Authors:Lina Han, Soo-Jin Choi, Moon-Seok Park, Seon-Myong Lee, Yu-Jin Kim, Moon-Il Kim, Binyuan Liu, and Dae-Won Park
In this study, a series of imidazolium-based ionic liquids (ILs) having carboxylic acid moieties were synthesized and used as new homogeneous catalysts to synthesize cyclic carbonates from CO2 and epoxides. Even in the absence of any co-catalyst and organic solvent, carboxylic-acid-functionalized ILs showed better catalytic activity in the coupling reaction of CO2 and styrene oxide for the production of styrene carbonate than did hydroxyl-functionalized ILs and conventional ILs without any functional moieties. A detailed investigation was carried out on a variety of factors that affected the reactivity, such as the alkyl chain length and the molecular composition of IL molecules including the halide ions. The effect of various reaction parameters such as reaction time, temperature, CO2 pressure and catalyst amount was also investigated in detail. The mechanism underlying the enhanced rate of the cycloaddition reaction in the presence of carboxylic-acid-functionalized ILs was proposed.
Authors:Yong-Sam Chung, Sun-Ha Kim, Jong-Hwa Moon, Sung-Yeol Baek, Young-Jin Kim, Hark-Rho Kim, Il-Jin Park, and Kyung-Sik Min
A fast pneumatic transfer system for an instrumental neutron activation analysis and delayed neutron counting system were
reconstructed with new designs of a functional improvement at the HANARO research reactor in 2006. The design, conception,
operation and control of these systems are described. Also the experimental characteristic parameters by a functional operation
test and an irradiation test of these systems, such as the transfer time, the neutron flux, the temperature of the irradiation
position with an irradiation time, the radiation dose rate when the rabbit is returned, etc., are reported to provide a user
information as well as for the management and safety of the reactor.