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Preparation of poly(vinyl chloride) (PVC) ultrafiltration membranes from PVC/additive/solvent and application of UF membranes as substrate for fabrication of reverse osmosis membranes
, Article Journal of Applied Polymer Science ; Volume 135, Issue 21 , 2018 ; 00218995 (ISSN) ; Asadollahi, M ; Musavi, A ; Bastani, D ; Sharif University of Technology
John Wiley and Sons Inc
2018
Abstract
Ultrafiltration (UF) membranes were prepared from poly(vinyl chloride) (PVC) as main polymer, poly(vinyl pyrrolidone) (PVP) as additive, and 1-methyl-2-pyrrolidone (NMP) as solvent using Design Expert software for designing the experiments. The membranes were characterized by SEM, contact angle measurement, and atomic force microscopy. The performance of UF membranes was evaluated by pure water flux (PWF) and blue indigo dye particle rejection. In addition, the molecular weight cutoff of UF membranes was determined by poly(ethylene glycol) (PEG) rejection. The UF membranes were used as substrates for fabrication of polyamide thin film composite (TFC) reverse osmosis (RO) membranes. The...
Magnetic/pH-sensitive κ-carrageenan/sodium alginate hydrogel nanocomposite beads: Preparation, swelling behavior, and drug delivery
, Article Journal of Biomaterials Science, Polymer Edition ; Vol. 25, issue. 17 , 2014 , p. 1891-1906 ; Rahmani, Z ; Karami, S ; Pourjavadi, A ; Sharif University of Technology
Abstract
This work describes the preparation of magnetic and pH-sensitive beads based on κ-carrageenan and sodium alginate for use as drug-targeting carriers. Physical cross-linking using K+/Ca2+ ions was applied to obtain ionic cross-linked magnetic hydrogel beads. The produced magnetite beads were thoroughly characterized by TEM, SEM/EDS, XRD, FTIR, and VSM techniques. While the water absorbency (WA) of magnetic beads was enhanced by increasing the weight ratio of κ-carrageenan, introducing magnetic nanoparticles caused a decrease in WA capacity from 15.4 to 6.3 g/g. Investigation on the swelling of the hydrogel beads in NaCl, KCl, and CaCl2 solutions revealed the disintegration of beads depending...
Pre-deposited alkali (Li, Na, K) chlorides layer for effective doping of CuInSSe thin films as absorber layer in solar cells
, Article Solar Energy ; Volume 231 , 2022 , Pages 694-704 ; 0038092X (ISSN) ; Bagher Ghorashi, S. M ; Tajabadi, F ; Taghavinia, N ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
We introduce an effective method for copper indium sulfide selenide (CISSe) doping with different alkali metals (Li, Na and K) based on a pre-deposited alkali chloride layer. A simple and fast spray method is used for pre-deposition of alkali chloride layer (LiCl, NaCl, KCl) on substrate surface before spray pyrolysis deposition of copper indium disulfide CuInS2 (CIS) films followed by selenization. The different properties of alkali-doped CISSe films by the alkali chloride pre-deposition (ACPD) method were compared to the post-deposition treatment (PDT) method. Based on FESEM images, a highly compact film with large grains can be obtained for CISSe films doped with K(∼0.72 μm) and Na (∼0.56...
Investigation on the Solfate and Chloride ion Concentration on Carbon Nanotubes Frmation Via Arc Discharge in Aqueous Solution
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Khomamizade, Farzad (Supervisor)
Abstract
In this work, carbon nanotubes (CNTs) were synthesized via arc discharge in an aqueous solution. The role of iron catalyst in CNTs formation was investigated utilizing arc discharge in iron salts solution (Fe2(SO4)3 and FeCl3). Thermogarvimetric (TG) analysis showed the presence of multi-layered structures including multi-walled carbon nanotubes (MWCNTs) and multi-shelled graphite particles when processing was performed in DI-water. In the presence of iron ions, single-walled carbon nanotubes (SWCNTs) and double-walled carbon nanotubes (DWCNTs) were formed. The effect of iron ions (Fe3+) concentration on CNTs yield was investigated by Raman spectroscopy. The highest yield was obtained when...
