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    A fuzzy random minimum cost network flow programming problem [electronic resource]

    , Article Journal of Industrial and Systems Engineering (JISE)-Iranian Institute of Industrial Engineering ; Article 3, Volume 6, Issue 1, Spring 2012, Page 34-47 Nematian, J. (Javad) ; Eshghi, Kourosh ; Sharif University of Technology
    Abstract
    In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept  

    Special classes of mathematical programming models with fuzzy random variables [electronic resource]

    , Article Journal of Intelligent and Fuzzy Systems, Published In: IOS Press ; Volume 19, Number 2, 2008 Eshghi, K. (Kourosh) ; Nematian, Javad ; Sharif University of Technology
    Abstract
    In this paper, we will discuss two special classes of mathematical programming models with fuzzy random variables. In the first model, a linear programming problem with fuzzy decision variables and fuzzy random coefficients is introduced. Then an algorithm is developed to solve the model based on fuzzy optimization method and fuzzy ranking method. In the second model, a fuzzy random quadratic spanning tree problem is presented. Then the proposed problem is formulated and solved by using the scalar expected value of fuzzy random variables. Furthermore, illustrative numerical examples are also given to clarify the methods discussed in this paper  

    A special class of fuzzy integer programming model with all different constraints [electronic resource]

    , Article Scientia Iranica ; Vol. 16, No. 1, pp. 1-10, 2009 Eshghi, K. (Kourosh) ; Nematian, Javad ; Sharif University Of Technology
    Abstract
    In this paper, a fuzzy approach is applied to special classes of integer programming problems with all diierent constraints. In the rst model, a fuzzy integer programming model is developed to represent the all-diierent constraints in mathematical programming. In order to solve the proposed model, a new branching scheme for the Branch and Bound algorithm is also presented. In the second model, a special class of large-scale multi-objective fuzzy integer programming problems with all-diierent constraints is introduced. A solution method for the proposed model is also developed by using the decomposition technique, weighting method and Branch and Bound algorithm. An illustrative numerical... 

    Fuzzy random minimum cost network problem [electronic resource]

    , Article Journal of Industrial and Systems Engineering ; Vol. 6, No. 1, pp 34-47, 2012 Nematian, J. (Javad) ; Eshghi, Kourosh ; Sharif University of Technology
    Abstract
    In this paper, a fuzzy random minimum cost flow problem is presented. In this problem, cost parameters and decision variables are fuzzy random variables and fuzzy numbers respectively. The object of the problem is to find optimal flows of a capacitated network. Then, two algorithms are developed to solve the problem based on Er-expected value of fuzzy random variables and chance-constrained programming. Furthermore, the results of two algorithms will be compared. An illustrative example is also provided to clarify the concept  

    Fuzzy reliability optimization models for redundant systems [electronic resource]

    , Article International Journal of Industrial engineering ; July 2008, Vol. 4, No. 7, 1-9 Nematian, J. (Javad) ; Eshghi, Kourosh ; Eshraghniaye Jahromi, Abdolhamid ; Sharif University of Technology
    Abstract
    In this paper, a special class of redundancy optimization problem with fuzzy random variables is presented. In this model, fuzzy random lifetimes are considered as basic parameters and the Er-expected of system lifetime is used as a major type of system performance. Then a redundancy optimization problem is formulated as a binary integer programming model. Furthermore, illustrative numerical examples are also given to clarify the methods discussed in this paper  

    A resource constrained project scheduling problem with fuzzy random duration [electronic resource]

    , Article Journal of Uncertain Systems ; Vol.4, No.2, pp.123-132, 2010 Nematian, J. (Javad) ; Eshghi, Kourosh ; Eshragh Jahromi, Abdolhamid ; Sharif University of Technology
    Abstract
    In this paper, first a fuzzy random resource-constrained project scheduling problem is presented. The object of the problem is to find the optimal scheduling of project activities. In this model, duration of project activities is a fuzzy random variable. Then, the proposed model is formulated by using the expected value of fuzzy random variables as an IP model. An illustrative example is also provided to clarify the concept. © 2010 World Academic Press, UK. All rights reserved  

