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Synthesis and structure of the cyclometalated hetero-binuclear Pt-Au complexes with bridging 2-diphenylphosphinopyridine ligand
, Article Journal of Organometallic Chemistry ; Volume 786 , 2015 , Pages 14-20 ; 0022328X (ISSN) ; Jamali, S ; Sharif University of Technology
Elsevier
2015
Abstract
The heterobinuclear cyclometalated PtII-AuI complexes of the type [MePt(bhq)(μ-dppy)AuL]PF6, in which, bhq = benzo{h}quinoline, dppy = 2-diphenylphosphinopyridine, L = PPh3, 5; PPh2Me, 6; PPhMe2, 7; have been prepared by reaction of the mononuclear platinum(II) complex [MePt(bhq)(dppy)], 1, with 1 equiv. [AuL]+. Also, the reaction of complex 1 with 1 equiv AuCl(SMe2) at -60 °C gave the neutral heterobinuclear complex [MePt(bhq)(μ-dppy)AuCl], 8. All of the complexes were characterized using NMR spectroscopy and elemental microanalysis and complexes 5 and 8 were further identified by single crystal X-ray structure determination. Time-dependent density functional theory (TD-DFT) is used to...
Numerical simulation of base-isolated systems sliding on concave surfaces
, Article Asian Journal of Civil Engineering ; Volume 11, Issue 1 , 2010 , Pages 123-133 ; 15630854 (ISSN) ; Jamali, S ; Sharif University of Technology
2010
Abstract
Base isolation is an acknowledged means to reduce the transmission of earthquake accelerations from the ground into the structure. Of particular interest here are systems where the bearing slides on a concave surface which produces a self-centering force restoring the building to its original position. While the idea behind the technology is straightforward, the numerical simulation of the structural response is difficult, since the contact between the bearing and the sliding surface changes continually between sticking and sliding in a nonlinear process. The research presented here aims at developing a computational model for base-isolated building which would allow the engineer to simulate...
In situ generation of highly active bis(N-heterocyclic)carbene palladium as an efficient catalyst in direct S-arylation of methylphenyl sulfoxide and the Heck reaction: Ligand steric effects in product selectivity
, Article Applied Organometallic Chemistry ; 2016 ; 02682605 (ISSN) ; Mousavi, N ; Jamali, S ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
The use of 1,3-bis(N-heterocyclic)carbene ligands with different alkyl wingtip groups (alkyl = methyl, isopropyl and tert-butyl) is an effective method for the palladium-catalysed direct S-arylation of methylphenyl sulfoxide and C-C coupling of various of aryl halides with alkenes. The reactions proceed in moderate to good yields. Interestingly, it is shown experimentally that, by using bulkier bidentate N-heterocyclic carbene ligands, more selective catalytic systems towards cis products in Heck coupling reactions can be achieved
2,6-Bis(diphenylphosphino)pyridine: A simple ligand showing high performance in palladium-catalyzed CN coupling reactions
, Article Tetrahedron Letters ; Vol. 55, issue. 30 , July , 2014 , p. 4098-4101 ; ISSN: 00404039 ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
Abstract
The use of commercially available 2,6-bis(diphenylphosphino)pyridine as a ligand in conjunction with K2CO3, DMAc and TBAB is an effective method for the palladium-catalyzed CN coupling of a variety of aryl halides with anilines, N-heterocyclic aromatic amines, and a cyclic secondary amine. The reactions proceed in good to excellent yield (up to 98%) while the loading of Pd(OAc)2 was as low as 0.025 mol %
Climate change and hydropower in Iran's Karkheh River Basin
, Article World Environmental and Water Resources Congress 2012: Crossing Boundaries, Proceedings of the 2012 Congress ; 2012 , Pages 3341-3349 ; 9780784412312 (ISBN) ; Jamali, S ; Madani, K ; Hadian, S ; Sharif University of Technology
ASCE
2012
Abstract
The Karkheh River Basin is one of the Iranian river basins with a high potential for hydropower production. While Iran is actively constructing large dams in the Basin for hydropower production, climate change is putting the future status of hydropower production in the Basin in question. Using MODSIM, sensitivity of the Basin to climate change is investigated by estimating stream flow changes and the resulting impacts on hydropower production for different climate change scenarios. Results indicate considerable reductions in annual and seasonal hydropower production due to the expected dry climatic conditions under the existing operation rules. Findings highlight the necessity for revision...
