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91.
Khosrow Jadidi Ramin Ghahremanzadeh Morteza Mehrdad Mohammad Ghanbari Hamid Arvin-Nezhad 《Monatshefte für Chemie / Chemical Monthly》2008,139(3):277-280
Summary. Novel N-alkyl-4-imino-1,4-dihydro-2H-3,1-benzoxazin-2-ones were synthesized in a single step by Baeyer–Villiger oxidation of N-alkyl-3-imino-2-indolinone derivatives in high yields. The structures of the products were determined by spectral data and
by X-ray diffraction. Besides their novel structures, these compounds may have important biological activities and industrial
applications. 相似文献
92.
Najmeh Edraki Aida Iraji Omidreza Firuzi Yousef Fattahi Mohammad Mahdavi Alireza Foroumadi Mehdi Khoshneviszadeh Abbas Shafiee Ramin Miri 《Journal of the Iranian Chemical Society》2016,13(12):2163-2171
The inhibition of AKR1B10 has been recognized as a potential therapeutic approach to the treatment of various types of cancers. A novel series of compounds with imino-2H-chromen and phenylimino-2H-chromen scaffolds were synthesized by Knoevenagel condensation reaction. The in vitro cytotoxic activity of synthesized compounds was evaluated against MOLT-4 and SK-OV-3 cells. Among the tested compounds, N-(3,4-dimethoxyphenyl)-2-(phenylimino)-2H-chromene-3-carboxamide (8g) demonstrated potent inhibitory activity against both examined cell lines. The results of the molecular docking study suggested that this compound is involved in critical hydrogen-bonding interactions with the Val301 and Lue302 of AKR1B10 catalytic site. 相似文献
93.
On the Landau-Levich transition 总被引:1,自引:0,他引:1
Maleki M Reyssat E Quéré D Golestanian R 《Langmuir : the ACS journal of surfaces and colloids》2007,23(20):10116-10122
We discuss here the nature of the Landau-Levich transition, that is, the dynamical transition that occurs when drawing a solid out of a bath of a liquid that partially wets this solid. Above a threshold velocity, a film is entrained by the solid. We measure the macroscopic contact angle between the liquid and the solid by different methods, and conclude that this angle might be discontinuous at the transition. We also present a model to understand this fact and the shape of the meniscus as drawing the solid. 相似文献
94.
Shuyan Li Ramin Vatanparast Elina Vuorimaa Helge Lemmetyinen 《Journal of Polymer Science.Polymer Physics》2000,38(17):2213-2220
The curing process of hexamethylene diisocyanate‐based polyurethane has been monitored by applying FTIR and DSC methods. A general relationship between glass‐transition temperature (Tg) and conversion of curing process has been obtained. This suggests that the reaction path and the relative reaction rates are independent of the curing temperature. The reaction kinetics of the system is analyzed using the Tg data converted to the conversion of the curing process. A set of experimental data and one theoretical model of Tg versus chemical conversion are presented to prove the assumption where a direct one‐to‐one relationship between the Tg (as measured) and the chemical conversion is obtained. Apparent activation energies (Ea) obtained by applying three different methods suggest good agreement. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2213–2220, 2000 相似文献
95.
96.
Ranjbar Sara Edraki Najmeh Firuzi Omidreza Khoshneviszadeh Mehdi Miri Ramin 《Molecular diversity》2019,23(2):471-508
Molecular Diversity - 5-Oxo-hexahydroquinoline (5-oxo-HHQ) represents a biologically attractive fused heterocyclic core. Various synthetic analogs of 5-oxo-HHQ have been synthesized and assessed... 相似文献
97.
Ramin Ghorbani-Vaghei Mohammad Chegini Hojat Veisi Mehdi Karimi-Tabar 《Tetrahedron letters》2009,50(16):1861-8551
N,N,N′,N′-Tetrabromobenzene-1,3-disulfonamide [TBBDA], poly(N,N′-dibromo-N-ethyl-benzene-1,3-disulfonamide) [PBBS], and novel poly(N,N′-dibromo-N-phenylbenzene-1,3-disulfonamide) [PBPS] can be used for bromination of benzylic positions in solvent. 相似文献
98.
99.
Ramin Maleki Nasim Mohammad Nezhad Naser Samadi Khalil Farhadi 《Mikrochimica acta》2009,165(1-2):97-101
Dispersive liquid–liquid microextraction (DLLME) in conjunction with high-performance liquid chromatography-diode array detection (HPLC-DAD) has been applied to the extraction and determination of EDTA in sediments and water samples. The effect of extraction, nature and volume of disperser solvent, pH value of sample solution, extraction time and extraction temperature were investigated. Under the optimal conditions the analytical range of EDTA was from 3.0 to 50.0 μg L?1 with a correlation coefficient of 0.9982 and a detection limit of 1.7 μg L?1. The relative standard deviation (RSD) was less than 5.4% (n?=?5), and the recovery values were in the range of 89–95%. The simplicity, high enrichment, high recovery and good repeatability are the main advantages of the method presented. The DLLME-HPLC-DAD method was successfully applied to the analysis of EDTA in aqueous samples. 相似文献
100.
We present unrestricted Hartree-Fock method coupled with configuration interaction (CI) method (URHF-CI) suitable for the calculation of ground and excited states of large number of electrons localized by complex gate potentials in quasi-two-dimensional quantum dot molecules. The method employs real space finite difference method, incorporating strong magnetic field, for calculating single particle states. The Hartree-Fock method is employed for the calculation of direct and exchange interaction contributions to the ground state energy. The effects of correlations are included in energies and directly in the many-particle wave functions via CI method using a limited set of excitations above the Fermi level. The URHF-CI method and its performance are illustrated on the example of ten electrons confined in a two-dimensional quantum dot molecule. 相似文献