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    Zwitterion-functionalized MIL-125-NH2-based thin-film nanocomposite forward osmosis membranes: towards improved performance for salt rejection and heavy metal removal

    , Article New Journal of Chemistry ; Volume 46, Issue 31 , 2022 , Pages 15205-15218 ; 11440546 (ISSN) Bayrami, A ; Bagherzadeh, M ; Navi, H ; Nikkhoo, M ; Amini, M ; Sharif University of Technology
    Royal Society of Chemistry  2022
    Abstract
    In the current study, thin-film nanocomposite membranes (TFN-Mx) based on a zwitterion-functionalized metal-organic framework (MOF) have been developed for the forward osmosis (FO) salt-water separation process. The active polyamide layer was formed through the interfacial polymerization of the m-phenylenediamine aqueous phase (with or without the presence of MIL-125-NH-CC-Cys) and the trimesoyl chloride organic phase. In comparison with the results from the surface of the unmodified membrane, a nanofiller-incorporated TFN-M0.10 membrane represents a smoother and more wettable surface that collaborates synergically to enhance the membrane antifouling ability. Among the examined membranes,... 

    On comparison of three multi-feed osmotic-mediation-based configurations for brine management: Techno-economic optimization and exergy analysis

    , Article Desalination ; Volume 525 , 2022 ; 00119164 (ISSN) Beni, A. N ; Ghofrani, I ; Moosavi, A ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    This study aims at analyzing the performance of three units known as low salt rejection reverse osmosis (LSRRO), split-feed counterflow reverse osmosis (SF-CFRO), and split-brine counterflow reverse osmosis (SB-CFRO) and implementing them in a modified multi-stage multi-feed counter-current membrane with cascade recycle for dewatering hypersaline streams to the salinity appropriate for crystallizers' feed. Exergy and primitive pinch analysis showed that dewatering is limited in SF-CFRO as the permeate inlet dictates the maximum salinity difference at the pinch point as well as high frictional pressure loss in the permeate channel. SB-CFRO and LSRRO units can reach high salinities by... 

    Desiccation of a saline lake as a lock-in phenomenon: A socio-hydrological perspective

    , Article Science of the Total Environment ; Volume 811 , 2022 ; 00489697 (ISSN) Pouladi, P ; Nazemi, A. R ; Pouladi, M ; Nikraftar, Z ; Mohammadi, M ; Yousefi, P ; Yu, D. J ; Afshar, A ; Aubeneau, A ; Sivapalan, M ; Sharif University of Technology
    Elsevier B.V  2022
    Abstract
    Understanding of how anthropogenic droughts occur in socio-hydrological systems is critical in studying resilience of these systems. This is especially relevant when a “lock-in” toward watershed desiccation occurs as an emergent outcome of coupling among social dynamics and surface and underground water processes. How the various processes collectively fit together to reinforce such a lock-in and what may be a critical or ignored feedback worsening the state of the socio-hydrological systems remains poorly understood. Here we tackle this gap by focusing on the case of Lake Urmia in Iran, a saline lake that faces the same fate as that of Aral Sea due to over-extraction of water sources that... 

    Annual comparative performance and cost analysis of high temperature, sensible thermal energy storage systems integrated with a concentrated solar power plant

    , Article Solar Energy ; Volume 153 , 2017 , Pages 153-172 ; 0038092X (ISSN) Mostafavi Tehrani, S. S ; Taylor, R. A ; Nithyanandam, K ; Shafiei Ghazani, A ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    The present study conducts a comprehensive comparative techno-economic analysis of some near-term sensible thermal energy storage (TES) alternatives to the ‘standard’ two-tank molten salt system for concentrated solar power (CSP) plants. As such, we conducted detailed, relative annual transient simulations for single-medium thermocline (SMT), dual-media thermocline (DMT), and shell-and-tube (ST) systems. To be consistent with recent literature, the DMT and ST systems use concrete with a porosity of 0.2 (e.g. where concrete occupies 80% of the system) as their low cost filler material. The systems were integrated into a validated 19.9 MWe Gemasolar CSP model, which has a solar multiple of... 

    The lake urmia environmental disaster in Iran: a look at aerosol pollution

    , Article Science of the Total Environment ; Volume 633 , 2018 , Pages 42-49 ; 00489697 (ISSN) Hossein Mardi, A ; Khaghani, A ; MacDonald, A. B ; Nguyen, P ; Karimi, N ; Heidary, P ; Karimi, N ; Saemian, P ; Sehatkashani, S ; Tajrishy, M ; Sorooshian, A ; Sharif University of Technology
    Abstract
    Lake Urmia (LU) once was the second largest hypersaline lake in the world, covering up to 6000 km2, but has undergone catastrophic desiccation in recent years resulting in loss of 90% of its area and extensive coverage by playas and marshlands that represent a source of salt and dust. This study examines daily Aerosol Optical Depth (AOD) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) between 2001 and 2015 over northwestern Iran, which encompasses LU. Intriguingly, salt emissions from the LU surface associated with ongoing desiccation do not drive the study region's AOD profile, whereas pollution transported from other regions and emissions around LU are more important.... 

