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    Simple methodology for the aerobic N-methylation of substituted anilines catalyzed by zirconium oxychloride octahydrate, ZrOCl2·8H 2O

    , Article Industrial and Engineering Chemistry Research ; Volume 52, Issue 32 , 2013 , Pages 11001-11006 ; 08885885 (ISSN) Tayebee, R ; Rezaei Seresht, E ; Jafari, F ; Rabiei, S ; Sharif University of Technology
    2013
    Abstract
    A highly chemoselective methodology is described for the N-methylation of functionalized anilines with dimethyl carbonate (MeOCO2Me, DMC) in the presence of ZrOCl2·8H2O. Dimethyl carbonate, which usually promotes methylation at T > 120 C and eventually under inert atmosphere, was activated in the presence of zirconium oxychloride for the desired transformation at 90 C under aerobic conditions. Aminophenols showed good reactivity in this transformation and produced the corresponding N-methylanilines, as the major products, with high selectivity. Catalyst reusability study confirmed that ZrOCl2·8H2O is a recyclable catalyst and its catalytic activity was remained unchanged at least after eight... 

    Convenient synthesis of chlorohydrins from epoxides using zinc oxide: Application to 5,6-epoxysitosterol

    , Article Heteroatom Chemistry ; Volume 20, Issue 3 , 2009 , Pages 157-163 ; 10427163 (ISSN) Matloubi Moghaddam, F ; Saeidian, H ; Mirjafary, Z ; Jebeli Javan, M ; Moridi Farimani, M ; Seirafi, M ; Sharif University of Technology
    2009
    Abstract
    Efficient synthesis of protected and unprotected chlorohydrins has been achieved by ring opening of epoxides with acetyl/benzoyl chloride and TMSCl using a catalytic amount of ZnO as a reusable catalyst. The applicability of ZnO is further extended by performing the cleavage of the natural product 5,6-epoxysitosterol with acetyl chloride. © 2009 Wiley Periodicals, Inc  

    Towards an architecture-centric approach for method engineering

    , Article IASTED International Conference on Software Engineering, SE 2008, Innsbruck, 12 February 2008 through 14 February 2008 ; February , 2008 , Pages 74-79 ; 9780889867154 (ISBN) Moaven, S ; Habibi, J ; Ahmadi, H ; Kamandi, A ; Sharif University of Technology
    2008
    Abstract
    Due to the extreme use of method engineering and increasing attention to construct methods customized for a specific project, domain, organization or a generic method compatible with the team characteristics and needs, existence of suitable and formalized frameworks and guidelines is one of the challenges method engineers are encountered. In this area, considering method construction as the goal of method engineering brings to the mind the software development process in which the product is a method adapting the method users' needs. This paper, with a new approach of applying software architecture in method engineering and making use of architecture styles, tries to take advantage of... 

    Selective oxidation of sulfides to sulfoxides by a molybdate-based catalyst using 30% hydrogen peroxide

    , Article Catalysis Communications ; Vol. 52, issue , July , 2014 , pp. 16-21 ; ISSN: 15667367 Bayat, A ; Shakourian-Fard, M ; Hashemi, M. M ; Sharif University of Technology
    Abstract
    An efficient method is reported for selective oxidation of various types of sulfides to sulfoxides and sulfones in good to high yields using 30% H 2O2 in the presence of catalytic amounts of molybdate-based catalyst in acetonitrile as solvent at room temperature. The catalyst can be easily recovered and reused for seven reaction cycles without considerable loss of activity  

    Nickel ferrite nanoparticles: An efficient and reusable nanocatalyst for a neat, one-pot and four-component synthesis of pyrroles

    , Article RSC Advances ; Volume 5, Issue 23 , Feb , 2015 , Pages 18092-18096 ; 20462069 (ISSN) Matloubi Moghaddam, F ; Koushki Foroushani, B ; Rezvani, H. R ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Abstract
    In this study nickel ferrite magnetic nanoparticles were applied as an efficient and reusable catalyst in the four-component synthesis of substituted pyrroles under neat conditions. The reaction was conducted using various amounts of catalyst at different temperatures and finally, application of 5 mol% of catalyst at 100 °C was determined as the optimum reaction condition. Results showed that nickel ferrite nanoparticles could catalyze the reaction at relatively short times (3-4 h) with high to excellent yields (70-96%). The catalyst could be recovered easily using an external magnetic field and reused nine times without any significant activity lost  

