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Tehran, Iran

Payame Noor University is a public university and one of the largest universities in Iran, with its headquarters based in Tehran, 31 provincial centers, 485 local study centers, other campuses all around the country, and one International Study Center located in the headquarters in Tehran. Established in 1988, is a legal body under the Ministry of Science, Research and Technology.PNU took its first intake at 5 study fields at 28 local study centers. Presently, the university has 3,500 academic members and 1,101,182 national and international students.Its name means "The message of Light" in Persian. Wikipedia.

Veisi H.,Payame Noor University
Current Organic Chemistry

In this review, the use of molecular iodine as a catalyst in the synthesis of heterocyclic compounds is presented and reviewed. In recent years, the use of molecular iodine in organic chemistry has received considerable attention because the chemical (a) is inexpensive and readily available, (b) is less toxic than alternatives, (c) has an easy workup method, and (d) is a moisture-stable, mild Lewis acid. Many of the reactions using iodine are associated with mild conditions, greater stero- and regioselectivities, short reaction times, and simplicity in their operation. © 2011 Bentham Science Publishers Ltd. Source

Mohseni M.,Payame Noor University
General Relativity and Gravitation

We obtain generalized Raychaudhuri equations for spinning test particles corresponding to congruences of particle’s world-lines, momentum, and spin. These are physical examples of the Raychaudhuri equation for a non-normalized vector, unit time-like vector, and unit space-like vector. We compute and compare the evolution of expansion-like parameters associated with these congruences for spinning particles confined in the equatorial plane of the Kerr space-time. © 2015, Springer Science+Business Media New York. Source

This paper describes the synthesis and characterization of novel type poly (4-chloromethyl styrene-graft-4-vinylpyridine)/TiO2 nanocomposite. Firstly, poly (4-chloromethyl styrene)/TiO2 nanocomposite was synthesized by in situ free radical polymerizing of 4-chloromethyl styrene monomers in the presence of 3-(trimethoxysilyl) propylmethacrylate (MPS) modified nano-TiO2. Thereafter, 1-hydroxy-2,2,6,6-tetramethyl-1- piperidinyloxy (TEMPO-OH) was synthesized by the reduction of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO). This functional nitroxyl compound was covalently attached to the poly (4-chloromethyl styrene)/TiO2 with replacement of chlorine atoms in the poly (4-chloromethyl styrene) chains. The controlled graft copolymerization of 4-vinylpyridine was initiated by poly (4-chloromethyl styrene)/TiO2 nanocomposite carrying TEMPO groups as a macroinitiators. The coupling of TEMPO with poly (4-chloromethyl styrene)/TiO2 was verified using 1H nuclear magnetic resonance (NMR) spectroscopy. The obtained nanocomposites were studied using transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectra, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and the optical properties of the nanocomposites were studied using ultraviolet-visible (UV-Vis) spectroscopy. © 2011 Elsevier Ltd. All rights reserved. Source

Asgarani S.,Payame Noor University
Physica A: Statistical Mechanics and its Applications

In this paper, by considering the first three Khinchin axioms (K1-K3) and neglecting the fourth (K4), a set of new three-parameter entropies will be introduced which are expressed in terms of a generalized incomplete Gamma function as Sd,c1,c2[p]∝∼iΓ(d+1,1-c 1lnpi,1-c2lnpi). Also, its asymptotic behavior will be found and it will be shown that, for some special values of parameters, some known entropies like Tsallis, Kaniadakis and Abe entropies are recovered. © 2012 Elsevier B.V. All rights reserved. Source

Eftekhari-Sis B.,Islamic Azad University at Maragheh | Zirak M.,Payame Noor University
Chemical Reviews

Most heterocycles exhibit biological activity, including antitumor, anti-HIV, antibiotic, antidepressant, antiinflammatory, antiviral, antidiabetic, antimalarial, antimicrobial, antibacterial, antifungal, herbicidal, fungicidal, and insecticidal activities. Additionally, they have important applications in organic synthesis as organocatalysts, synthetic intermediates, chiral auxiliaries, and metal ligands in asymmetric catalysis. Therefore, the development of new efficient methods to synthesize heterocycles is of considerable interest. Pyrazole and pyrazoline derivatives have received great attention because of their interesting biological activities, such as antibacterial, antiviral, antidiabetic, antitubercular, antitumor, anti-inflammatory, and antidepressant activities. Source

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