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Cobalt salophen-modified carbon-paste electrode incorporating a cationic surfactant for simultaneous voltammetric detection of ascorbic acid and dopamine
, Article Sensors and Actuators, B: Chemical ; Volume 121, Issue 2 , 2007 , Pages 530-537 ; 09254005 (ISSN) ; Zare Mehrjardi, H. R ; Sharif University of Technology
2007
Abstract
A carbon-paste electrode (CPE) is modified by incorporating cobalt-5-nitrosalophen (CoNSal) and tetraoctylammonium bromide (TOAB). The mechanism of electrocatalytic oxidation of dopamine (DA) and ascorbic acid (AA) at the surface of the CoNSal-modified CPE containing various percents of TOAB is thoroughly investigated by cyclic and differential pulse voltammetry. In solutions of pH 5.0, in which all studies are performed, DA exists as the positively charged species whereas AA is mainly as the neutral form. Therefore, the favorable ionic interaction (electrostatic repulsion) between the cationic form of DA and the cationic surfactant (TOA+) caused increasing the overvoltage for DA and...
Electrodeposition of aluminum from molten AlCl3-NaCl-KCl mixture
, Article Journal of Applied Electrochemistry ; Volume 36, Issue 10 , 2006 , Pages 1169-1173 ; 0021891X (ISSN) ; Mahjani, M.G ; Gobal, F ; Danaee, I ; Sharif University of Technology
2006
Abstract
Electrochemical deposition of aluminum from basic and acidic molten NaCl-KCl-AlCl3 mixture on a graphite electrode at 140 °C was studied by voltammetry, chronopotentiometry and constant current deposition. The deposition of aluminum was found to proceed via a nucleation/growth mechanism in basic melt, while it was found to be diffusion controlled in acidic melt. The diffusion coefficient calculated for Al2Cl- 7 ions in acidic melt by voltammetry was in agreement with the deductions of voltammetry. The morphology of the aluminum deposits was examined using a metallographic microscope and by SEM. It was shown that, depending on the current density (c.d.) and AlCl3 concentration (acidic or...
Study and optimization of Amino Acid Extraction by emulsion Liquid Membrane
, Article CHISA 2006 - 17th International Congress of Chemical and Process Engineering, Prague, 27 August 2006 through 31 August 2006 ; 2006 ; 8086059456 (ISBN); 9788086059457 (ISBN) ; Vosoughi, M ; Alemzadeh, I ; Hexion Specialty Chemicals; Mitsubishi Chemical Corporation; CS Cabot; Zentiva; BorsodChem MCHZ ; Sharif University of Technology
2006
Abstract
A batch extraction of an essential amino acid, Phenylalanine, from an aqueous solution of different concentrations by an Emulsion Liquid Membrane (ELM) was developed using D2EHPA as a cationic carrier, Span 80 as the surfactant, paraffin and kerosene as the diluents, and HCl as the internal electrolyte. All effective parameters such as pH of initial aqueous external phase, electrolyte concentration in aqueous internal phase, carrier and surfactant concentration in emulsion, volume ratio of the organic to aqueous internal phase (Roi), volume ratio of the W/O emulsion to aqueous external phase (Rew) and time were examined and optimized using Taguchi method which was the first time of...
The effect of addition of Tiron as a surfactant on the microstructure of chemically deposited zinc oxide
, Article Materials Science and Engineering B: Solid-State Materials for Advanced Technology ; Volume 128, Issue 1-3 , 2006 , Pages 53-57 ; 09215107 (ISSN) ; Vaezi, M. R ; Sharif University of Technology
2006
Abstract
The effect of one of the surfactants such as Tiron, a compound based on the benzene molecule, on the morphology and chemical composition of zinc oxide deposits, produced from a zinc complex solution using two-stage chemical deposition (TSCD) technique, has been investigated. TSCD technique is a novel and simple chemical route for the deposition of ZnO film from aqueous solution. Zinc oxide films deposited on high purity alumina (HPA) as a substrate. The results show that the addition of Tiron changes the surface morphology and causes to form the fine-grained structure. With a dense and nodular-shape appearance, the film produced from the precursor of zinc complex-containing Tiron, is...
Azo dye removal via surfactant-assisted polyvinylidene fluoride membrane
, Article Environmental Health Engineering and Management ; Volume 8, Issue 1 , 2021 , Pages 25-32 ; 24233765 (ISSN) ; Mousavi, A ; Bagheri Lotfabad, T ; Heydarinasab, A ; Yaghmaei, S ; Sharif University of Technology
Kerman University of Medical Sciences
2021
Abstract
Background: Recently, concerns have been raised regarding the environmental and public health safety of azo dyes, the most widely used synthetic dyes. The membrane technique has been introduced as one of the efficient methods for dye removal treatments. Polyvinylidene fluoride (PVDF) membrane manipulated by surfactants was studied for removal of the azo dye, carmoisine. Methods: PVDF membrane was prepared via non-solvent-induced phase separation (NIPS) and used to remove the azo dye, carmoisine. Three nonionic surfactants including Tween 20, Tween 60, and Tween 80 were used individually as additives in casting solutions to improve PVDF membrane properties. Results: Fourier-transform infrared...