In situ generation of highly active bis(N-heterocyclic)carbene palladium as an efficient catalyst in direct S-arylation of methylphenyl sulfoxide and the Heck reaction: Ligand steric effects in product selectivity
, Article Applied Organometallic Chemistry ; Volume 31, Issue 8 , 2017 ; 02682605 (ISSN) ; Mousavi, N. A ; Jamali, S ; Sharif University of Technology
John Wiley and Sons Ltd
2017
Abstract
The use of 1,3-bis(N-heterocyclic)carbene ligands with different alkyl wingtip groups (alkyl = methyl, isopropyl and tert-butyl) is an effective method for the palladium-catalysed direct S-arylation of methylphenyl sulfoxide and C–C coupling of various of aryl halides with alkenes. The reactions proceed in moderate to good yields. Interestingly, it is shown experimentally that, by using bulkier bidentate N-heterocyclic carbene ligands, more selective catalytic systems towards cis products in Heck coupling reactions can be achieved. Copyright © 2016 John Wiley & Sons, Ltd
Tetranuclear Au2Cu2 clusters with butterfly- and planar-shaped metal cores: strong rigidochromism induced by jahn-teller distortion in two-coordinated gold(I) centers
, Article Inorganic Chemistry ; Volume 58, Issue 18 , 2019 , Pages 12122-12131 ; 00201669 (ISSN) ; Jamali, S ; Jamjah, A ; Samouei, H ; Sharif University of Technology
American Chemical Society
2019
Abstract
Two tetranuclear Au2Cu2 cluster complexes [Au2Cu2(μ-(PPh2)2py)2(μ-OH)](PF6)3, 2, and [Au2Cu2Cl2(μ-(PPh2)2 py)2](OTf)2, 4, have been prepared by the reactions of precursor complexes [Au2(μ-(PPh2)2py)2](OTf)2, 1, and [Cu2(μ-(PPh2)2py)2(μ-SMe2)(OTf)2], 3, with [Cu(NCCH3)4]PF6 and AuCl(SMe2), respectively. The crystal structures of complexes 2 and 4 were determined by X-ray crystallography, indicating a butterfly-shaped Au2Cu2 metal core for 2 and a planar-shaped Au2Cu2 metal core for 4. In complex 2, the Cu atoms occupy the edge-sharing bond, while in complex 4, alternating Au and Cu atoms occupy the tetragon vertices. The optical properties of the complexes were investigated by experimental...
Entropy analysis and thermal optimization of nanofluid impinging jet using artificial neural network and genetic algorithm
, Article International Communications in Heat and Mass Transfer ; Volume 119 , December , 2020 ; Eghtesad, A ; Jamali, S ; Afshin, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Optimized and informed design of impinging jets can effectively enhance their rate of heat transfer. One practical pathway for such designing is to add nanoparticles to a background fluid. Here, we determine the effects of nanoparticle chemistry, their size, and their total volume fraction in water on the rate of heat transfer. We perform a comprehensive optimization using artificial neural network (ANN) and genetic algorithm (GA) to systematically study the enhanced heat transfer in nanofluids compared to pure water in obtaining a uniform cooling on a constantly heated surface in a turbulent flow. Our results indicate that increasing the size and concentration of nanoparticles enhances the...
