• Transactions on Electrical and Electronic Materials
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• v.10 no.3
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• pp.102-105
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• 2009

$Li[Ni_{0.2}Li_{0.2}Mn_{0.6}]O_2$ cathode materials have been synthesized by a microwave-assisted sol-gel method. The structure and electrochemical properties of $Li[Ni_{0.2}Li_{0.2}Mn_{0.6}]O_2$ were studied by X-ray difftactometry (XRD), scanning electron microscopy (SEM) and charge-discharge cycler. The powder prepared by microwave assisted sol-gel method showed good crystallinity and well-defined facet shapes. The $Li[Ni_{0.2}Li_{0.2}Mn_{0.6}]O_2$ electrode delivered a high discharge capacity of 230 $mAhg^{-1}$ at the specific current of 40 $mAg^{-1}$ (0.2 C rate) in the voltage range of 2.0${\sim}$4.8 V. About 60 % of the discharge capacity measured at 0.2 Crate (140 $mAhg^{-1}$) was maintained at a 6 C (1200 $mAg^{-1}$)rate. The cyclic property was also stable and it did not deteriorated at a high Crate.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2687-2690
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• 2009

Due to the importance of isoflavone content in soybean extracts, the microwave-assisted process (MAP) was compared to the conventional extraction methods. For comparison of the three methods, all extraction parameters (solvent, sample to solvent ratio, temperature, etc.) were kept the same; the microwave extractor was operated at 187.5 W with an emission frequency of 2450 MHz under atmospheric pressure conditions and the extractions were carried out at 75 ${^{\circ}C}$ for 3 min while the conventional reflux was at 75 ${^{\circ}C}$ for 3 h. Total yield and crude isoflavone content were determined by ultraviolet spectrophotometric and compared with the three methods. Results indicated that the MAP was comparable to the conventional method in its capability to extract target compounds without causing any degradation; in addition it dramatically reduced the extraction time from 3 h to a few minutes, suggesting that it can be an alternative technique to the time-consuming conventional reflux method.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.323-327
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• 2000

Microwave-assisted process (2,450MHz), which is known as a more environmental-friendly process with economic advantages than the current extraction methods, was investigated to pre-establish the extraction conditions for soluble ginseng components used for the processing of ginseng products. The extractions of soluble ginseng components showed optimum conditions, such as 60 mesh in particle size, 1 : 10 (g/mL) in the sample to solvent ratio, and less than 100 watts in energy efficiency. Under these conditions using along with 60% ethanol for 5 min, the overall yield of ginseng extracts was about 83%. Most soluble components including saponins were extracted by repeating five times of microwave-assisted extraction.

• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1155-1158
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• 2010

Microwave-assisted Michael reaction between EMME and various amines such as diphenylamine, 4-methyl-N-phenylbenzenamine, N-phenylnaphthalen-1-amine, dihexylamine, diisopropylamine, and 4-nitrobenzenamine were described. Solvent-free conditions on alumina as solid support in the presence of $K_2CO_3$ catalysts gave moderate to good yields (55 - 93%) of diethylmalonate analogues having enamine moieties under focused microwave irradiation.

• Journal of Environmental Science International
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• v.12 no.4
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• pp.447-459
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• 2003

This study was carried out to develop an efficient process far the elimination of phenol pollutant from soils. An microwave-assisted process (MAP) and a conventional Soxhlet extraction method (SEM) were employed to extract phenol from two types of soils. The effects of extraction methods, aged time of the spiked soil samples, extraction solvent and extraction time on the extraction performance were compared. Our results demonstrate that the recoveries from standard soil spiked were at least 10% higher fer MAP than these f3r the conventional Soxhlet. The extraction time by MAP requires significantly shelter time (1 min) than 15 h of the conventional Soxhlet. The recoveries from non-contaminated soil spiked with phenol were also almost identical f3r above results. The reduction of the extraction times with efficiency higher than that afforded by the conventional Soxhlet technique supports the suitability of the MAP method.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.199-199
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• 2006

Microwave-irradiation has become a common heat source in organic chemistry in the last decade. In recent years, polymer chemists also discovered the advances of microwave heating that include fast and efficient heating as well as the homogeneous heat profile and the easy access to pressurized reaction conditions. In this contribution, we report our investigations on the cationic ring-opening polymerization of 2-oxazolines that lead to a tremendous acceleration from several days to several minutes polymerization time. In addition, the optimized microwave-assisted polymerization procedure was applied for the preparation of libraries of diblock and triblock copolymers that were used for the determination of structure-property relationships in poly(2-oxazoline)s.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.689-691
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• 2012

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2129-2130
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• 2012

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2395-2398
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• 2010

• Journal of the Korean Electrochemical Society
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• v.15 no.4
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• pp.264-269
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• 2012

In this study, highly loaded(50 wt%) and very stable Pt/MWCNT catalysts for Polymer Electrolyte Membrane Fuel Cells(PEMFCs) are synthesized in short time scale by microwave assisted polyol method with different microwave irradiation time. The XRD and TEM results show that the Pt size becomes bigger as the microwave irradiation time increases. The mean Pt sizes of fabricated catalysts are 4.1, 4.9 and 8.5 nm when the microwave are irradiated for 10, 20 and 30 min, respectively. When compared with Pt catalyst made by conventional polyol method, it shows better long term durability due to the better Pt dispersion on the MWCNT surface.