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Microwave engineering in Iran's academia [around the globe]
, Article IEEE Microwave Magazine ; Volume 19, Issue 3 , May , 2018 , Pages 124-128 ; 15273342 (ISSN) ; Banai, A ; Farzaneh, F ; Kamarei, M ; Moradi, G ; Rashed Mohassel, J ; Shahabadi, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
Abstract
Presents information on global MTTS society education initiatives. © 2000-2012 IEEE
An analytical approach in analysis of local oscillator near-the-carrier AM noise suppression in microwave balanced mixers
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 57, Issue 1 , 2009 , Pages 760-766 ; 00189480 (ISSN) ; Banai, A ; Farzaneh, F ; Sharif University of Technology
2009
Abstract
In this paper, a new formulation based on conversion matrix method is proposed to analyze "near-the-carrier local ocillator (LO) noise" down conversion to IF in microwave mixers. This method could be easily applied to analyze LO noise down conversion in any type of mixer. Practical results of this method have been compared with the envelope method and measurement results. It is shown that despite the conventional AM noise suppression in balanced mixers, the near-the-carrier LO noise suppression does not occur necessarily at the center frequency of hybrid in balanced mixers. AM noise suppression values are predicted precisely. © 2009 IEEE
Authors reply to comments on investigation of a class-j mode PA in presence of a second-harmonic voltage at the gate node of the transistor
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 66, Issue 7 , 2018 , Pages 3344-3344 ; 00189480 (ISSN) ; Medi, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2018
An analytical approach in analysis of local oscillator near-the-carrier AM noise suppression in microwave balanced mixers
, Article IEEE Transactions on Microwave Theory and Techniques ; Volume 57, Issue 4 , 2009 , Pages 760-766 ; 00189480 (ISSN) ; Banai, A ; Farzaneh, F ; Sharif University of Technology
2009
Abstract
In this paper, a new formulation based on conversion matrix method is proposed to analyze near-the-carrier local ocillator (LO) noise down conversion to IF in microwave mixers. This method could be easily applied to analyze LO noise down conversion in any type of mixer. Practical results of this method have been compared with the envelope method and measurement results. It is shown that despite the conventional AM noise suppression in balanced mixers, the near-the-carrier LO noise suppression does not occur necessarily at the center frequency of hybrid in balanced mixers. AM noise suppression values are predicted precisely. © 2006 IEEE
Solvent-free dehydration of alcohols using LiCI-acidicalumina
, Article Oriental Journal of Chemistry ; Volume 28, Issue 3 , 2012 , Pages 1141-1145 ; 0970020X (ISSN) ; Pourjavadi, A ; Hosseinzadeh, H ; Sharif University of Technology
2012
Abstract
Conjugated enynes, dienes and simple olefins have been cleanly and selectively synthesized, good-to-excellent yields, by dehydration of corresponding alcohols using focused microwave irradiation on the surface of LiCI-acidic alumina
Efficient and rapid route to thioamides via modified Willgerodt-Kindler reaction of quinaldine and picolines under microwave irradiation
, Article Journal of Sulfur Chemistry ; Volume 25, Issue 6 , 2004 , Pages 407-412 ; 17415993 (ISSN) ; Zali Boinee, H ; Taheri, S ; Sharif University of Technology
2004
Abstract
Various thioamides, especially thiobenzanilides and thioacetomorpholides, bearing a heterocycle ring were efficiently prepared by a modified Willgerodt-Kindler reaction of quinaldine and α- and γ-picoline with anilines and morpholine in the presence of sulfur, and a catalytic amount of DABCO under microwave irradiation
Microwave-Assisted conversion of nitriles to thioamides in solvent-free condition
, Article Synthetic Communications ; Volume 33, Issue 24 , 2003 , Pages 4279-4284 ; 00397911 (ISSN) ; Hojabri, L ; Dohendou, M ; Sharif University of Technology
2003
Abstract
Nitriles are efficiently transformed to thiomorpholides via the Willgerodt-Kindler reaction under microwave irradiation in solvent-free conditions
Preparation of conjugated enynes and arylacetylenic compounds from arylalkynols using alumina in dry media
, Article Journal of Chemical Research - Part S ; Issue 11 , 2002 , Pages 552-555 ; 03082342 (ISSN) ; Bagheri Marandi, G ; Sharif University of Technology
Scientific Reviews Ltd
2002
Abstract
