M. R ; Sharif University of Technology
2007
Abstract
Apatite-coated Ag/AgBr/TiO2 was prepared by deposition of Ag as novel metal to generate electron-hole pairs by extending the excitation wavelength to the visible-light region, AgBr, and hydroxy apatite as photosensitive material and adsorption bioceramic, respectively. The energy dispersive X-ray spectrometry clearly showed the presence of Ti, Ag, Ca, and P elements on the surface of catalyst. The bactericidal experiments in dark media indicated that only the novel catalyst shows inhibiting growth of bacteria in this case. A transmission electron microscopy image illustrated that catalyst nanoparticles adhere to the outer membrane of the cell and act as an inhibitor to the nourishment of...
Energy and Economic Analysis of Micro CHP Systems in Buildings
, M.Sc. Thesis Sharif University of Technology ; Sattari, Sourena (Supervisor)
Abstract
In recent decades, due to economic, political and environmental issues, tend to use of the CHP systems (combined heating and power) have increased. CHP systems not only increase energy efficiency, but also decrease fuel consumption and emission levels of systems. The use of CHP technology in the industry has a long history, but the use of these systems in the commercial and residential sector, is considered, recently. As to the residential buildings, both electricity and thermal energy demands fluctuate seasonally and hourly, so it is necessary to take account of the plant’s annual operational strategies for the variations of load demands. In this paper, a nonlinear programming model is...
Activation of CX (=Cl, Br) bond in aryl halides toward the palladium-catalyzed Heck reaction using 2,6-bis(diphenylphosphino)pyridine
, Article Journal of Molecular Catalysis A: Chemical ; Volume 366 , January , 2013 , Pages 30-35 ; 13811169 (ISSN) ; Nadri, S ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
2013
Abstract
The 2,6-bis(diphenylphosphino)pyridine/palladium catalytic system successfully catalyzes the Heck coupling reaction of less reactive aryl chlorides as well as aryl bromides with styrene to give the corresponding olefins in reasonable yields. TBAB (tetrabutylammoniumbromide) as an additive was found to be essential for these reactions. The results of Heck reaction exhibited a high selectivity (>99/1) favoring the trans product
Enhanced hardness and corrosion resistance of Zn/SiO2 films by electrodeposition
,
Article
Journal of the Electrochemical Society
;
Volume 162, Issue 9
,
2015
,
Pages D480-D485
;
00134651 (ISSN)
; Salehi, F
; Razavizadeh, O
;
Sharif University of Technology
Electrochemical Society Inc
2015
Abstract
The electrodeposition of Zn-SiO2 nanocomposites has been investigated with different electrolytes: triethanolamine as a dispersing agent, and cetyl trimethylammonium bromide and dodecyl dimethylamine oxide as ionic (cationic) and non-ionic surfactants. Appropriate electrophoretic potentials for each solution were obtained using cyclic voltammetry. The results show that the most stable SiO2 nanoparticles with zeta potential range of 25 to 41 mV, along with highest SiO2 mobility of 0.4 to 0.7 m2/V.s were dispersed by triethanolamine in ethanol and the resulting coating adhesion improved up to 5.87 MPa in the standard pull off test, with the enhanced hardness of...
A heterogeneous strong basic nanocrystalline copper(II) oxide catalyst for efficient synthesis of 4-keto-4,5,6,7-tetrahydrobenzofurans
, Article Catalysis Communications ; Volume 10, Issue 10 , 2009 , Pages 1423-1426 ; 15667367 (ISSN) ; Sadjadi, S ; Hosseinpour, M ; Outokesh, M ; Hekmatshoar, R ; Sharif University of Technology
2009
Abstract
An efficient synthesis of tetrahydrobenzofurans is carried out in one pot through the reaction of 1,3-diketone and phenacyl bromides compound using a heterogeneous basic nano particles copper oxide catalyst. The protocol offers advantages in terms of higher yields, short reaction times, and mild reaction conditions, with reusability of the catalyst. © 2009 Elsevier B.V. All rights reserved
A smart-phone based ratiometric nanoprobe for label-free detection of methyl parathion
, Article Sensors and Actuators, B: Chemical ; Volume 322 , 2020 ; Hormozi Nezhad, M. R ; Sharif University of Technology
Elsevier B.V
2020
Abstract
The widespread use of pesticides in pest management has boosted the demands for developing highly sensitive probes for on-site monitoring. Herein we presented a sensitive enzyme-free ratiometric probe for determination of methyl parathion (MP), as an organophosphate pesticide using TGA-capped CdTe QDs and carbon dots (CDs). Unlike previous methods in which hydrolysis product of MP is instrumental in the response of the sensors, here, self-assembly of cetyltrimethylammonium bromide (CTAB) on the surface of non-modified yellow-emissive CdTe QDs facilitates the quenching of CTAB-QDs upon addition of MP while the fluorescence intensity of CDs remains constant. Using a smartphone, the ratiometric...
Template-directed hydrothermal synthesis of dandelion-like hydroxyapatite in the presence of cetyltrimethylammonium bromide and polyethylene glycol
, Article Ceramics International ; Volume 35, Issue 7 , 2009 , Pages 2563-2569 ; 02728842 (ISSN) ; Solati Hashjin, M ; Shafiei, S. S ; Salarian, R ; Nemati, Z. A ; Sharif University of Technology
2009
Abstract
A template-directed synthetic method, using surfactant cetyltrimethylammonium bromide (CTAB) as a template and co-surfactant polyethylene glycol (PEG600) as a co-template under hydrothermal conditions, has been applied to obtain dandelion-like HAp. The morphology, size, crystalline phase, chemical composition, physical characteristics, and thermal behavior of the product were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), Fourier ransform infrared spectroscopy (FTIR), induced coupled plasma spectroscopy (ICP), BET (Brunauer, Emmett, and Teller) method, and simultaneous thermal analysis (STA). SEM and TEM...
Polypyrrole nanowires network for convenient and highly efficient microextraction in packed syringe
, Article Analytical Methods ; Volume 3, Issue 11 , 2011 , Pages 2630-2636 ; 17599660 (ISSN) ; Ayazi, Z ; Sharif University of Technology
Abstract
A novel method based on microextraction in packed syringe (MEPS), as a sample preparation technique in combination with gas chromatography-mass spectrometry (GC-MS) was developed using a polypyrrole (PPy) nanowires network as the extracting medium. The PPy nanowires network was prepared using a soft template technique and its characterization was studied by scanning electron microscopy (SEM). The use of micelles in this methodology has an important role in the shape of the growing polymer. The pyrrole monomer was introduced into cetyltrimethylammonium bromide (CTAB) micelles and this has led to the formation of nanowires with diameters ranging from 30 to 60 nm. The bulk PPy prepared without...