• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.534-539
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• 1997

In order to reuse enzyme efficiently, a mthod for ionic binding of fructosyltransferase to a porous carrier bearing quaternary alkyl alkanolammonium groups was investigated. The fructosyltransferase activity of the immobilized enzyme increased with increasing amount of loaded enzyme, and maximally reached 770U/g of the carrier when loaded amount of the enzyme was 18.2 mg/g carrier. The immobilized fructosyltransferase had optimum pH and temperature of 7.5 and 45$^{\circ}C$, respectively, whereas soluble enzyme had 6.5 and 55$^{\circ}C$: the Km value for the immobilized enzyme was 27.8 mM for sucrose, which was the same as that of soluble enzyme. In a batch reactor, the enzyme produced a mixture of fructooligosaccharides, mainly F$_2$G, from sucrose with the slight loss of enzyme activity during continuous operation of 12 days at 42$^{\circ}C$.

• The Korean Journal of Quaternary Research
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• v.15 no.2
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• pp.111-117
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• 2001

The deep cored sediments of the beach spit deposit in the inlet of the Songji lagoon(lake) have been studied in terms of the late Quarternary stratigraphy and relationship of the Holocene sea-level curve. Furthermore, the total content of heavy mineral sands from the established stratigraphic units(Unit I, II and III) varies due to the changes of depositional environments from continental to marine condition.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2468-2473
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• 2018

Nitrogen-doped activated carbon fibers (ACFs) were prepared by chemical vapor deposition using melamine powder and acetonitrile for introducing quaternary nitrogen on the commercial ACFs, subsequently heated at $950^{\circ}C$ and activated by steam. Adsorption experiments of nitrate in aqueous solution were also conducted to evaluate adsorption capacity of the prepared ACFs using ion chromatography. The amount of introduced nitrogen content and nitrogen species on activated carbon fibers was examined by CHN elemental analyzer and X-ray photoelectron spectroscopy, respectively. As a result, adsorption capacity of quaternary nitrogen-doped ACF (ST-ML-AN-ST) was 0.75 mmol/g, indicating ca. two-times higher than that of untreated ACF (0.38 mmol/g). According to the adsorption data, the Langmuir isotherm model was the best fit. The prepared samples were also regenerated using hydrochloric acid. After regeneration, the adsorption capacity of the nitrogen-doped ACF (ST-ML-AN-ST) showed ca. 80% on average, implying that a portion of nitrates was adsorbed on the prepared ACFs irreversibly.

• The Korean Journal of Quaternary Research
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• v.3 no.1
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• pp.69-85
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• 1989

The depositional environments of the Pyung-Ahn Group sedimentary rocks, Jeongseon-Kun, Kangweondo, Korea are investigated. The environments are understood to be characteristic transitional from a typical shallow marine to a typical continental environment. Such transitional conditions are also understood in various parts of Quaternary and modern environment on the earth. In particular, the absence of detrital feldspar sand grains in the Manhang and Keumcheon Formation Sandstone body is described firstly in Korea, and the fact and possible mechanism are discussed.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1545-1548
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• 2007

This paper discusses the racemic and stereoselective synthetic route for novel 4'α -methyl and 6'α -methyl analogues of abacavir. The quaternary carbon at the 4'-position of carbocyclic nucleoside was installed successfully via a Claisen rearrangement. The stereocontrolled construction of a methyl group in the 6'α - position was directed through the Felkin-Anh rule. A Bis-vinyl compound 9 was cyclized successfully using Grubbs' catalyst II to provide a carbocycle nucleus for the target compound. The synthesized compound 15 showed moderate anti-HIV activity (EC50 = 10.67 μM, MT-4 cell lines).