Activation of CX (=Cl, Br) bond in aryl halides toward the palladium-catalyzed Heck reaction using 2,6-bis(diphenylphosphino)pyridine
, Article Journal of Molecular Catalysis A: Chemical ; Volume 366 , January , 2013 , Pages 30-35 ; 13811169 (ISSN) ; Nadri, S ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
2013
Abstract
The 2,6-bis(diphenylphosphino)pyridine/palladium catalytic system successfully catalyzes the Heck coupling reaction of less reactive aryl chlorides as well as aryl bromides with styrene to give the corresponding olefins in reasonable yields. TBAB (tetrabutylammoniumbromide) as an additive was found to be essential for these reactions. The results of Heck reaction exhibited a high selectivity (>99/1) favoring the trans product
Performance evaluations and comparisons of several LDPC coded MC-FH-CDMA systems
, Article Scientia Iranica ; Volume 13, Issue 4 , 2006 , Pages 337-347 ; 10263098 (ISSN) ; Haghighat, J ; Nasiri Kenari, M ; Jamali, S. H ; Sharif University of Technology
Sharif University of Technology
2006
Abstract
In this paper, the application of regular Low-Density Parity-Check (LDPC) codes in Multi-Carrier Frequency-Hopping (MC-FH) CDMA systems is studied. To this end, different well-known constructions of regular LDPC codes are considered and the performance of LDPC coded MC-FH-CDMA systems, based on these constructions, are evaluated and compared in a frequency-selective slowly Rayleigh fading channel. These results are compared with those previously reported for super-orthogonal convolutionally coded MC-FH-CDMA systems. The simulation results indicate that the LDPC coded MC-FH-CDMA system significantly outperforms the uncoded and super-orthogonal convolutionally coded schemes. To alleviate the...
Performance evaluation of LDPC coded MC-FH-CDMA system over fading channels
, Article 14th IEEE 2003 International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC2003, Beijing, 7 September 2003 through 10 September 2003 ; Volume 2 , 2003 , Pages 1574-1578 ; 0780378229 (ISBN); 9780780378223 (ISBN) ; Haghighat, J ; Nasiri Kenari, M ; Jamali, S. H ; Sharif University of Technology
2003
Abstract
In this paper, we consider the application of Low-Density Parity-Check (LDPC) codes in multi-carrier frequency-hopping (MC-FH) CDMA systems. We evaluate the performance of the coded system in a slowly Rayleigh fading frequency-selective channel using different construction methods of regular LDPC codes. We then compare the results with those of the Super-Orthogonal coded system. Our simulation results show that the LDPC coded scheme significantly outperforms the uncoded and the Super-Orthogonal coded scheme. Finally, we propose a new semi-random construction of regular LDPC code and evaluate its performance in MC-FH-CDMA system. Our numerical results indicate that this new construction...
High-performance LDPC codes for CDMA applications
, Article 4th International Workshop on Mobile and Wireless Communications Network, MWCN 2002, 9 September 2002 through 11 September 2002 ; 2002 , Pages 105-109 ; 0780376056 (ISBN); 9780780376052 (ISBN) ; Jamali, S. H ; Behroozi, H ; Nasiri Kenari, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2002
Abstract
Recently, V. Sorokine et al. (see IEEE Trans. Commun., vol.48, no.10, p.1660-8, 2000; vol.48, no.11, p.1818-28, 2000) have introduced a class of low-density parity-check (LDPC) codes which, when applied on an IS-95 CDMA system, show, at BER=10-3, a five-fold and two-fold increase in capacity compared to the traditional uncoded scheme and to state-of-the-art low-rate orthogonal convolutional codes, respectively. However, these codes suffer from an error-floor at lower BERs which are needed for high-quality services, such as data. To enhance the capacity of CDMA systems, not only for moderate BER values but also for lower BER values, we modify the construction of these codes slightly, to...