Arylalkynols were converted into both conjugated enynes and arylacetylenic compounds using p-TsCl/Al2O3 and KOH/Al2O3 respectively in classical heating or microwave irradiation methods in good yields
Solvent-free rapid microwave-assisted β-elimination of sulfoxides
, Article Sulfur Letters ; Volume 24, Issue 6 , 2001 , Pages 269-273 ; 02786117 (ISSN) ; Djamshidi, H ; Sharif University of Technology
2001
Abstract
Basic silica gel (NaOH/SiO2) was found to be a very efficient media for the dehydrosulfenylation of sulfoxides in solvent-free condition under microwave irradiation
A reversible optical to microwave quantum interface
, Article Optics InfoBase Conference Papers, 19 March 2012 through 21 March 2012 ; March , 2012 ; 21622701 (ISSN) ; 9781557529398 (ISBN) ; Abdi, M ; Milburn, G. J ; Tombesi, P ; Vitali, D ; Sharif University of Technology
2012
Abstract
We describe a quantum interface between an optical and a microwave field based on their common interaction with a nano-mechanical resonator. This is an effective source of two-mode squeezing with an optical idler and a microwave signal, enabling continuous variable teleportation
KF-Al2O3 promoted synthesis of fully substituted new indeno- and naphtho-fused thiophenes under solvent-free conditions by controlled microwave heating
, Article Letters in Organic Chemistry ; Volume 4, Issue 8 , 2007 , Pages 576-584 ; 15701786 (ISSN) ; Saeidian, H ; Mirjafary, Z ; Sadeghi, A ; Sharif University of Technology
2007
Abstract
KF-Al2O3 catalyzes the reaction of arylthioacetamides with α-bromo, ketones to give fully substituted new indeno- and naphtho- fused thiophenes with good yields under solvent-free conditions by controlled microwave heating. A mechanism is proposed for the reaction course. © 2007 Bentham Science Publishers Ltd
Microwave-promoted pseudo-thia-Fries rearrangement of aryl benzylsulfonates; highly reactive benzyl cation generation
, Article Journal of Sulfur Chemistry ; Volume 25, Issue 2-3 , 2004 , Pages 125-130 ; 17415993 (ISSN) ; Hoor, A. A ; Dekamin, M. G ; Sharif University of Technology
2004
Abstract
Aryl benzylsulfonates undergo so-called pseudo-thia-Fries rearrangement under microwave irradiation. Benzylated phenolic compounds have been obtained with the loss of 'SO2' from the starting materials
Quantum interface between optics and microwaves with optomechanics
, Article 2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, CLEO/Europe-IQEC 2013, Munich, 12 May 2013 through 16 May 2013 ; 2013 ; Abdi, M ; Milburn, G. J ; Tombesi, P ; Vitali, D ; Sharif University of Technology
IEEE Computer Society
2013
Abstract
A number of schemes for a quantum interface between light at different wavelengths have been demonstrated and very recently various solutions for interfacing optics and microwaves have been proposed [1-3]. We describe here a reversible quantum interface between optical and microwave photons based on a micro-mechanical resonator in a superconducting circuit, simultaneously interacting with an optical and a microwave cavity [3]. When the cavities are appropriately driven, the mechanical resonator mediates an effective parametric amplifier interaction, entangling an optical signal and a microwave idler. Such continuous variable (CV) entanglement can be then exploited to implement CV...
Estimation of practical Inter-Modulation Rejection values in a multi-loop feed-forward microwave power amplifier using Monte-Carlo method
, Article 2007 IEEE International Conference on Telecommunications and Malaysia International Conference on Communications, ICT-MICC 2007, Penang, 14 May 2007 through 17 May 2007 ; February , 2007 , Pages 632-637 ; 1424410940 (ISBN); 9781424410941 (ISBN) ; Hemmatyar, A ; Farzaneh, F ; Sharif University of Technology
2007
Abstract
Feed-forward is one of the best methods for linearizing microwave power amplifiers, but due to device tolerance in implementation of the system components, the practical Inter-Modulation Rejection (IMR) value may differ quite much from the theoretical IMR value. One of the methods to improve the practical performance of the system is using the multi-loop configuration. Here we have introduced the multi-loop feedforward systems and we have estimated the practical IMR values of the system using Monte-Carlo analysis. As the analysis shows, although the number of components in a multi-loop system is increased with respect to a simple feed-forward system, but the difference between the practical...
