3 research outputs found

    Stationary State Solutions of a Bond Diluted Kinetic Ising Model: An Effective-Field Theory Analysis

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    We have examined the stationary state solutions of a bond diluted kinetic Ising model under a time dependent oscillating magnetic field within the effective-field theory (EFT) for a honeycomb lattice (q=3)(q=3). Time evolution of the system has been modeled with a formalism of master equation. The effects of the bond dilution, as well as the frequency (ω)(\omega) and amplitude (h/J)(h/J) of the external field on the dynamic phase diagrams have been discussed in detail. We have found that the system exhibits the first order phase transition with a dynamic tricritical point (DTCP) at low temperature and high amplitude regions, in contrast to the previously published results for the pure case \cite{Ling}. Bond dilution process on the kinetic Ising model gives rise to a number of interesting and unusual phenomena such as reentrant phenomena and has a tendency to destruct the first-order transitions and the DTCP. Moreover, we have investigated the variation of the bond percolation threshold as functions of the amplitude and frequency of the oscillating field.Comment: 8 pages, 4 figure

    Synthesis, characterization and biological activity of 2-methyl-3-aminoquinazolin-4(3H)-ones Schiff bases

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    The 3-amino-2-methylquinazoline/6-bromo-2-methylquinazoline-4(3H)-ones, 2a,b, on treatment with 2,3-indolinedione in the presence of traces of glacial acetic acid yielded 3-{(2'-oxo-1',2'-dihydroindole-3'-ylidene)amino} -2-methylquinazolin/6-bromo-2-methylquinazolin-4-(3H)-ones, 3a,b, which on condensation with various secondary amines and formaldehyde in ethanol afforded title compounds 3-{(1'-alkyl/arylaminomethyl-2'-oxo-1',2'-dihydroindole-3'-ylidene)amino} -2-methyl-6-quinazolin-4-(3H)-ones, 4a1-6 and 4b1-6. C, H, N analysis, infrared spectroscopy, ¹H NMR, and mass spectroscopy allowed the identification of the synthesized compounds, which were investigated for their antimicrobial, analgesic, anti-inflammatory and antihelmintic activities. The results of the biological activities revealed that the compounds 4a3, 4a4 and 4b6 exhibited significant analgesic and anti-inflammatory activities. Compounds 4b5 and 4b6 showed antihelmintic activity when tested against Pheretima posthuma
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