Study the effect of architectural modification on fracture behavior of Al-DRA composite [electronic resource]
, Article Mechanics of Advanced Materials and Structures ; September 2014, Volume 21, Issue 8, pages 662-668 ; Khalili, S ; Bagheri, R ; Simchi, A. (Abdolreza) ; Sharif University of Technology
Abstract
An architectural modification method was utilized to improve fracture toughness of discontinuously reinforced aluminum (DRA) composites. Al-DRA composites having a structure similar to that of reinforced concrete were fabricated. The number of reinforcing DRA rods within Al matrix and volume fraction of SiC particles in DRA were altered to evaluate their effect on fracture behavior of these materials. It was found that architectural modification does not have any destructive influence on elastic modulus and yield strength of the composite. Moreover, the success of this method on toughness improvement strongly depends on the occurrence of debonding between Al and DRA regions upon loading
ONO pincer type binuclear Pd(II) complex: Synthesis, crystal structure and catalytic utilization of the resulting organopalladium complex in catalytic copper-free Sonogashira coupling reaction
, Article Inorganica Chimica Acta ; Volume 451 , 2016 , Pages 227-232 ; 00201693 (ISSN) ; Mousavi, N. A ; Zare, M ; Jamali, S ; Ellern, A ; Woo, L. K ; Sharif University of Technology
Elsevier S.A
2016
Abstract
New binuclear palladium (II) complex featuring ONO pincer type hydrazone ligand was synthesized and characterized by spectroscopic and single-crystal XRD analysis. This complex showed excellent catalytic activity towards the copper-free Sonogashira cross coupling reaction. The main advantages over previous methodologies include low catalyst loading, less problematic reaction media (H2O–DMSO) and reusability in homogenous systems for optimal performance
Bis-N-Heterocyclic carbene complexes of coinage metals containing four naphthalimide units: a structure-emission properties relationship study
, Article Inorganic Chemistry ; Volume 60, Issue 17 , 2021 , Pages 12924-12933 ; 00201669 (ISSN) ; Jamali, S ; Chabok, S. M. J ; Jamjah, A ; Samouei, H ; Jamshidi, Z ; Sharif University of Technology
American Chemical Society
2021
Abstract
Naphthalimide derivatives provide highly versatile self-assembled systems and aggregated forms with fascinating emission properties that make them potential candidates for many applications such as bioimaging and sensing. Although various aggregated species of naphthalimide derivatives have been well documented, little is known about the correlation between their structure and photophysical properties. Here the preparation of a series of tetrameric naphthalimide molecules in which naphthalimide units are linked by bis-N-heterocyclic carbene complexes of coinage metals is described. An in-depth structural investigation into these tetramers has been carried out in solution and the solid state...
Metal-Organic cubane cage with trimethylplatinum(Iv) vertices
, Article Inorganic Chemistry ; 2021 ; 00201669 (ISSN) ; Jamali, S ; Mahmoudi, S ; Samouei, H ; Nayeri, S ; Chabok, S. M. J ; Jamshidi, Z ; Sharif University of Technology
American Chemical Society
2021
Abstract
Herein we describe the synthesis and characterization of the first platinum(IV) metal-organic cage [(Me3PtIV)8(byp)12](OTf)8 (2), in which the organometallic moieties trimethylplatinum(IV) (PtMe3) occupied the corners of a cubane structure and 4,4′-bipyridine ligands used as linkers. The first-principles density functional theory calculations showed that the highest occupied molecular orbitals were localized on the PtMe3 moieties, while the lowest unoccupied molecular orbitals were distributed on the organic linkers. © 2021 American Chemical Society
Apathy exacerbates postural control impairments in stroke survivors: The potential effects of cognitive dual-task for improving postural control
, Article Neuropsychologia ; Volume 174 , 2022 ; 00283932 (ISSN) ; Mehdizadeh, H ; Azad, A ; Cheraghifard, M ; Jamali, S ; Davoudi, M ; Shokouhyan, S. M ; Taghizadeh, G ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Apathy is a stressor and debilitating common condition for both stroke survivors and their caregivers. However, its effects on the postural control of these patients have not yet been investigated. Improved postural stability through withdrawing attention from postural control by concurrent cognitive task (i.e. dual-task condition) has been reported previously, but the effect of apathy, as a confounding factor, remains unknown. This study aimed to examine the effects of apathy and dual-task condition on postural control of chronic stroke survivors from biomechanical and neurophysiological perspectives. Twenty non-apathetic stroke survivors, 20 apathetic stroke survivors, and 20 sex-, age-,...
