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Rafati S.,Sayyed Jamaleddin Asadabadi University | Karimi M.,University of Tehran
Theoretical and Applied Climatology

In this research, the spatial and temporal distribution of Mesoscale Convective Systems was assessed in the southwest of Iran using Global merged satellite IR brightness temperature (acquired from Meteosat, GOES, and GMS geostationary satellites) and synoptic station data. Event days were selected using a set of storm reports and precipitation criteria. The following criteria are used to determine the days with occurrence of convective systems: (1) at least one station reported 6-h precipitation exceeding 10 mm and (2) at least three stations reported phenomena related to convection (thunderstorm, lightning, and shower). MCSs were detected based on brightness temperature, maximum areal extent, and duration thresholds (228 K, 10,000 km2, and 3 h, respectively). An MCS occurrence classification system is developed based on mean sea level, 850 and 500 hPa pressure patterns. The results indicated that the highest frequency of MCSs occurred in December and April. Assessment of MCSs spatial frequency showed that MCS occurrence is strongly correlated with topography in April and May unlike the cold months. In other words, the role of Zagros Mountains in developing MCSs varies based on the season so that its impact increases with enhancement of mean monthly temperature. In addition, the occurrence of MCSs depends closely on the configuration of the Sudan Low in the southwest of Iran. © 2016 Springer-Verlag Wien Source

Moosavi-Zare A.R.,Sayyed Jamaleddin Asadabadi University | Zolfigol M.A.,Bu - Ali Sina University | Noroozizadeh E.,Bu - Ali Sina University

1,3-Disulfonic acid imidazolium chloride ([Dsim]Cl), as a Brønsted acidic ionic liquid, is introduced for the sulfonation of aromatic compounds by in situ generation of sulfuric acid at 50 °C under mild conditions and in aqueous medium. Copyright © 2016, Georg Thieme Verlag. All rights reserved. Source

Moosavi-Zare A.R.,Sayyed Jamaleddin Asadabadi University | Zolfigol M.A.,Bu - Ali Sina University | Rezanejad Z.,Bu - Ali Sina University
Canadian Journal of Chemistry

An efficient protocol for the synthesis of 2,4,6-triarylpyridines and 3-(2,6-diarylpyridin-4-yl)-1H-indoles by the one-pot pseudo four component condensation reaction of aldehydes with acetophenones and ammonium acetate in the presence of Ph3CCl under neutral and solvent-free conditions has been reported. Mechanistically, it is interesting that trityl chloride by in situ generation of trityl carbocation (Ph3C+) promotes the reaction. In this work, seven products have been reported for the first time. © 2016 Published by NRC Research Press. Source

Zolfigol M.A.,Bu - Ali Sina University | Baghery S.,Bu - Ali Sina University | Moosavi-Zare A.R.,Sayyed Jamaleddin Asadabadi University | Vahdat S.M.,Islamic Azad University at Amol
Journal of Molecular Catalysis A: Chemical

Pyrazine-1,4-diium trinitromethanide {[1,4-DHPyrazine][C(NO2)3]2} as a green and novel nano-structured molten salt catalyzed the synthesis of new 1-(α-aminoalkyl)-2-naphthol derivatives via the one-pot three-component condensation reaction between 2 or 4-aminopyridine, aromatic aldehydes and β-naphthol at room temperature under solvent-free conditions in comparison with Ag-TiO2 nano composite. Some advantages of the offered method are excellent cost effectiveness, catalytic efficiency, recycle and reusability of the catalyst. Pyrazine-1,4-diium trinitromethanide {[1,4-DHPyrazine][C(NO2)3]2} was fully characterized by IR, 1H NMR, 13C NMR, mass, thermal gravimetry (TG), derivative thermal gravimetry (DTG), differential thermal (DTA), X-ray diffraction patterns (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis. © 2015 Elsevier B.V. All rights reserved. Source

Khazaei A.,Bu - Ali Sina University | Abbasi F.,Bu - Ali Sina University | Moosavi-Zare A.R.,Sayyed Jamaleddin Asadabadi University
Research on Chemical Intermediates

Abstract: A new N-bromo sulfonamide reagent, namely N,2-dibromo-6-chloro-3,4-dihydro-2H-benzo[e][1,2,4]thiadiazine-7-sulfonamide 1,1-dioxide, was synthesized and used as a new and highly efficient catalyst for the preparation of 9-aryl-1,8-dioxo-octahydroxanthene derivatives by the condensation reaction of dimedone (5,5-dimethylcyclohexane-1,3-dione) and various arylaldehydes. Mechanistically, it is interesting that in situ generation of the Br+ ion from the catalyst is successfully catalyzed by this reaction under neutral media. Graphical Abstract: [Figure not available: see fulltext.] © 2016 Springer Science+Business Media Dordrecht Source

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