• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.121.2-121.2
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• 2007

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• Kyungpook Mathematical Journal
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• v.59 no.3
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• pp.525-535
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• 2019

In relation to the generalized Tanaka-Webster connection, we consider a new notion of parallel structure Jacobi operator for real hypersurfaces in complex two-plane Grassmannians and prove the non-existence of real hypersurfaces in $G_2({\mathbb{C}}^{m+2})$ with generalized Tanaka-Webster parallel structure Jacobi operator.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.126-146
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• 2000

To develop and evaluate formaldehyde measurement method using 2,4-dinitro-phenylhydrazine (2,4-DNPH) coated sampler and gas chromatography, laboratory test and field test were conducted. Results of this study are as follows. Limit of detection(LOD) of measurement methods, HPLC-UVD, GC-NPD and GC-FID, is $0.008{\mu}g/m{\ell}$ $0.060{\mu}g/m{\ell}$, $0.472{\mu}g/m{\ell}$ respectively. Coefficiency of measurement methods, HPLC-UVD, GC-NPD and GC-FID, is 0.008, 0.009, 0.020 respectively. Desorption efficiency of sep-pak xposure aldehyde sampler and sorbent sample tube is 1.05(range : 0.99 - 1.12), 1.02(range : 0.99 - 1.06) respectively. Samples of sorbent sample tube and sep-pak xposure aldehyde sampler turned out to be stored at refrigerator, according to storage test results. Measurement methods of HPLC-UVD, GC-NPD, GC-FID, according to results of precision for the combined sampling and analytical procedure, became acceptable to OSHA evaluation standard. Field test using exposure chamber met the NIOSH overall uncertainty recommendation(less than 25%). Overall uncertainty of Sepak-HPLC(UVD), Tube-GC(NPD), Tube-GC(FID) is 11.0% - 17.0%. Consequently gas chromatography(GC-NPD, GC-FID) and high performance liquid chromatography(EPA TO-11) using 2,4-DNPH coated sampler for formaldehyde measurement turned out to be suitable to measure personal formaldehyde exposure at workplaces.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.799-804
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• 1994

A 0.625% dispersion of the pretreated konjac (Amorphophallus konjac) flour was treated with 3 volumes of ethanol and the precipitate was dried at room temperature to produce purified glucomannan in 67.2% yield. Konjac glucomannan was analyzed for proximate composition and the contents of total dietary fiber and minerals. TLC analysis with a mobile phase of isopropanol : $H_2O$(4 : 1, v/v) revealed the presence of mannose and glucose as component sugars. The molecular mass of konjac glucomannan was in the range between 240 and 370 kDa as determined by HPLC with a Protein Pak 300SW column. Water holding capacity of konjac glucomannan was greater than those of most other gums except guar and xanthan gums. Konjac glucomannan accelerated foam formation of bovine serum albumin. As the concentration of konjac glucomannan increased up to 2%, maximum viscosity increased drastically, whereas the swelling time at maximum viscosity decreased. When swelling temperature increased, maximum viscosity and the swelling time at maximum viscosity decreased simultaneously.

• Journal of the Korean Applied Science and Technology
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• v.10 no.2
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• pp.11-18
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• 1993

Contents of vitamin $D_3$ and 25-OH-vitamin $D_3$ in marine animal products(20 species) were determined by HPLC. The isomers of vitamin D, $D_2$ and $D_3$, were not clearly separated on a reversed phase, ${\mu}$ Bonda Pak, with 20% methanol-acetonitrile, and on a normal phase, Zorbax SIL. with 0.4% isopropanol-hexane, but 25-OH-vitamin $D_2$ and-$D_3$ were separated on either ${\mu}$ Bonda Pak with 10% methanol-acetonitrile, or on Zorbax SIL with 2.2% isopropanol-hexane, respectively. Although levels of vitamin $D_3$ and 25-OH-vitamin $D_3$ varied remarkably according to species, their average value(fish : $l,l87{sim}36,007$ I.U/sample 100g, mussel : $58{\sim}1,706$ I.U/sample 100g, pickle: $1,208{\sim}79,358$ I.U/sample 100g) was greatly higher than that of meat($80{\sim}100$ I.U/sample 100g) and dairy products($400{\sim}800$ I.U/sample 100g). Fatty tissues of fish and pickled fish intestines contained high level of vitamin $D_3$ and 25-OH-vitamin $D_3$, while the clam and mussel known to have various kinds of sterol including ${\Delta}^7$-sterol showed very low levels of vitamin $D_3$ and its derivative.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.41-44
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• 2015

