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561.
Farzaneh Zanjanchi Nasser L. Hadipour Hassan Sabzyan Javad Beheshtian 《Journal of the Iranian Chemical Society》2013,10(5):985-999
Structural, bonding and electronic characteristics of complexes of anthraquinone and 1-arylazo-2-naphtol dyes and cellulose I β are studied using B3LYP density functional method with 6-31G** basis set based on the partially and fully optimized structures. Results reveal that for both partially and fully optimized complexes, there is a stabilizing attraction between dyes and cellulose surface. The hydrazone (Hy) tautomer in anionic state (Hy–SO3 ?) shows the strongest interaction with the cellulose surface. Natural bond orbital (NBO) and atoms-in-molecules (AIM) analyses have been carried out to study the nature of azo dyes-cellulose bonds in detail. According to NBO analysis, a remarkable charge transfer occurs between the –SO3 ? and –SO3H functional groups of the dye and the cellulose surface which can be regarded as the main source of the large dye–cellulose interaction energy. AIM analysis confirms the existence of hydrogen and van der Waals bonds between the azo dyes and cellulose. Furthermore, a very good agreement is observed between the number of hydrogen bonding sites and dye–cellulose interaction energies. 相似文献
562.
Hassan?KeypourEmail author Mohammad?Hasan?Zebarjadian Seyyed?Javad?Sabounchei 《Journal of the Iranian Chemical Society》2015,12(1):121-126
The reaction of phosphorus ylide, acetylmethylenetriparatolylphosphorane (L) with HgX2 (X = Cl, Br, I and NO3) in equimolar ratios using acetone and dimethylformamide as solvents leads to binuclear products. 31P NMR spectroscopy was used to investigate the stoichiometry and stability of a HgX2 complex with CH3COCHP(p-tolyl)3 (L) in binary acetone–dimethylformamide mixtures of varying composition. In all cases studied, the variation of 31P NMR chemical shift with the [HgX2]/[L] mole ratio indicated the formation of 1:1 complexes. The formation constants of the resulting complexes were evaluated from computer fitting of the mole ratio data to an equation that relates the observed chemical shifts to the formation constant. In all mercuric salts used, the stabilities of the resulting 1:1 complexes varied in the order Hg(NO3)2 > HgCl2 > HgBr2 > HgI2. It was found that, in the case of all complexes, an increase in the percentage of dimethylformamide in the solvent mixtures significantly decreases the stability of the complexes. 相似文献
563.
Javad Bagherian 《代数通讯》2013,41(9):3692-3704
From Burnside's pαqβ-Theorem, it follows that any nonabelian group of order pαqβ, where p and q are primes, cannot be simple. As a main result of this article, we state and prove an analog of the mentioned theorem for commutative association schemes. 相似文献
564.
At the present paper, a new system of extended general nonlinear variational inclusions is introduced and using the resolvent operator technique, equivalence between the aforesaid system and the fixed point problem is verified. By using this alternative equivalent formulation, the existence and uniqueness theorem for solution of the system of extended general nonlinear variational inclusions is demonstrated and two new iterative schemes for solving this system of extended general nonlinear variational inclusions are suggested and analyzed. The convergence analysis of the proposed iterative methods under some suitable conditions is studied. Some errors in a recent article by Noor et al. (J Inequal Appl 2011:10, 2011) are found and the incorrectness of the results of the cited paper is proved. Also, the results of the aforementioned paper are revised and corrected. 相似文献
565.
Seyed Mohammad Javad Hosseini Ataallah Soltani Goharrizi Bahador Abolpour 《Particuology》2014,(2):100-105
The design of micro-devices involving aerosol transport requires the study of the deposition of aerosols in micro-channels. In this study, the slip and no-slip boundary conditions for the gas flow regime were applied to the Navier-Stokes equations to obtain the particle deposition in simple and converging-diverging micro-channels. The equation of particle motion included inertial, viscous, Brownian, and gravity terms. It was found that the ratio of gravity to inertial effects controls the deposition of particles with diameters of 0.1-1 μm, and the ratio of diffusion to inertial effects controls the deposition of particles with diameters of 0.01-0.001 i~m. Comparison between the no-slip and slip flow regimes showed that the deposition of 0.1- to 1-μm-diameter particles was less and the deposition of 0.01- to 0.001-1μm-diameter particles was greater for the slip flow regime. There was no significant difference between slip and no-slip flow regimes for the deposition of 0.01- to 0.1-μm-diameter particles. Finally, it was shown that the stagnated gas in the corners of the converging-diverging micro-channel produced similar gas velocity profiles under the slip and no-slip flow regimes. 相似文献
566.
A comparative study of Box–Behnken, central composite, and Doehlert matrix was performed on the adsorption of Pb (II) by Robinia tree leaves in a batch system. As a case study, uptake capacity (q) and removal efficiency (R) of Pb (II) biosorption have been evaluated with all theses approaches. The advantages and limitations of these different response surface techniques have been experimentally considered. The results show the different statistical predictability of Doehlert matrix and Box–Behnken design at 95% confidence level comparable with some extent with that of central composite design at some extreme conditions. An environmental and economical comparison was also carried out between individual and simultaneous optimization of removal efficiency (R) and uptake capacity (q) using desirability function. Optimization of q proves only to have advantages over R or simultaneous optimization of R and q in this particular biosorption process. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
567.
Azardokht Mazaheri Hamid Reza Fallah Javad Zarbakhsh 《Optical and Quantum Electronics》2013,45(1):67-77
We introduced a procedure of using local density of states for increasing the quality factor and Purcell factor of photonic crystal cavities. We used multipole expansion method for accurate calculation of local density of photonic states, stationary field profile, Q-factor, mode volume and Purcell factor of photonic crystal cavities. We found out that the quality factor exponentially increases with the number of additional photonic crystal layers around the cavity while the mode frequencies stay unchanged. We also demonstrated the method in studying the defect mode??s behavior in photonic crystal cavities and showed that high Q-factor, small mode volume and high Purcell factor could be obtained with optimization of geometrical parameters of first neighboring layer. 相似文献
568.
569.
Aliasghar Jarrahpour Malihe Aye Javad Ameri Rad Saeed Yousefinejad Véronique Sinou Christine Latour Jean Michel Brunel Edward Turos 《Journal of the Iranian Chemical Society》2018,15(6):1311-1326
This paper describes the synthesis of some new β-lactam derivatives containing the 1,2,3-triazole moiety. All the compounds were evaluated for their in vitro antimicrobial and antimalarial activities. Moderate to excellent antimalarial activities were encountered. The results showed that compounds 5a, 5c, 5f, 5i exhibited the most potent antimalarial activity with IC50 values of 0.85, < 0.97, < 0.97, 1.81 µM against chloroquine-resistant P. falciparum K1 strain. A QSAR study highlights the structure–activity relationships that correlate the observed antimalarial activities with changes in the compounds’ structural features. 相似文献
570.