Design and Fabrication of Optimumhalide Copper Vapour Lasers
,
M.Sc. Thesis
Sharif University of Technology
;
Sadighi Bonabi, Rasoul
(Supervisor)
Fluoride Removal from Radioactive Wastes of Isfahan's UCF Plant by Using Chemical Precipitation Method
, M.Sc. Thesis Sharif University of Technology ; Samadfam, Mohammad (Supervisor) ; Yavari, Ramin (Supervisor) ; Davarkhah, Reza (Co-Advisor)Chloride Leaching of Titanium Ore from Reservoir in the North Area for Poduction of TiO2
, M.Sc. Thesis Sharif University of Technology ; Yoozbashizadeh, Hossein (Supervisor)
Abstract
Titanium dioxide is one of the most important first material in many industrial applications and for producing Titanium.Although it was discovered more than 200 years ago and has been commercially processed for 85 years, it is still being actively investigated. So far Iran imports TiO2. But some projects have been planned to produce pure TiO2 from Ilmenite and Titanomagnetite ore. In the present work production of highly purity TiO2 from Ilmenite ore by chloride leaching has been investigated. Chloride leaching has been accomplished by several stages of leaching in hydrochloric acid, reduction, crystallization, hydrolysis and finally calcination of the powder. According to the result...
Design and Fabrication of Nanovolt Ag/AgCl Bio-potential Sensor
, M.Sc. Thesis Sharif University of Technology ; Fardmanesh, Mehdi (Supervisor) ; Simchi, Abdolreza (Co-Advisor)
Abstract
Biopotential sensors are used in a wide range of biomedical applications. For example, measuring electric potentials on the surface of living tissues in electroencephalography (EEG), electromyography (EMG), and electrocardiography (ECG) systems in which the brain, muscle, and heart activities respectively are measured over time. Moreover, these electrodes are used in measuring the pH of different materials and also in receiving and recording the electric field changes of the environment. The major purpose of biopotential electrodes is to act as a transducer between the ionic transport of the tissue and the electron flow in the electrode. Such a transduction takes place due to an oxidation or...
Dye Removal from Textile Effluent Using Membrane Process
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Textile industry is one of the biggest consumers of water in the world. Effluents of textile industry ordinarily have huge rate of dye compounds which are toxic and persistent in environment. In case which they did not treat and discharged in the environment, they can create cancer, poisoning and etc. Finding efficient, economic and fast method for treating of these effluents is an important factor on the management. Combination of ultrafiltration membrane and reverse osmosis processes, has taken into consideration as an efficient and fast method of treatment of textile effluents in recent years. One of the fundamental problems of this process is the high costs of operation and chemical...
Design and Fabrication of Electrical Field Sensor for Biological and Corrosion Currents Application
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Fardmanesh, Mehdi (Supervisor)
Abstract
Electric field sensors are one of the common types of sensors that are widely used today to record changes in the electric field in underwater environments, also record pH changes in different materials. This type of sensor is inspired by the shark mucous membrane. In this study, silver / silver chloride silver (Ag / AgCl) was used for three methods of silver filtration directly in electrolyte containing chloride ion, Electrophoretic electrode method and electrode making method using silver oxide adhesive. Part of the electrodes manufacturing method involves converting part of silver into silver chloride. The made electrode has a length of 7 cm and a diameter of 0.5 mm, with its core made of...
Continuous Synthesis of Silver Chloride Nanoparticles Using a Spinning Disk Reactor
, M.Sc. Thesis Sharif University of Technology ; Molaei Dehkordi, Asghar (Supervisor)
Abstract
Silver chloride nanoparticles (AgCl NPs) have been widely used in various areas such as medicine industry, photographic materials, catalytic materials, pigments, and photochromic materials. Therefore, various studies were conducted for their synthesizes. In the present work, precipitation or reactive crystallization method was used for the synthesis of AgCl NPs. In this regard, silver nitrate and sodium chloride as reactants and gelatin as a surfactant were used in a continuous spinning disk reactor (SDR) at the ambient temperature and pressure. The influences of various parameters such as initial supersaturation , free ion ratio, dilution with water , disk diameter , disk rotation speed,...