    Synthesis of Dithiocarbamate Derivatives and Their Applications to Prepare Heterocyclic Compounds

    , M.Sc. Thesis Sharif University of Technology Alaei Tazehgheshlagh, Mohammad Ali (Author) ; Saeedi, Mohammad Reza (Supervisor)
    Abstract
    Sulfur containing compounds are known as the most applicable group of organic compounds. Due to their medicinal and biological applications, dithiocarbamates are the most considerable among the many sulfur containing compounds. There are many procedures reported to synthesize these compounds as synthetic intermediates instead of thiophosgen and isothiocyanates. The reaction of amine and carbon disulfide is reported as the best and least hazardous way to synthesize this functional group. In this project heterocyclic compounds such as thiazoles, thiazolidine-2-thione, and 2-(alkylthio)thiazol-4(5H)-one derivatives were synthesized from the reaction of prepared dithiocarbamates with in situ... 

    , M.Sc. Thesis Sharif University of Technology Khodabakhshi, Mohammad Reza (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    1,3-Dipolar cycloaddition reactions constitute one of the most fundamental reactions for construction of five-membered heterocyclic compounds Spiro and dispirooxindoles have become important synthetic targets as these structural frameworks form the core units of many naturally occurring molecules that possess abundant biological activities .In this report we used (E)-Aryl ideneindolinones as unusual dipolarophiles for synthesis of dispirooxindoles. In follow different bifunctional nucleophiles for example 1,3-dicarbonyl, phenol, thioindole can be used in synthesis of benzoxazocines We have reported a new and efficient synthesis of benzoxazocines via unique tandem 1,3-dinucleophilic addition... 

    Geomechanical Analysis of Wellbore Instability in Kupal Oil Field

    , M.Sc. Thesis Sharif University of Technology Mellat, Soheil (Author) ; Khoei, Amir Reza (Co-Advisor) ; Erfan Nia, Ali (Co-Advisor) ; Shad, Saeed (Supervisor)
    Abstract
    The wellbore instability is one of the challenging problems in the oil industry, which entails huge costs for the industry every year. This phenomenon not only causes numerous problems in drilling and completion of wells, but also reduces production and loss of wells. In recent years, this problem has become much more serious in the Kupal oilfield. As a result, a large number of wells drilled in the field shortly after completion face with the problem of instability, integrity and casing collapse. According to the studies, one of the main causes of such a problem is the Gachsaran high pressure formation. Despite the complexity and importance of this issue, there is not a comprehensive study... 

    Experimental Study and Prediction of Vancomycin Partitioningin Surfactant-Salt Aqueous Two-Phase Systems

    , M.Sc. Thesis Sharif University of Technology Shirvani, Sara (Author) ; Vosughi, Manouchehr (Supervisor) ; Rashtchian, Davood (Supervisor) ; Pazuki, Gholamreza (Supervisor)
    Abstract
    In the past years, upstream processes have been receiving a considerable R&D investment and commercial attention. The downstream processes have, however, been overlooked causing a production bottleneck that is shifting the costs of production from up to downstream. The need to develop more efficient and cost-effective separation and purification processes is, thus, crucial in order to improve process efficiency and economics keeping the required high standards of quality for market approval. In this research, promising aqueous two-phase systems (ATPS) containing Tween 20 as a quite biocompatible non-ionic surfactant and different salts (K3Citrate and NaH2PO4) were prepared and their... 

    Mahaarloo Salt Lake Restoration Policy Study Using DPSIR Approach

    , M.Sc. Thesis Sharif University of Technology Shoorrahmati, Abdullah (Author) ; Abrishamchi, Ahmad (Supervisor)
    Abstract
    Lakes, marshes, and wetlands shrinkage and drying up due to natural and human driving forces is today one of the most important concerns in the world. Mahaarloo Salt Lake in southern part of Iran is (18 km far from south eastern of Shiraz ) drying-up and is faced with ecologic and environmental degradation. It recharges from western north by upstream basin of Shiraz and 3 rivers named Khoshk, Chenaarrahdaar, Soltaanabad and also from eastern south by Nazarabad river located in Sarvestan basin (Regional water org. of Fars 1382). In recent years, the shrinkage of Mahaarloo has been exacerbated by mismanagement of water resources, inappropriate land use, ignoring allocation of environmental... 

