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We have described a novel four-component reaction (4MCR) between oxalyl chloride 1, anilines 2a–h, and two molecules of ammonium thiocyanate 3 in acetone under ultrasound irradiation to give 3-aryl-2,4-dithioxo-1,3,5-triazepane-6,7-diones. A synthetically useful ultrasound effect was observed and title products were obtained in high yields after 15–35?min sonication. Our procedure compared to the conventional heating method has the benefit of higher reaction yields and shorter reaction times. The IR spectra showed the presence of N–H, C═O and C═S groups in these compounds and 1H, 13C NMR and Mass spectral results verified their structures. Cellular investigations showed that these compounds are toxic toward cancer cells.  相似文献   
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Interaction of SOx (x?=?2,3) molecules on active sites of dianiline (as a model for polyaniline, denoted here as 2PANI) was studied using density functional theory at the BLYP-D/6-31+G(d) level of theory. Natural population analysis was used to find out the charge distribution as well as the net transferred charge of SOx upon adsorption on 2PANI and the result has been compared with Mulliken charge analysis to evaluate the sensing ability of 2PANI. The computed density of states point to the remarkable orbital hybridization between SOx and 2PANI during the adsorption process. As a consequence, the results of UV–VIS confirm the sensing ability of 2PANI toward SO2 and SO3. Based on our results, it can be found that at proper configuration the SO2 and SO3 molecules can be adsorbed on 2PANI with adsorption energies (Eads) of ?18.2 and ?62.9?kJ/mol (BSSE), respectively.  相似文献   
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Journal of Porous Materials - The development of theranostic nanostructures is one of the most advanced branches of pharmaceutical and medical sciences in the world today. Due to the unique...  相似文献   
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The sphericity and size of ammonium perchlorate (AP) particles significantly influence the properties of composite propellants. As the AP particles become more spherical, the accumulation coefficient increases, the viscosity during casting decreases, and the particle loading and burning rate increase. Hence, the production of micronized AP particles with an average size between 1 and 20 μm is important to increase the loading percentage of AP in the composite propellant. Here, the Taguchi experimental design was used to optimize the solvent-antisolvent crystallization (SAC) process for the preparation of micronized AP particles with higher sphericity. SAC parameters such as the type of antisolvent, the solvent-to-antisolvent ratio, the antisolvent temperature, the stirring speed, and the retention time were investigated at four levels. The type of antisolvent and the solvent-to-antisolvent ratio were found to mainly contribute to improving the sphericity and size of the AP particles, respectively.  相似文献   
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