Preparing an Appropriate UF Membrane from PVC to Use it as Substrate in Sea Water Desalination RO Membranes
, M.Sc. Thesis Sharif University of Technology ; Bastani, Daruoosh (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
In this study the main goal is preparing an appropriate UltraFiltration membrane from PolyVinyl Chloride for using as substrate in producing efficient Reverse Osmosis membranes to use in sea water desalination. each membrane should have some specifications to use it as reverse osmosis membrane’s substrate. One of the most important specifications is the appropriate pore sizes. To investigate this subject pure water flux and PolyEthylene glycol rejection of prepared membranes is tested. After investigation of this parameters and proving them, RO membranes are prepared using this membranes.
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Salt rejection of Brackish water (2000ppm) and sea water (Persian gulf,32000ppm) are measured in...
Upgrading "Qaed Basir"Petrochemical Wastewater Treatment Plant
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Shayegan Salek, Jalaledin (Supervisor)
Abstract
Golpayegan Qaed Basir Petrochemical Company is one of the lucrative and entrepreneurial companies in Iran. Every day in this complex, a large amount of wastewater is being generated and transferred to the evaporative lag after the primary and secondary purification outside the complex and it is not restored. Considering the growing importance of surface and underground water resources, reuse of wastewater is a valuable production. In this research, the optimization of the sewage treatment system of the complex was evaluated by replacing the chemicals in the primary purification unit and also by using chloride-ferric and trickling filter for tertiary purification(treating) of the...
Enhancement of Alkaline Protease Production Using Process Factors
, M.Sc. Thesis Sharif University of Technology ; Roostaazad, Reza (Supervisor)
Abstract
In this research, we have studied optimization of culture medium and process factors for high alkaline protease production from Bacillus subtilis ATCC 6633 for detergent usage. Five parameter soy bean meal, initial pH, agitation rate, MgSO4, CaCl2 were selected for more studies. At first, one-factor-at-a-time method was applied to investigate effect of each factor separately. Then, optimum condition for maximum protease production was achieved using Minitab software Box-benhnken procedure. According to results, high protease production was seen in soy bean meal, 35 (g/L); MgSO4, 1 (g/L); CaCl2 , 1.5 (g/L); initial pH, 7; agitation rate, 150; inoculum ratio, 12% (v/v). The activity of the...
Electrodeposition and Characterization of Zn-Ni-Mn Coatings
, M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad (Supervisor)
Abstract
In this study, the electrochemical precipitation of three-component zinc-nickel-manganese coating on st37 steel substrate from chloride bath was investigated. Cyclic voltammetry results showed that the presence of ammonium thiocyanate complexer had a positive effect on the stability of precipitated manganese. Also, in order to evaluate the optimal coating conditions, the precipitation process at voltages of -1.4, -1.5 and VSCE -6.6, concentration of zinc 0.3 M, concentration of nickel 0.15 M and concentrations of manganese 0.15, 0.3 And 0.45 M and temperatures of 25, 40 and 55 .C. The results of X-ray energy diffraction spectroscopy, atomic absorption spectroscopy and X-ray diffraction of...
Investigation of the Effect of Chlorine ion Concentration on Corrosion of Steel Reinforcement in Concrete
, M.Sc. Thesis Sharif University of Technology ; Afshar, Abdollah (Supervisor)
Abstract
Today, in our beloved country of Iran and other parts of the world, reinforced concrete structures are used in large industrial projects, in some cases we see their very early failure even before the time of operation. This issue in the southern coasts of the country due to special weather conditions (humidity and high temperature) and the existence of the offensive ions such as chlorine and sulfate in seawater are more important and we always face with severe corrosion of reinforcement and reduced service life of concrete structures in these areas. Despite this, little research has been done on the reliability of concrete facilities in the vicinity of the Caspian Sea in the north of the...