    Integrated Geomechanical Modeling of Casing Failure; From Lab to Simulation

    , Ph.D. Dissertation Sharif University of Technology Taheri, Reza (Author) ; Pak, Ali (Supervisor) ; Shad, Saeed (Co-Supervisor)
    Abstract
    Casing failure is one of the mainly problems of hydrocarbon fields that may cause wells out of service and impose heavy costs on oil companies. There exist many theories that may cause casing failure including: the plastic behavior of surrounding formations, the effects of reservoir depletion, over-pressured formations, weak cementing operations, fault activation, and local stresses applied on casing. In salt-rich formations, creep behavior can be the main cause of casing failure, too.The purpose of this study is to evaluate the causes affecting casing failure via experimental studies and numerical simulation with the focus on the conditions governing south-west Iranian oil fields, where the... 

    Effects of Microstructure and Salinity Concentration on Hydraulic Conductivity of Silty Clay Soils

    , M.Sc. Thesis Sharif University of Technology Khodadadi, Saeed (Author) ; Sadeghi, Hamed (Supervisor)
    Abstract
    Various contaminants and their leachate, when they penetrate into the soil, cause changes in soil microstructure, this change in microstructure leads to changes in soil permeability and volume. In this study, first, the effects of soil microstructure change on the hydraulic conductivity of saturated soil were investigated using the change in initial saturation degree during compaction for compacted samples and the change in sample construction in reconstituted samples. Also, the simultaneous effect of changing the initial microstructure and salt solution on the hydraulic conductivity of saturated silty clay soils using a three-axial permeability device with the ability to measure volume... 

    Investigation of the Influence of Charge and External Field on Desalination by Carbon Nanostructures Using Molecular Dynamics Simulation

    , Ph.D. Dissertation Sharif University of Technology Mortazavi, Vahid Reza (Author) ; Moosavi, Ali (Supervisor) ; Nouri-Borujerdi, Ali (Co-Supervisor)
    Abstract
    Membrane filtration systems are one of the most widely used and effective methods for desalination of saline water in the seas and oceans and treatment of industrial and domestic effluents in order to provide the fresh water resources needed for human survival on the earth and also meet the needs of various industries. The low efficacy of the traditional technologies necessitates the introduction of novel desalination methods. For this purpose, carbon-based membranes have been proposed as high-performance membranes because of their high mechanical strength, ultrafast permeation, and controllable pore size. In this study, by conducting molecular dynamics simulations, the effects of electric... 

    Hybrid Aqueous/Nonaqueous Electrolyte for Ca-Ion Batteries

    , M.Sc. Thesis Sharif University of Technology Noorsina, Saba (Author) ; Sadrnezhaad, Khatiboleslam (Supervisor) ; Yoozbashizadeh, Hossein (Supervisor)
    Abstract
    Water-in-salt (WIS) electrolytes with a wide electrochemical stability window (ESW) have made great progress in the field of aqueous batteries and capacitors. However, the slow diffusion of metal ions, such as lithium or calcium, has limited the use of these devices. Meanwhile, adding an organic co-solvent can improve the penetration of metal ions in salt water electrolytes. This electrolyte category, which has also used organic solvent in addition to water, is called organic/aqueous hybrid electrolyte modification. Since the effect of organic solvent on the performance of aqueous electrolyte in calcium batteries has not been investigated so far, in this research the physical and chemical... 

    Molecular Dynamics Simulation of Hydrogen Diffusion into Brine: Implications for Underground Hydrogen Storage

    , M.Sc. Thesis Sharif University of Technology Kalati, Saba (Author) ; Ayatollahi, Shahaboddin (Supervisor) ; Mahani, Hassan (Supervisor) ; Pourkhiabani, Nahid (Co-Supervisor) ; Esmaeilbeig, Mohammad Amin (Co-Supervisor)
    Abstract
    The high consumption of worldwide fossil energy and its detrimental effects on the environment and climate have prompted a transition toward renewable energy sources. The availability of renewable energy sources depends on weather and seasonal changes; therefore, an imbalance between supply and demand would be unavoidable. Hydrogen storage as an energy carrier, can fulfill this energy mismatch. Storing hydrogen in underground formations, such as aquifers, has been the subject of extensive research recently. In these storage reservoirs, hydrogen contacts the resident brine which will be lost through the dissolution-diffusion mechanism. Therefore, successful design of these storages requires... 