The effect of polymeric surfactant content on the mechanical properties of Al/GNP nanocomposites
, Article Materials Chemistry and Physics ; Volume 257 , 2021 ; 02540584 (ISSN) ; Abouchenari, A ; Pudine, M ; Sharifianjazi, F ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Graphene nanoplatelets (GNPs) are ideal reinforcements for improving the mechanical properties of aluminum-based matrices due to their outstanding properties. However, it essentially depends on their uniform dispersion in the matrix. In this study, the challenge of uniform dispersion of graphene was performed by functionalizing the non-covalent surface and sonication of GNPs applying non-ionic polymeric ethyl cellulose (EC) surfactant, in which a colloidal mixture was provided with Al powder and graphene, followed by sintering at 620 °C and consolidation. The density and mechanical properties of nanocomposite specimens were investigated and compared with a non-surfactant-assisted Al/GNP...
Experimental investigation and mathematical modeling of oil/water emulsion separation effectiveness containing alkali-surfactant-polymer
, Article Journal of Dispersion Science and Technology ; Volume 42, Issue 9 , 2021 , Pages 1286-1298 ; 01932691 (ISSN) ; Mellon, N ; Khan, J. A ; Al-Kayiem, H. H ; Sharif University of Technology
Bellwether Publishing, Ltd
2021
Abstract
Alkalis, surfactants and/or polymers are usually injected in the injector wells so that the injection fluids can sweep through the reservoir and mobilize/recover more oil. However, the formation of stable emulsion due to the residual chemicals in the recovered crude oil poses problems in the primary separation process. This study focuses on the effect of Alkali-Surfactant-Polymer injection on creaming and coalescence of crude oil and water emulsion produced in the primary gravity separator. In addition, a model is developed in this work to predict the separation effectiveness of oil and water emulsion containing ASP. In this work, the effect of ASP on the stability and the separation of...
Experimental investigation and mathematical modeling of oil/water emulsion separation effectiveness containing alkali-surfactant-polymer
, Article Journal of Dispersion Science and Technology ; Volume 42, Issue 9 , 2021 , Pages 1286-1298 ; 01932691 (ISSN) ; Mellon, N ; Khan, J. A ; Al-Kayiem, H. H ; Sharif University of Technology
Bellwether Publishing, Ltd
2021
Abstract
Alkalis, surfactants and/or polymers are usually injected in the injector wells so that the injection fluids can sweep through the reservoir and mobilize/recover more oil. However, the formation of stable emulsion due to the residual chemicals in the recovered crude oil poses problems in the primary separation process. This study focuses on the effect of Alkali-Surfactant-Polymer injection on creaming and coalescence of crude oil and water emulsion produced in the primary gravity separator. In addition, a model is developed in this work to predict the separation effectiveness of oil and water emulsion containing ASP. In this work, the effect of ASP on the stability and the separation of...
Highly efficient degradation of trichloroethylene in groundwater based on persulfate activation by polyvinylpyrrolidone functionalized Fe/Cu bimetallic nanoparticles
, Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 4 , Augus , 2021 ; 22133437 (ISSN) ; Shan, A ; Ali, M ; Abbas, Z ; Shahzad, T ; Hussain, S ; Mahmood, F ; Farooq, U ; Danish, M ; Lyu, S ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Polyvinylpyrrolidone coated nano zero valent iron-copper (PVP-nZVI-Cu) bimetallic nanoparticles were successfully synthesized for dechlorination of trichloroethylene (TCE) into non-toxic byproducts in the presence of persulfate oxidant. The average size of PVP-nZVI-Cu nanoparticles (3-25 nm) was smaller than PVP-nZVI (25-60 nm) and nZVI (50-90 nm) particles due to PVP role in the prevention of iron aggregation and agglomerations. The synthesized PVP-nZVI-Cu nanoparticles were used as an efficient persulfate (PS) activator to generate reactive oxygen species (ROSs) for the degradation of TCE. The complete removal of TCE (99.6%) was achieved in the presence of 0.4 g/L of PVP-nZVI-Cu...