    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) Ahmadi, S. J ; 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  

    Addition of learning to critic agent as a solution to the multi-agent credit assignment problem

    , Article ICSCCW 2009 - 5th International Conference on Soft Computing, Computing with Words and Perceptions in System Analysis, Decision and Control, 2 September 2009 through 4 September 2009 ; 2009 ; 9781424434282 (ISBN) Rahaie, Z ; Beigy, H ; Sharif University of Technology
    Abstract
    Multi-agent systems (MAS) is a solution to the nowadays encountered problems, which have the characteristics such as distributiveness, dynamism and the need to adaptation, robustness, efficiency, and reusability. This paper proposed a solution to multi-agent credit assignment problem. The contribution is to equip the critic agent (who is responsible for distributing reinforcements among agents) with learning capability. Some criteria are used to propose an inner feedback to the critic. Results of simulation show the applicability of the method to a task, which has the characteristic that the agent has to decide from a large set of actions. The research is a preliminary step to more in-depth... 

    Ionic liquid-based ordered mesoporous organosilica-supported copper as a novel and efficient nanocatalyst for the one-pot synthesis of Biginelli products

    , Article Microporous and Mesoporous Materials ; Volume 204, Issue C , 2015 , Pages 269-275 ; 13871811 (ISSN) Elhamifar, D ; Hosseinpoor, F ; Karimi, B ; Hajati, S ; Sharif University of Technology
    Abstract
    The preparation, characterization and catalytic application of a novel copper-loaded ionic liquid-based periodic mesoporous organosilica (Cu@PMO-IL) are described. The mesoporous structure of the Cu@PMO-IL material is characterized by transmission electron microscopy (TEM) and nitrogen adsorption-desorption analysis. The thermal stability of the material is also determined by thermal gravimetric analysis (TGA). The presence of copper species in the material framework is confirmed by X-ray photoelectron spectroscopy (XPS) and elemental analysis (EA). The catalytic application of Cu@PMO-IL nanocatalyst is then investigated in the Biginelli condensation of different aldehydes with urea and... 

    Assortment Optimization with Demand Learning for Reusable Products

    , M.Sc. Thesis Sharif University of Technology Askari, Faezeh (Author) ; Modarres, Mohammad (Supervisor)
    Abstract
    One of the lesser-known issues in the modeling literature of assortment optimization issues is the assortment optimization for reusable products, which is an issue in various areas, including offering parking space, renting cloud computing systems resources, and rental of fashion products, etc.In this issue, we are faced with a high diversity product rental store that has a customer in each period. The seller offers a limited set of products depending on the customer demand and the inventory in hand. He can decide to rent the product or leave the system without renting the product. In case of renting the products by the customer, he may return them until the end of this period or keep them... 

    Structural Design of a Launch Vehicle with Reusable First Stage

    , M.Sc. Thesis Sharif University of Technology Hassan Jamaklu (Author) ; Haddadpour, Hassan (Supervisor)
    Abstract
    Aerodynamics loads and aeroheating during reentry, are one of the challenging issues in designing One of the main challenges in the design and application of reusable spacecrafts is the aerodynamic and thermal loads acting on their structures during reentry into the atmosphere. For this reason, all the concepts/prototypes presented in the 20th century were either not fully reusable, or were partially canceled, or did not have economic justification. In this report, the aerodynamic loads on the first stage of a launch vehicle during the launch and return phases have been investigated. Due to the fact that the main part of the first stage of the vehicle includes fuel and oxidizer tanks, the... 