    Study of Supramolecular Chemistry of Fullerene (C60) with Azobenzene Tweezer Linking to Biaza-Crown Macrocycles Coordinated to Zinc Tetraphenylporphyrin

    , M.Sc. Thesis Sharif University of Technology (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In this project, in continuation of a PhD resreach undertaken in this research group in 2017, the synthesis and study of two new tweezer and linker molecule bearing azobenzene moiety were carried out, characterized by applying IR spectroscopy, ¹H and ¹³C {¹H} NMR, fluorescence spectroscopy, UV-visible spectroscopy, elemental analysis and X-ray crystallography. Firstly, interaction of T2 with meso-tetraphenylporphyrinato zinc(II) and aluminium tetraphenylporphyrinato were studied using the fluorescence spectroscopy. The formation constant of T2 in cis and trans isomer with ZnTPP was measured as 5.1(±0.4) ×108 and 2.0×108(±1074) dm6mol-2, respectively. The formation constant of T2 in with... 

    Waste Load Allocation in Rivers by Means of the Game Theory Case Study: Dez river

    , M.Sc. Thesis Sharif University of Technology Nematian, Maryam (Author) ; Abrishamchi, Ahmad (Supervisor) ; Arhami, Mohammad (Supervisor)
    Abstract
    Nowadays, by development of technology and population, rivers have been faced environmental issues. In one hand, due to the several factors that can affect rivers pollution, it is not easy to propose a comprehensive solution for the above mentioned issues, while, on the other hand, it is necessary to address and resolve some of these issues as soon as possible. Considering rives as a system, there are lots of economic, political and quite a few other factors which try to change the condition to their own interest. In order to find a solution that satisfies all the effective parameters up to a certain limit, a mathematical tool, called the Game theory method, is utilized. In this research, we... 

    Adsorption of eco-friendly carthamus tinctorius on steel surface in saline solution: a combination of electrochemical and theoretical studies

    , Article Colloids and Surfaces A: Physicochemical and Engineering Aspects ; Volume 601 , 20 September , 2020 Nematian, B ; Ramazani Saadat Abadi,A ; Mahdavian, M ; Bahlakeh, G ; Haddadi, S. A
    Elsevier B.V  2020
    Abstract
    In this study, the different parts of carthamus tinctorius plant, including petal (SPE), leaf (SLE), and shoot (SSE), have been extracted. Adsorption of the extracts on mild steel in 3.5 wt. % NaCl solution was evaluated employing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and electrochemical noise measurements (EN). The field-emission scanning electron microscopy (FE-SEM) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were employed to appraise the morphology of the samples surface subjected to the test solutions. According to the EIS results, the maximum adsorption efficiency belonged to the solution containing 1 g L−1 of... 

    Synthesis of C60 and Endohedral Fullerenes in New Multi-Channel Arc Reactor Equipped with Horizontal Graphite Electrodes

    , M.Sc. Thesis Sharif University of Technology Falahati, Reza (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    One of the most common methods of producing fullerenes is electric arc vaporization of graphite. Due to the low yield and purity of the nanoparticles in this method, the synthesis and isolation of the area research is important. In this work, the production was improved in a multi-channel arc reactor in which having horizontal graphite electrodes. The influence of various operational parameters such as pressure of inert gas, spark time, interval time between two sparks, voltage and current were completely optimized. Moreover, the prominent advantage of the new reactor was increasing the number of manufacturing units, at least from one to three, which the production of fullerene was... 

    Comparative Study on [60]Fullerene and Cu(II) Complexation with O2N3-Azacrowns

    , M.Sc. Thesis Sharif University of Technology Mahlooji, Niloofar (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    The purpose of this project is to synthesis of O2N3-azacrown ligands with 17 to 21 membered ring and investigation of their interaction with C60 according to increase ring size. These macrocyclic ligands can be used in C60 purification. In this project, change in macrocyclic cavity for finding the best macrocycle with appropriate cavity to C60 size has been considered. Firstly, five O2N3-azacrown ligands were synthesized and characterized by NMR spectroscopy and elemental analysis. Interaction of these ligands were considered by electronic spectroscopy applying Benesi-Hildebrand equation. According to the results, it was found that the best macrocycle for formation of stable complex with... 

