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581.
Research on Chemical Intermediates - An efficient one-pot synthesis of 2-aminothiazoles from methylcarbonyl and thiourea has been developed using montmorillonite-K10 as a catalyst at... 相似文献
582.
Javad Azizian Khadijeh Yadollahzadeh Hasan Tahermansouri Davood Chobfrosh Khoei Akram Sadat Delbari 《合成通讯》2013,43(14):2110-2120
Urea polyfunctional derivatives were successfully synthesized via a one-pot, five-component nucleophilic addition/Ugi reaction sequence. Simplicity, solvent-free conditions, and good yields of products are advantages of this method. 相似文献
583.
In this study, silica-supported titanium tetrachloride was prepared and used as a novel catalyst for rapid and efficient synthesis of 2,4,5-trisubstituted imidazoles by a three-component, one-pot condensation of 1,2-diketones and aryl aldehydes in excellent yield under solvent-free conditions using conventional heating or microwave irradiation.
584.
Rahmani Ali Reza Poormohammadi Ali Zamani Fahime Tahmasebi Birgani Yaser Jorfi Sahand Gholizadeh Sepideh Mohammadi Mohammad Javad Almasi Halime 《Research on Chemical Intermediates》2018,44(9):5501-5519
Research on Chemical Intermediates - Due to its high toxicity, phenol is classified as a priority. In this paper, the removal of phenol from aqueous solutions was investigated using EDTA and... 相似文献
585.
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
586.
587.
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
588.
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
589.
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
590.