Synthesis and Study of the Interaction of Aza-Crwon Macrocyclic Ligands with Carboxylate Side Arms with Cd Salts
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In the present study, the coordination chemistry of an amino acid azacrown macrocycle ligand bearing one carboxylic acid arm (MA1) was investigated by employing NMR spectroscopy, crystallography and computational chemistry. MA1 was synthetized by the reaction of chloroacetic acid with the parent azacrown macrocycle and its purity was confirmed with 13C and 1H NMR for the first time. A new MA1 homologue, MA3 was also successfully prepared and characterized with NMR, mass spectrometry, and elemental analysis. NMR studies showed that MA1 binds to cadmium via the carboxylate arm in solution. Crystallographic studies showed that MA1 formed a one-dimensional polymer with cadmium, wherein the...
Facile synthesis of thiochromeno[2,3-b]indol-11(6H)-ones and pyrido[3′,2′:5,6]thiopyrano[2,3-b]indol-5(10H)-ones
, Article Tetrahedron Letters ; Volume 54, Issue 37 , 2013 , Pages 5018-5021 ; 00404039 (ISSN) ; Moghaddam, F. M ; Semeniuchenko, V ; Villinger, A ; Langer, P ; Iaroshenko, V. O ; Sharif University of Technology
2013
Abstract
Indole-2(3H)thiones were cyclized under the action of 2-fluorobenzoyl chlorides to give thiochromeno[2,3-b]indol-11(6H)-ones or under the action of 2-chloronicotinoyl chlorides to give pyrido[3′,2′:5,6]thiopyrano[2, 3-b]indol-5(10H)-ones. The reaction of cyclization proceeds regioselectively in DMF and does not require transition metals for completion. Obtained heterocycles are isosteric analogues of various tetracyclic indole derived alkaloids
Partitioning of alkaline protease from Bacillus licheniformis (ATCC 21424) using PEG-K2HPO4 aqueous two-phase system
, Article Fluid Phase Equilibria ; Volume 337 , January , 2013 , Pages 1-5 ; 03783812 (ISSN) ; Pazuki, G. R ; Vossoughi, M ; Mirkhani, S. A ; Seifkordi, A. A ; Sharif University of Technology
2013
Abstract
An aqueous two-phase system (ATPS) containing polyethylene glycol (PEG) and potassium phosphate (K2HPO4) was used for partitioning and partial purification of alkaline protease produced by Bacillus licheniformis ATCC 21424. The effect of PEG molar mass, pH and concentration of NaCl salt addition on partition coefficient, yield and purification factor (PF) for ATPS were studied. The highest partition coefficient (5.3) was achieved in an ATPS of 25% (w/w) PEG 10,000 (g/mol) and 10% (w/w) NaCl at pH 9. Cation and anion exchange chromatography was employed for purification of alkaline protease from protein mixture and the yield and PF for enzyme fractions were obtained to make a comparison...
Characterization of ionic composition of TSP and PM10 during the Middle Eastern Dust (MED) storms in Ahvaz, Iran
, Article Environmental Monitoring and Assessment ; Volume 184, Issue 11 , November , 2012 , Pages 6683-6692 ; 01676369 (ISSN) ; Naddafi, K ; Jaafarzadeh Haghighifard, N ; Mesdaghinia, A ; Yunesian, M ; Nabizadeh, R ; Arhami, M ; Yarahmadi, M ; Sowlat, M. H ; Ghani, M ; Jonidi Jafari, A ; Alimohamadi, M ; Motevalian, S. A ; Soleimani, Z ; Sharif University of Technology
2012
Abstract
Because of the recent frequent observations of major dust storms in southwestern cities in Iran such as Ahvaz, and the importance of the ionic composition of particulate matters regarding their health effects, source apportionment, etc., the present work was conducted aiming at characterizing the ionic composition of total suspended particles (TSP) and particles on the order of ∼10 μm or less (PM10) during dust storms in Ahvaz in April-September 2010. TSP and PM10 samples were collected and their ionic compositions were determined using an ion chromatography. Mean concentrations of TSP and PM10 were 1,481.5 and 1,072.9 μg/m 3, respectively. Particle concentrations during the Middle Eastern...