    (Synthesis and Comparative Study on Complexation of OxNy-Azacrown Macrocyclic Ligands with [60] Fullerene and Cu(II

    , M.Sc. Thesis Sharif University of Technology Varmazyad, Mahboubeh (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In our previous work in this laboratory, macrocycle containingO_2 N_2 and O_2 N_3- donor set with various ring size were synthesized. The intraction of macrocyles with [60]fullerene were determined. In this research, we synthesized 22-membered aza-crown macrocycle ligand containing O_4 N_2- donor set and characterized by NMRspectroscopy. The intraction of macrocycle with [60]fullerene were also investigated by UV-Visible spectroscopy. The formation constant was determined applying Benesi--Hildebrand equation. The result has been showed that O_4 N_2 macrocyle had better complexation with [60]fullerene in comparision of O_2 N_3 and O_2 N_2 donor sets. Then, the interaction of O_4 N_2 with... 

    Synthesis and Electrochemical Study of Endohedral Fullerenes Prepared by Arc Vaporizing Method

    , M.Sc. Thesis Sharif University of Technology Hashemi, Ali (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    Fullerenes are molecular solid materials which are composed of 3D closed shell carbon-only structure. As soon as mass production of fullerenes was performed, the synthesis and characterization of endohedral fullerenes having at least one non-carbon element in the hollow fullerene cage, was started (in which about 30 atoms inserted in it so far). Furthermore, because of low efficiency and purity of these nano-particles, nowadays characterization of fullerenes is one of the most important research fields. In this project, we firstly optimized the fullerene production parameters in an arc discharge reactor to reach convenient efficiency. Then, the synthesis of endohedral fullerene by vaporizing... 

    Extractive Summarization based Cognitive Science of Human Mind for Narrative Text

    , M.Sc. Thesis Sharif University of Technology Sadeghi, Sareh (Author) ; Vazirnezhad, Bahram (Supervisor)
    Abstract
    In this project, a summarization system, which works for narrative text, based on cognitive science has been designed. Its results due to its different approach have been satisfactory. Since summarization has a direct relationship with comprehension of text. This system has been designed based on situational model, a famous theory related to comprehension of text.According to this theory, as human read a text, they extract five features for comprehension of text. The features are temporality, place, causality, protagonists, and intentionality. The make a frame based on these features. Event- Indexing model pays attention to all of these features, so it has been used for the summarization... 

    Synthesis of Azacrown Macrocyclic Ligand with Pendant Arms and Study of Their Complexation with [60] Fullerene and Cu(II) Cation

    , M.Sc. Thesis Sharif University of Technology Kazemi, Ameneh (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In this research, four N2O2–azacrown macrocyclic ligands with naphthalene pendant arms (L1-L4) were synthesized using direct synthesis. The products were characterized applying 1H and 13C {1H} NMR spectroscopy, IR and Mass spectrometry. Interaction of these ligands with [60]fullerene and Cu(II) were monitored respectively by fluorescent as well as UV-vis spectroscopy and applying Benesi-Hildebrand equation. These intercations were compared with N2O2 macrocyclic ligands in previous experiments in terms of their calculated association constants (Ka). According to our results, the presence of naphthalene pendant arm groups led to increase the interaction with [60]fullerene compared to the... 

    Synthesis of Azacrown Ethers N2O2 Ligands Substituted on the Ullerene and Investigation of Its Coordination Properties

    , M.Sc. Thesis Sharif University of Technology Khamseh, Leila (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    The goal of this project was study on coordination behavior of the 14-membered macrocyclic ligand of type N2O2 aza-crown while it is attached to fullerene C60 nano-particle. For this purpose, firstly the macrocyclic ligand (Fig 3-1, L1) was synthesized and then was reacted with C60 (Fig 3-1, L2) of which the product was characterized by elemental analysis. Since the product was insoluble in any solvents, further study on its coordination chemistry was impossible. In a second procedure, the macrocyclic ligand was reacted with benzylbromide. The reaction mixture gave two macrocyclic ligands with different number of benzylic pendant groups (Fig 3-1, L3-L4). The products were separated by column... 