Reversible optical-to-microwave quantum interface
, Article Physical Review Letters ; Volume 109, Issue 13 , September , 2012 ; 00319007 (ISSN) ; Abdi, M ; Milburn, G. J ; Tombesi, P ; Vitali, D ; Sharif University of Technology
APS
2012
Abstract
We describe a reversible quantum interface between an optical and a microwave field using a hybrid device based on their common interaction with a micromechanical resonator in a superconducting circuit. We show that, by employing state-of-the-art optoelectromechanical devices, one can realize an effective source of (bright) two-mode squeezing with an optical idler (signal) and a microwave signal, which can be used for high-fidelity transfer of quantum states between optical and microwave fields by means of continuous variable teleportation
A closed form spatial green's function for the microstrip structure using the gaussian expansion
, Article 2008 Asia Pacific Microwave Conference, APMC 2008, Hong Kong, 16 December 2008 through 20 December 2008 ; May , 2008 ; 9781424426423 (ISBN) ; Shishegar, A. A ; Sharif University of Technology
2008
Abstract
The spatial Green's function of the open microstrip structure is usually represented by the time-consuming and computationally inefficient spectral integral. This paper introduces a new closed form Green's function for the open microstrip structure by applying the GGF method. Therefore, the numerical integration of the spectral integral can be avoided entirely, leading to a considerable decrease of calculating time. Owing to the remarkable resemblances between the CI and GGF methods, for improvement of approximation especially in large distances, some useful techniques such as extraction of the surface wave poles can be carried out. Even though only an open microstrip structure with one...
Microwave-induced Cannizzaro reaction over neutral γ-alumina as a polymeric catalyst [electronic resource]
, Article Reactive and Functional Polymers ; 01/2002; 51(1):49-53 ; Soleimanzadeh, B ; Marandi, G. B
Abstract
γ-Alumina is used to catalyze the Cannizzaro reaction in the absence of any base under microwave irradiation in high yields. In the case of terephthalaldehyde the reaction is carried out with high selectivity
Microwave assisted preparation of flavylium salts with perchloric acid impregnated on silica gel under solvent-free conditions
, Article Letters in Organic Chemistry ; Vol. 11, issue. 10 , 2014 , pp. 713-718 ; ISSN: 15701786 ; Foroushani, B. K ; Ghonouei, N ; Kalahroodi, E. L ; Sharif University of Technology
Abstract
Perchloric acid immobilized on silica gel (SiO2-HClO4) has been utilized as a mild and cheap reagent for onepot preparation of different varieties of flavylium salts via tandem reaction of different acetophenones with Salicylaldehydes under solvent-free conditions. Different reaction conditions such as conventional heating and microwave irradiation have been investigated. The corresponding flavylium salts have been prepared in high yields. The procedure is milder and more convenient than the known procedures
Facile synthesis of gradient alloyed ZnxCd1- xS nanocrystals using a microwave-assisted method
, Article Journal of Alloys and Compounds ; Volume 586 , 2014 , Pages 380-384 ; Marandi, M ; Molaei, M ; Iraji-zad, A ; Taghavinia, N ; Sharif University of Technology
Abstract
We have synthesized ZnxCd1-xS nanocrystals (NCs) using a microwave assisted method. Zn(Ac)2, CdSO4 and Na2S2O3 were used as the precursors and thioglycerol (TG) was used as the capping agent. Na2S 2O3 is a photo and heat sensitive material, which supplies S species needed for the reaction upon dissociation. In this facile method, microwave irradiation provides the activation energy for the dissociation of Na2S2O3 in and leads to the formation of ZnxCd1-xS NCs in 2 min. The question that to what extent Zn is incorporated into CdS structure was addressed using UV-Vis spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Our results showed that the real value of x in...
Reconfigurable infinite impulse response (IIR) microwave-photonic filter with controllable selectivity using tunable delay line
, Article Conference on Millimeter-Wave and Terahertz Technologies, MMWaTT, 24 December 2012 through 26 December 2012 ; December , 2012 , Pages 37-39 ; 21570965 (ISSN) ; 9781467349567 (ISBN) ; Jamshidi, K ; Akbari, M ; Sharif University of Technology
2012
Abstract
A tunable IIR microwave-photonic filter (MPF) with controllable selectivity is implemented using an electrically tunable delay line. The proposed method has been experimentally tested and verified. An IIR Microwave-Photonic filter with variable Q factor in the range of 238 - 257 is realized