Metal-Organic cubane cage with trimethylplatinum(IV) vertices
, Article Inorganic Chemistry ; Volume 61, Issue 1 , 2022 , Pages 15-19 ; 00201669 (ISSN) ; Jamali, S ; Mahmoudi, S ; Samouei, H ; Nayeri, S ; Chabok, S. M. J ; Jamshidi, Z ; Sharif University of Technology
American Chemical Society
2022
Abstract
Herein we describe the synthesis and characterization of the first platinum(IV) metal-organic cage [(Me3PtIV)8(byp)12](OTf)8 (2), in which the organometallic moieties trimethylplatinum(IV) (PtMe3) occupied the corners of a cubane structure and 4,4′-bipyridine ligands used as linkers. The first-principles density functional theory calculations showed that the highest occupied molecular orbitals were localized on the PtMe3 moieties, while the lowest unoccupied molecular orbitals were distributed on the organic linkers. © 2021 American Chemical Society
A rare type of Rhenium(I) diimine complexes with unsupported coordinated phosphine oxide ligands: Synthesis, Structural Characterization, Photophysical and theoretical study
, Article European Journal of Inorganic Chemistry ; Volume 2019, Issue 39-40 , 2019 , Pages 4350-4357 ; 14341948 (ISSN) ; Jamali, S ; Pavlovskiy, V. V ; Porsev, V. V ; Evarestov, R. A ; Kisel, K. S ; Koshevoy, I. O ; Shakirova, J. R ; Tunik, S. P ; Sharif University of Technology
Wiley-VCH Verlag
2019
Abstract
This paper presents synthesis and photophysical investigation of a very rare type of the ReI diimine complexes, [Re(diimine)(CO)3(OPR3)]+, R = Ph, Cy; diimine – phenanthroline and neocuproine, containing monodentate (unsupported) phosphine oxide ligands. The obtained compounds have been structurally characterized in solid phase by using XRD crystallography, which revealed unusual distortions in the pseudo octahedral rhenium environment, which may be ascribed to intramolecular interligand (phosphine oxide – diimine) interaction rather than to crystal packing effect. Optimization of the ground state structure of these molecules with the DFT method also confirmed intramolecular origin of the...
Pt-M (M = Au and Tl) Dative Bonds Using Bis(cyclometalated)platinum(II) Complexes
, Article Organometallics ; Volume 38, Issue 8 , 2019 , Pages 1709-1720 ; 02767333 (ISSN) ; Jamali, S ; Naseri, S ; Jamjah, A ; Kia, R ; Samouei, H ; Mastrorilli, P ; Shahsavari, H. R ; Raithby, P. R ; Sharif University of Technology
American Chemical Society
2019
Abstract
Symmetrical and unsymmetrical biscyclometalated platinum(II) complexes [Pt(ptpy)2], 1, and [Pt(ptpy)(bppy)], 2, in which ptpy = deprotonated 2-(p-tolyl)pyridine and bppy = deprotonated 2-(3-bromophenyl)pyridine, have been prepared from the reaction between tris(pentafluorophenyl)borane, B(C6F5)3 and 1 equiv of monocyclometalated complexes [PtMe(ptpy)(ptpyH)], B, and [PtMe(ptpy)(bppyH)], C, respectively. The solid-state structures of 1 and 2 have been determined by X-ray crystallography. The reaction of 1 with 1 equiv of TlPF6 or [Au(PPh3)]OTF resulted in the production of heteronuclear complexes [Pt(ptpy)2Tl]PF6, 3 and {Pt(ptpy)2[Au(PPh3)]}OTF, 4, respectively. X-ray diffraction data showed...