    Polarity adjustment of a nanosilica-functionalized polyamine modified by ionic liquid for removal of Cu2+ from aqueous solutions

    , Article RSC Advances ; Volume 6, Issue 17 , 2016 , Pages 14128-14133 ; 20462069 (ISSN) Vafaeezadeh, M ; Mahmoodi Hashemi, M ; Ghavidel, N ; Sharif University of Technology
    Royal Society of Chemistry  2016
    Abstract
    The current work deals with modification of the surface of a silica-polyamine with amine-based ionic liquid (IL) and its application for removal of Cu2+ from an aqueous media. The absorbent is simply prepared from commercially available reagents. The material is characterized by FT-IR spectroscopy, thermogravimetric analysis (TGA), N2 adsorption-desorption, and transmission electronic microscopy (TEM). Effects of several parameters on absorption efficiency, as well as activity of the absorbent to other metals, are also investigated. Moreover, the reusability of the absorbent is studied at the optimized condition. © The Royal Society of Chemistry 2016  

    Entangled states as robust and re-usable carriers of information

    , Article Quantum Information Processing ; Volume 19, Issue 10 , 2020 Emamipanah, S ; Asoudeh, M ; Karimipour, V ; Sharif University of Technology
    Springer  2020
    Abstract
    Entangled states can be used as secure carriers of information much in the same way as carriers are used in classical communications. In such protocols, quantum states are uploaded to the carrier at one end and are downloaded from it in safe form at the other end, leaving the carrier intact and ready for reuse. Furthermore, protocols have been designed for performing quantum state sharing in this way. In this work, we study the robustness of these protocols against two of the most common sources of noise, namely de-phasing and depolarization and show that multiple uses of these carriers do not lead to accumulative errors, rather the error remains constant and under control. © 2020, Springer... 

    A formalism for recongurability analysis in distributed non-blocking components

    , Article 28th International Conference on Distributed Computing Systems Workshops, ICDCS Workshops 2008, Beijing, 17 June 2008 through 20 June 2008 ; 2008 , Pages 453-458 ; 9780769531731 (ISBN) Niamanesh, M ; Jalili, R ; Sharif University of Technology
    2008
    Abstract
    Reconfigurability for a component of a distributed component-based system means ability to replace the component with a new one, in presence of the other components. In this context, substitutability and compatibility of components should be analyzed. In this paper, we use I/O-Constraint Automata to model behavior of components and propose enough formalism for substitutability and compatibility analysis. We show that in the context of distributed non-blocking components, there is a relation weaker than usual simulation relation in automata theory for notion of substitutability. We illustrate the relation between substitutability and compatibility to reason about the reconfigurability of a... 

    CuO nanoparticles: A mild and efficient reusable catalyst for the one-pot synthesis of 4-amino-5-pyrimidinecarbonitriles under aqueous conditions

    , Article Defect and Diffusion Forum ; Volume 326-328 , 2012 , Pages 372-376 ; 10120386 (ISSN) ; 9783037854006 (ISBN) Ahmadi, S. J ; Sadjadi, S ; Hosseinpour, M ; Sharif University of Technology
    2012
    Abstract
    An efficient method for the synthesis of 4-amino-5-pyrimidinecarbonitriles by three-component reaction of malononitrile, aldehydes and N-unsubstituted amidines, under aqueous conditions, using CuO nanoparticles as catalyst is reported. The protocol offers advantages in terms of higher yields, short reaction times, and mild reaction conditions, with reusability of the catalyst  

    Process patterns for component-based software development

    , Article 12th International Symposium on Component-Based Software Engineering, CBSE 2009, East Stroudsburg, PA, 24 June 2009 through 26 June 2009 ; Volume 5582 LNCS , 2009 , Pages 54-68 ; 03029743 (ISSN); 3642024130 (ISBN); 9783642024139 (ISBN) Kouroshfar, E ; Yaghoubi Shahir, H ; Ramsin, R ; Sharif University of Technology
    2009
    Abstract
    Component-Based Development (CBD) has been broadly used in software development, as it enhances reusability and flexibility, and reduces the costs and risks involved in systems development. It has therefore spawned many widely-used approaches, such as Commercial Off-The-Shelf (COTS) and software product lines. On the other hand, in order to gain a competitive edge, organizations need to define custom processes tailored to fit their specific development requirements. This has led to the emergence of process patterns and Method Engineering approaches. We propose a set of process patterns commonly encountered in component-based development methodologies. Seven prominent component-based... 