• YAKHAK HOEJI
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• v.25 no.4
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• pp.199-204
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• 1981

The methanol extract of Thalictrum uchiyamai Nakai was fractionatedi nto four parts; (1) ether soluble nonphenolic fraction (2) phenolic tertiary bases fraction, (3) chloroform soluble tertiary bases fraction and (4) aqueous quaternary bases fraction. The fractions of this plant showed a total of twenty-four spots on the silica gel TLC. Ether soluble nonphenolic fraction and ether soluble phenolic fraction showed nine alkaloid spots respectively, chloroform soluble fraction showed three alkaloid spots and quaternary bases fraction showed three alkaloid spots. The antimicrobial activity of the four extracts was shown as follows; nonphenolic tertiary bases inhibited the growth of Micrococcus dutica at the concentration of $50\mu$g/ml, in phenolic tertiary bases $500\mu$g/ml concentration was inhibitory to Micrococcus dutica and to Staphyloccus aureus. In aqueous quaternary bases, $500\mu$g/ml concentration was inhibitory to Klebsiella pneumonae. Chloroform soluble tertiary fraction showed slight activity. All of bases showed reproducible activity against tested microorganisms.

• The Korean Journal of Quaternary Research
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• v.1 no.1
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• pp.21-34
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• 1987

In the present study area, a part of intertidal flat in the Seosan Bay, west coast of Korea, characteristic three dominant tidal sedimentary facies and their related several typical sedimentary structures are described, Furthermore, a possible interpretation about the time stratigraphic developments of these intertidal deposits is suggested by introducing very late Quaternary (Holocene) sea-level rise in Korean Seas.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.14 no.1
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• pp.16-37
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• 1988

A new quaternary ammonium compound, hydrolyzed ginseng-sapoin quaternary (HGSQ), from hydrolyzed Korean ginseng-saponin and 2, 3-epoxypropyltrimethyl ammonium chloride has been developed as a conditioning agent for hair care products. This structure has the hydrophilic group from the introduced cationic and the hydrophobic group from the aglycone of ginseng saponin. Its properties: surface tension, conductivity, critical micelle concentration, eye irritation, sorption onto hair, force reduction (%) for 20% extension and moisture retention effect comparing with the commercial standards. Also half-head tests of HGSQ-containing shampoo were carried out to compare the conditioning effects in shampoos.

• Journal of Communications and Networks
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• v.12 no.4
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• pp.330-333
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• 2010

In this paper, using binary (N, M, L, $\epsilon$) low correlation zone (LCZ) sequence sets, we construct new quaternary LCZ sequence sets with parameters (2N, 2M, L, $2{\epsilon}$). Binary LCZ sequences for the construction should have period $N\;{\equiv}\;3$ mod 4, L|N, and the balance property. The proposed method corresponds to a quaternary extension of the extended construction of binary LCZ sequence sets proposed by Kim, Jang, No, and Chung [1].

• The Korean Journal of Quaternary Research
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• v.9 no.1
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• pp.61-86
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• 1995

칠레 북부해안에는 여러개의 해안 단구들이 발견되는데 이는 지구조 운동과 하께 해수면 변동과 밀접한 관련이 있다, 단구의 형성시기는 전부 밝혀지지는 않았으며 여전히 논란이 되고 있다,. 안토파가스타에서 이끼케까지 9개지역에서 발견되는 여러단구에 대한 탄 소 연대측정 전자스핀 공명법, 우라늄측정, 아미노산 연대측정 방법들을 이용하여 그 형성시 기를 측정하였다, 그결과들은 기본적으로 3∼4개의 뚜렷한 단구를 선정하여 지역간에 서로 대비하였다, 대부분의 단구들은 산소 동위연소 연대(Oxygen Isotope State) 3에서 11범주에 들어가는데 이것은 계단식 단구들이 단지 지구조 운동만으로 형성된 것이 아니라 전지구 기 후 변동과 밀접하게 관련된 전세계 해수면 변동에 의해 강한 영향을 받았음을 시사한다. 특 히 플라이스토세에 형성된 일련의 해빈 사구들은 플라이스토세 초기에서 중기사이 반복된 간빙기를 나타낸다.