    Study of NxOy Macrocycles Bearing Peripheral Functional Groups as Axial Ligands of Zinc Tetraphenylporphyrin

    , M.Sc. Thesis Sharif University of Technology Barkhordari, Kimia (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In this project, M2 macrocyclic ligand, bearing three pyridine side arms (3p) was synthesized and characterized by employing elemental analysis and 1H NMR, 13C NMR and IR methods. The interaction of 3p with zinc tetraphenylporphyrin was investigated, using fluorescence and UV-vis spectroscopy in solution phase. The observed quenching in the fluorescence spectrum alongside Q band shift in UV-vis spectrum indicate on the interaction of 3p with ZnTPP. The formation constant for these interactions in 1:1 ratio was calculated 10100 M-1, employing fluorescence method. The formation constant was calculated 630 M-1 for 1:2 ratio for 3p:ZnTPP. Having 1:2 ratio 3pZnTPP was also synthesized and... 

    Synthesis and Comparative Study on Complex Formation of Azo-bearing Nitrogen-Donor Macrocyclic Ligands with Fullerene C60 and Cu(II) Cation

    , Ph.D. Dissertation Sharif University of Technology Mahdavian, Mahsa (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In the present research, a series of bimacrocyclic tweezer anchored through azobenzene moiety were synthesized and characterized by applying IR spectroscopy, 1H and 13C{1H} NMR, fluorescence spectroscopy, UV-visible spectroscopy, mass spectrometry and elemental analysis and in some cases by X-ray crystallography. Firstly, UV-visible spectroscopy established that the irradiation of the tweezers with UV light promoted the trans to cis isomerization. On the other hand, thermal cis-trans isomerization behavior of the azobenzene moiety in tweezers was surveyed in which the cis isomers were formed of the heating at 50 oC for 5 minutes. Where the -OH group was replaced with 4-toluenesulfonyl... 

    Synthesis of Aza-Crown Macrocyclic Ligand Appended with Side Arms and Study of their Coordination and Supramolecular Chemistry with Cu2+ and C60

    , M.Sc. Thesis Sharif University of Technology Rezvanifar, Maryam (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In the present study, the coordination chemistry of an O4N4-tetrabenza-crown ether macrocyclic ligand L1 with M2+ (M= Cu, Cd, Hg, and Pb) was investigated by employing UV-visible, 1H-NMR spectroscopy in their solutions. According to the association constants calculated by 1H-NMR titrations, the complex formation stability for these closed shell cations was found in a series of Pb > Hg > Cd, leading to the larger cation, the better accommodation with L1. Moreover, the supramolecular interaction of L1 with fullerene C60 was also assessed by UV-visible spectroscopy. Meanwhile, the structure of [Cd(1)]2+ complex was determine by X-ray crystallographic method in their solid state. A square... 

    Synthesis and Study of Coordination and Supramolecular Chemistry of N2O4-Azacrown Macrocyclic Ligands with Cu(II) and [60]Fullerene

    , M.Sc. Thesis Sharif University of Technology Modhej, Maedeh (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    By considering previous experiments undertaken in our laboratory on OXNY (X=2,4 Y=2,3) azacrown complexes with [60]fullerene, it was found that factors such as the macroring size, type and number of the donor groups in these macrocyclic ligands had significant effects on their selectivity towards [60]fullerene complexation. In this research, 20 and 24-membered N2O4-azacrown macrocyclic ligands was synthesized and characterized applying 1H and 13C NMR spectroscopy, FT-IR as well as CHN elemental analysis. Interaction of these ligands with [60]fullerene and Cu(II) were monitored by UV-vis spectroscopy and applying Benesi-Hildebrand equation. The association constants (Ka) values related to the...