    Fast restoration of natural images corrupted by high-density impulse noise

    , Article Eurasip Journal on Image and Video Processing ; Volume 2013 , 2013 ; 16875176 (ISSN) Hosseini, H ; Marvasti, F ; Sharif University of Technology
    2013
    Abstract
    In this paper, we suggest a general model for the fixed-valued impulse noise and propose a two-stage method for high density noise suppression while preserving the image details. In the first stage, we apply an iterative impulse detector, exploiting the image entropy, to identify the corrupted pixels and then employ an Adaptive Iterative Mean filter to restore them. The filter is adaptive in terms of the number of iterations, which is different for each noisy pixel, according to the Euclidean distance from the nearest uncorrupted pixel. Experimental results show that the proposed filter is fast and outperforms the best existing techniques in both objective and subjective performance measures... 

    Sparse signal processing using iterative method with adaptive thresholding (IMAT)

    , Article 2012 19th International Conference on Telecommunications, ICT 2012, 23 April 2012 through 25 April 2012, Jounieh ; 2012 ; 9781467307475 (ISBN) Marvasti, F ; Azghani, M ; Imani, P ; Pakrouh, P ; Heydari, S.J ; Golmohammadi, A ; Kazerouni, A ; Khalili, M. M ; Sharif University of Technology
    IEEE  2012
    Abstract
    Classical sampling theorem states that by using an anti-aliased low-pass filter at the Nyquist rate, one can transmit and retrieve the filtered signal. This approach, which has been used for decades in signal processing, is not good for high quality speech, image and video signals where the actual signals are not low-pass but rather sparse. The traditional sampling theorems do not work for sparse signals. Modern approach, developed by statisticians at Stanford (Donoho and Candes), give some lower bounds for the minimum sampling rate such that a sparse signal can be retrieved with high probability. However, their approach, using a sampling matrix called compressive matrix, has certain... 

    Cellulose-immobilized NHC-Cu(i) complex: An efficient and reusable catalyst for multicomponent synthesis of 1,2,3-triazoles

    , Article RSC Advances ; Volume 5, Issue 120 , Nov , 2015 , Pages 99498-99501 ; 20462069 (ISSN) Pourjavadi, A ; Habibi, Z ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    A novel cellulose supported copper NHC complex has been prepared by the reaction of cellulose supported imidazolium salt with copper(i) iodide. The catalyst is active in the synthesis of 1,2,3-triazoles via a one-pot reaction of alkyl/benzyl halides or tosylates and terminal alkynes, with sodium azide in water  

    Investigation of salts behavior at liquid–liquid interfaces

    , Article Springer Proceedings in Mathematics and Statistics, 26 August 2013 through 30 August 2013 ; Volume 117 , July , 2015 , Pages 265-270 ; 21941009 (ISSN) ; 9783319123066 (ISBN); 9783319123066 (ISBN) Khiabani, N. P ; Bahramian, A ; Soltani, M ; Pourafshary, P ; Sarikhani, K ; Chen, P ; Ejtehadi, M. R ; Makarov R. N ; Melnik R. V. N ; Kotsireas I. S ; Shodiev H ; Cojocaru M. G ; Cojocaru M. G ; Makarov R. N ; Melnik R. V. N ; Kotsireas I. S ; Shodiev H ; Sharif University of Technology
    Springer New York LLC  2015
    Abstract
    We have used molecular dynamics simulation to investigate hydrophilic– hydrophobic interfaces between calcium chloride (CaCl2) aqueous solutions and normal hexane. The results demonstrate the increasing impact of salt concentration on the liquid–liquid interfacial tension, hence, negative adsorption of CaCl2 according to Gibbs adsorption isotherm. Moreover, we calculated the density profiles of hexane, water, and the counter ions. The results reveal an electrical double layer near the interface and the less affinity of calcium cations toward the interface than that of chloride anions. Orientation of water molecules at the studied concentrations may result in developing a positively charged... 

    Experimental study and mathematical modeling of partitioning of β-amylase and amyloglucosidase in PEG-salt aqueous two-phase systems

    , Article Journal of Chemical and Engineering Data ; Volume 55, Issue 11 , 2010 , Pages 4968-4975 ; 00219568 (ISSN) Shahriari, S ; Vossoughi, M ; Taghikhani, V ; Safekordi, A. A ; Alemzadeh, I ; Sharif University of Technology
    2010
    Abstract
    In this study, the partitioning of β-amylase in aqueous two-phase systems (ATPS) containing polyethylene glycol (PEG) with a molar mass of 6000 and 10 000 and KH 2PO 4 at T = (301.65 and 304.65) K was experimentally studied. In addition, the partitioning of amyloglucosidase in ATPS containing polyethylene glycol with molar mass of 4000, 6000, and 10 000 in the presence of Na 2SO 4 at T = (301.65 and 305.65) K was investigated. The effects of molar mass of PEG, temperature, mass fractions of salt, and the length of the tie line on partition coefficients of the enzymes were also studied. The experimental results showed that while the partition coefficients of enzymes decrease with increasing...