    Integrated Robust Guidance and Control of VTVL Reusable Launch Vehicle at Terminal Phase Using Sliding Mode Control

    , M.Sc. Thesis Sharif University of Technology Asadi Azghan, Babak (Author) ; Fathi Jegarkandi, Mohsen (Supervisor)
    Abstract
    In this article, guidance and control of reusable launch vehicle at terminal phase has been studied. The goal of this article is increasing the accuracy and safety of the guidance and control system of the launch vehicle in order to successfully land on ground surface. Integrated guidance and control, being a novel method in guidance and control, is used to guide the launch vehicle in the re-entry phase and landing phase on ground surface. The returning object studied is a Falcon 9 rocket for which we find the 6 DOF model. The landing method of this vehicle is vertical. Implementing an integrated guidance and control system is a novel approach in this area. The controller used in this... 

    Synthesis, characterization and application of magnetic room temperature dicationic ionic liquid as an efficient catalyst for the preparation of 1,2-azidoalcohols

    , Article Journal of Molecular Liquids ; Volume 183 , 2013 , Pages 14-19 ; 01677322 (ISSN) Godajdar, B. M ; Kiasat, A. R ; Hashemi, M. M ; Sharif University of Technology
    2013
    Abstract
    An environmentally benign, aqueous synthesis of 1,2-azidoalcohols via regioselective ring opening of their epoxides using magnetic imidazolium based dicationic room temperature ionic liquid, [pbmim](FeCl4)2, as an efficient magnetic phase transfer catalyst in water has been described. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, high yield, easy purification and reusable catalyst  

    Two studies of framework-usage templates extracted from dynamic traces

    , Article IEEE Transactions on Software Engineering ; Volume 38, Issue 6 , 2012 , Pages 1464-1487 ; 00985589 (ISSN) Heydarnoori, A ; Czarnecki, K ; Binder, W ; Bartolomei, T. T ; Sharif University of Technology
    2012
    Abstract
    Object-oriented frameworks are widely used to develop new applications. They provide reusable concepts that are instantiated in application code through potentially complex implementation steps such as subclassing, implementing interfaces, and calling framework operations. Unfortunately, many modern frameworks are difficult to use because of their large and complex APIs and frequently incomplete user documentation. To cope with these problems, developers often use existing framework applications as a guide. However, locating concept implementations in those sample applications is typically challenging due to code tangling and scattering. To address this challenge, we introduce the notion of... 

    Commercial zinc oxide: a facile, efficient, and eco-friendly catalyst for the one-pot three-component synthesis of multisubstituted 2-aminothiophenes via the Gewald reaction

    , Article Industrial and Engineering Chemistry Research ; Volume 51, Issue 44 , October , 2012 , Pages 14577-14582 ; 08885885 (ISSN) Tayebee, R ; Ahmadi, S. J ; Rezaei Seresht, E ; Javadi, F ; Yasemi, M. A ; Hosseinpour, M ; Maleki, B ; Sharif University of Technology
    2012
    Abstract
    An eco-friendly, simple, and effective protocol is developed for the synthesis of various multisubstituted 2-aminothiophenes. In the presence of a catalytic amount of ZnO (5 mol), ketones or aldehydes, malononitrile and elemental sulfur were converted to the corresponding 2-aminothiophene derivatives in moderate to high yields (27%-70%) under solvent-free conditions at 100 °C. Zinc oxide as an efficient, readily available, and reusable catalyst, showed very good catalytic activity for the synthesis of 2-aminothiophene derivatives. Thus far, little research has been reported on the Gewald reaction under solvent-free conditions; to the best of our knowledge, this is the first time that it has... 

    Design of silica supported task-specific ionic liquid catalyst system for oxidation of cyclohexene to adipic acid with 30% H 2O 2

    , Article Catalysis Communications ; Volume 26 , September , 2012 , Pages 54-57 ; 15667367 (ISSN) Vafaeezadeh, M ; Hashemi, M. M ; Shakourian Fard, M ; Sharif University of Technology
    Elsevier  2012
    Abstract
    1-Butyl-3-methylimidazolium tungstate ([BMIm] 2WO 4) ionic liquid supported onto silica sulphamic acid demonstrated desirable performance for oxidation of cyclohexene to adipic acid. Simple experimental procedure, easy product isolation, catalyst recovery and reusability are some attractive features of this protocol