Photo-induced CdS nanoparticles growth
, Article Physica E: Low-Dimensional Systems and Nanostructures ; Volume 30, Issue 1-2 , 2005 , Pages 114-119 ; 13869477 (ISSN) ; Azam Iraji Zad ; Mahdavi, S. M ; Reza-Esmaili, M ; Sharif University of Technology
2005
Abstract
A photochemical approach on the size control of CdS nanoparticles is presented. CdS nanoparticles were grown using the photo-induced reaction of sodium thiosulfate with Cadmium sulfate, in the absence of any surfactant. Particles of 5.5-11 nm were obtained by changing the illumination time. The dark growth of nanoparticles was negligible, however we found by optical scattering measurements that a ripening phenomenon occurs and the size of nanoparticles slightly increases with time. © 2005 Elsevier B.V. All rights reserved
A photochemical method for controlling the size of CdS nanoparticles
, Article Nanotechnology ; Volume 16, Issue 2 , 2005 , Pages 334-338 ; 09574484 (ISSN) ; Taghavinia, N ; Iraji Zad, A ; Mahdavi, S. M ; Sharif University of Technology
2005
Abstract
The optical and electrical properties of semiconductor nanoparticles are strongly dependent on their size. A flexible control of the size of the nanoparticles is of interest for tuning their properties for different applications. Here we use a coupled method to control the size of CdS nanoparticles. The method involves the photochemical growth of CdS nanoparticles together with the use of a capping agent as an inhibiting factor. CdS nanoparticles were formed through a photoinduced reaction of CdSO4 and Na2S2O3 in an aqueous solution. Mercaptoethanol (C2H6OS) was used as the capping agent, and we investigated the effect of illumination time, illumination intensity and the concentration of...
A machine learning framework for predicting entrapment efficiency in niosomal particles
, Article International Journal of Pharmaceutics ; Volume 627 , 2022 ; 03785173 (ISSN) ; Aftab, A ; Ghaemmaghami, S ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Niosomes are vesicles formed mostly by nonionic surfactant and cholesterol incorporation as an excipient. The drug entrapment efficiency of niosomal vesicles is particularly important and depends on many parameters. Changing the effective parameters to have maximum entrapment efficiency in the laboratory is time-consuming and costly. In this study, a machine learning framework was proposed to address these problems. In order to find the most critical parameter affecting the entrapment efficiency and its optimal value in a specific experiment, data were first extracted from articles of the last decade using keywords of niosome and thin-film hydration method. Then, deep neural network (DNN),...
Niosomal formulation for antibacterial applications
, Article Journal of Drug Targeting ; Volume 30, Issue 5 , 2022 , Pages 476-493 ; 1061186X (ISSN) ; Gharehchelou, B ; Haghighi Poodeh, S ; Jamshidifar, E ; Karimifard, S ; Farasati Far, B ; Akbarzadeh, I ; Seifalian, A ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Infection is a disease that is mainly caused by different Gram-negative and Gram-positive bacteria. Treatment of infections requires a considerable amount of antibiotics, which can cause serious damage to the patient's body. Delivering the antibiotic only to the site of infection can prevent these destructive effects, such as the destruction of the normal intestinal flora. The drug delivery system through carriers will take antibiotics into a part of the body involved in the disease. Niosome nanoparticles, which have been made from non-ionic surfactants, have been emerging as ideal drug/antibiotics delivery vehicles. Recently, niosome formulations have been targeted to reduce toxicity and...
Dissolution and remobilization of NAPL in surfactant-enhanced aquifer remediation from microscopic scale simulations
, Article Chemosphere ; Volume 289 , 2022 ; 00456535 (ISSN) ; Aminnaji, M ; Rezanezhad, F ; Ghazanfari, M. H ; Babaei, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this paper, the dissolution and mobilization of non-aqueous phase liquid (NAPL) blobs in the Surfactant-Enhanced Aquifer Remediation (SEAR) process were upscaled using dynamic pore network modeling (PNM) of three-dimensional and unstructured networks. We considered corner flow and micro-flow mechanisms including snap-off and piston-like movement for two-phase flow. Moreover, NAPL entrapment and remobilization were evaluated using force analysis to develop the capillary desaturation curve (CDC) and predict the onset of remobilization. The corner diffusion mechanism was also applied in the modeling of interphase mass transfer to represent NAPL dissolution as the dominant mass transfer...
Interplay between morphology and band gap energy in Fe-MIL-88A prepared via a high temperature surfactant-assisted solvothermal method
, Article Materials Chemistry and Physics ; Volume 277 , 2022 ; 02540584 (ISSN) ; Zebarjad, S. M ; Madaah Hosseini, H. R ; Khodaei, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Metal-Organic Frameworks (MOFs) are a new class of crystalline microporous solids with superior properties compared to their inorganic counterparts that offer a great variety of properties. Fe-MIL-88A is a biocompatible MOF with a flexible structure that can be synthesized in various morphologies via different chemical methods. The present study proposes two efficient methods, namely, microemulsion and surfactant-assisted solvothermal method, to prepare Fe-MIL-88A nanorods with narrow size distribution and well-defined morphology. The morphology, crystalline and chemical structure of the prepared samples were studied using FESEM images, XRD patterns and FTIR spectra, respectively, and their...