We reported an outbreak of clinical strangles in thoroughbred horses due to capnophilic Streptococcus equi subsp equi in South Korea. On three different farms, we isolated 17 S equi subsp equi isolates from 29 horses with or without abscesses in their lymph nodes. Of the 17 isolates, two isolates from clinical cases grew well in aerobic conditions, whereas 7/7 isolates from clinical cases and 8/22 isolates from the nasal discharges of horses did not. The latter 15 isolates were capnophilic, oxygen-sensitive, and $CO_2$-requiring S equi subsp equi, which could not grow in aerobic conditions, but which grew well in a $CO_2$ incubator with 5% $CO_2$, in anaerobic conditions using a GasPak, and with reduced oxygen tension in a candle jar. This study is the first report of a strangles outbreak caused by capnophilic S equi subsp equi in South Korea.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.289-297
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• 2005

This study was conducted to develop the suitable nutrient solutions for variable Cruciferae leafy vegetables. l/2, 1 and 3/2 strength of nutrient solution recommended by National Horticultural Research Institute were supplied to plants in deep flow technique systems during 25 days. The growth of pak-choi and leaf mustard 'Asia curled' was highest in the 3/2 strength, and kaie 'TBC' in the 1 strength. Mean cation ratio of nutrient solution for pak-choi, leaf mustard and kale was K $49.5\%$, Ca $35.8\%$ and Mg $14.7\%$, which was obtained by calculating the uptake rates of water and nutrients. Suitable composition of the nutrient solution for Cruciferae leafy vegetables was N 14, P 3, K 6.8, Ca 4.8, $Mg 2m{\cdot}L^{-1}$. To examine the suitability of nutrient solution developed for Cruciferae vegetables (NSC), plants were grown 4 times from Sep. 2003 to Oct. 2004. When plants were grown in NSC, relative growth rate increased 1.1 to 2.5 times and vitamin C content 1.06 to 1.52 times. The proper plants to apply NSC for functional leaf vegetable production were leaf mustard 'Asia recurled', 'Redcurled' and 'Pamagreen', kale 'TBC', 'Portugal' and 'Hanchu collard', leaf broccoli 'New green', pak-choi, baby cabbage 'Red king' and 'Green king', flowering red chinese cabbage and Korean cabbage.

• Analytical Science and Technology
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• v.28 no.2
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• pp.125-131
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• 2015

A method was developed and fully validated for the determination of terbutaline, a β₂-receptor agonist, in human plasma. Plasma samples were prepared by solid-phase extraction with Sep-Pak silica, followed by high-performance liquid chromatography (HPLC). The terbutaline was pre-separated from the interfering components in plasma on a Luna C18 (2) column, and terbutaline and salbutamol as an internal standard were resolved and determined on a Luna Silica column. The two columns were connected by a switching valve equipped with silica pre-column. The pre-column was used to concentrate the terbutaline in the eluent from the C18 column before back-flushing onto the silica column with fluorescence detection at an excitation/emission wavelength of 276/306 nm. The method was shown to be specific by testing six different human plasma sources. Linearity was established for a concentration range of 0.4-20.0 ng/mL with a correlation coefficient of 0.9999. The lower limit of quantitation was 0.4 ng/mL with a precision of 10.1% as C.V.%.

• Analytical Science and Technology
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• v.13 no.1
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• pp.34-40
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• 2000

The optimum conditions for the half-life time and residual analysis of the iminoactadine triacetate fungicide on soils were investigated by using the gas chromatography. Iminoctadine triacetate(IOTA) was extracted from soils with 2.0 M-NaOH/methanol and chloroform. The extracted IOTA was derivatized to pyrimidine hexafluroacetylacetone by the acetylation and analyzed with GC/ECD after elimination of moisture and impurities on the Sep-Pak column. From the standard addition experiments with 0.1 and 1.0 ppm, the average recoveries were ranged from 83.8 to 93.2 % and the detection limit was 0.005 ppm. The half-life time of iminoctadine triacetate in the silty clay was 30 days in the laboratory and 19.5 days in the field test whereas it was 27 days and 17.5 days for each in case of silty loam.

• Journal of the Korean Data and Information Science Society
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• v.13 no.1
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• pp.47-53
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• 2002

A new redescending M-estimating function is introduced. The estimators by this new redescending function attain the same level of robustness as the existing redescending M-estimators, but have less asymptotic variances than others except few cases. We have focused on estimating a location parameter, but the method can be extended for a scale estimation.