• Bulletin of the Korean Chemical Society
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• 제7권5호
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• pp.407-408
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• 1986

• Bulletin of the Korean Chemical Society
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• 제19권4호
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• pp.436-439
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• 1998

An efficient synthetic method applicable for the preparation of symmetrical as well as unsymmetrical terdentates, and 2-aryl-2,2'-bipyridines was developed, in which a Michael addition of enamine onto enaminone was employed as a key step.

• Bulletin of the Korean Chemical Society
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• 제15권3호
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• pp.188-190
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• 1994

• Bulletin of the Korean Chemical Society
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• 제6권3호
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• pp.175-176
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• 1985

• 대한화학회지
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• 제9권2호
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• pp.96-100
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• 1965

우리나라 硏究用 原子爐 TRIGA Mark Ⅱ에 依한 無擔體의 Fe-59를 製造할 目的으로 分離法과 放射化學的 純度 및 核反應斷面積을 檢討하였다. 分離된 Fe-59를 ${\gamma}$-ray spectrometry와 半減期測定에 依하여 純度를 定한 結果 99.9%以上이었다.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2001년도 Australian-Korean Rheology Conference 2001
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• pp.156.5-156
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• 2001

(No abstract, see full-text)

• 한국막학회:학술대회논문집
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• 한국막학회 2004년도 추계 총회 및 학술발표회
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• pp.189-192
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• 2004

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.2963-2967
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• 2013

This paper describes a simple and efficient method involving domino Knovenegal/$6{\pi}$ electrocyclization for the preparation of a variety of 2H-pyrans using microwave irradiation under solvent- and catalyst-free conditions. This method offers the advantages of a green approach, high yields, and short reaction times. Sixteen compounds (9a-p) were obtained in good to excellent yields using the procedure.

• Mass Spectrometry Letters
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• 제14권4호
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• pp.178-185
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• 2023

QuEChERS is used worldwide as a universal sample preparation method with many benefits, such as being quick, easy, cheap, effective, rugged and safe. This study examined whether QuEChERS can be employed in isotope dilution mass spectrometry (ID-MS) for accurate analysis of pesticides in food. The ratios of fortified values and measured values of malathion and fenitrothion using the QuEChERS method were compared with those using the solid phase extract (SPE) method which was previously used in this laboratory. The separations of the two pesticides on DB-5MS and VF-1701MS columns were compared. Malathion and fenitrothion were fortified into kimchi cabbage and pretreated with the QuEChERS method and the SPE method. The results obtained using the DB-5MS column varied according to the sample preparation method, column and pesticide level. Using the VF-1701 column, ratios were 98-102% by both QuEChERS and Carb/NH₂ SPE method for all fortification level. Malathion and fenitrothion were fortified into strawberry samples for comparison with kimchi cabbage. The results for the strawberry samples indicated that the ratios were not influenced by the sample preparation methods or GC column. The QuEChERS method could be acceptable in the ID-MS method for pesticide residue analysis in food, however other conditions should be carefully considered for accurate determination, such as the column, amount of analyte and food matrix.

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.1007-1012
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• 2008

Spray pyrolysis has been found as an excellent method for the preparation of mesoporous barium sulfate at higher temperature. Ethylene glycol, a reducing agent, and solvents had good inhibition effect for the preparation of $BaSO_4$ nano particles. The $BaSO_4$ solution was sprayed at 500 & 800 ${^{\circ}C}$ using different solvents such as methanol, ethanol, propanol and n-butyl alcohol. $N_2$ adsorption-desorption isotherm revealed that $BaSO_4$ is micropore free, possessing narrow mesopores size distribution and high BET surface areas of 72.52 $m^2\;g^{-1}$ at 800 ${^{\circ}C}$ using propanol as an additive. Scanning electron microscopy (SEM) indicates that the morphology of $BaSO_4$ nano material shows uniform shell like particles. Transmission electron microscopy (TEM) proved that the resulting BaSO4 nano particles were uniform in size and the average particle size was 4-8 nm. The surface functionality and ethylene glycol peaks were assessed by Fourier transform infrared resonance (FTIR) spectroscopy. Low intensity ethylene glycol specific absorption peak was observed in propanol which proved that propanol had good inhibition effect on the structural morphology of nano particles.