• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.55-58
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• 2003

We fabricated the textured Ni substrate and evaluated the effects of processing variables on microstructural evolution and texture transformation. Ni-rods as an initial specimen were prepared by two different methods, i.e., powder metallurgy(P/M) and plasma arc melting(PAM) The texture of the substrate was characterized by pole-figure and surface condition was evaluated by atomic force microscopy. It was observed that the texture of substrate made by P/M did not significantly varied with annealing temperature of 800~120$0^{\circ}C$ and the full-width at half-maximums (FWHM) of both in-plane and out-of-plane were 9$^{\circ}$~10$^{\circ}$. On the other hand, the texture of substrate made by PAM was more dependent on the annealing temperature and the FWHMs of in-plane texture was 9$^{\circ}$~13$^{\circ}$ at the temperature range. In addition, twin texture, (221)＜221＞, was formed as the temperature increased further. The grain size of substrate made by P/M was smaller than that made by PAM and this difference was correlated to the microstructure of initial specimens.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.538-540
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• 2009

The SBN thin films were deposited at substrate temperature of 300[$^{\circ}C$] on Pt-coated electrode (Pt/Ti/$SiO_2$/Si(100)) using RF sputtering method. The grain and crystallinity of SBN thin films were increased with the increase of annealing temperature. The dielectric constant(150) of SBN thin film was obtained by annealing temperature above 750[$^{\circ}C$]. The voltage dependence of dielectric loss showed a value within 0.01 in voltage ranges of -5~+5[V]. The capacitance characteristics showed a stable value of about 0.7[${\mu}F/cm^2$].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.845-848
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• 2002

The study of photoconductor materials is demanded for development for flat-panel digital x-ray Imager. In this paper, We investigated the feasibility of application as x-ray image sensor using Cd(Zn)Te compound with high stopping power on high radiation. These Cd(Zn)Te samples were fabricated by vacuum thermal evaporation method to large area deposition and investigated I-V measurement as applied voltage. The experimental results show that the additional injection Zn in CdTe film reduced the leakage current, for the $Cd_{0.85}Zn_{0.15}Te$ detector, the net charge had the highest value as $144.58pC/cm^2$ at 30 V.

• Journal of Biosystems Engineering
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• v.34 no.1
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• pp.30-36
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• 2009

This study was performed to determine the effect of drying conditions on the germination properties of rapeseed after seeds were dried under different drying conditions: $40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$ in combination with 30%, 45%, or 60% relative humidity. As analytic results, drying conditions had significant effects (P-value < 0.001) and drying temperature was considered as the main factor on the germination properties of rapeseed. When drying temperature increased or relative humidity decreased, the vigor rate and germination rate decreased, the median germination time increased. The maximum values of vigor rate and germination rate were 90% and 95.44%, and their minimum values were 60.17 and 75%, respectively. To ensure the standard germination rate of 85%. The appropriate drying zone was determined and the drying temperature should be less than $51.0^{\circ}C$, $54.5^{\circ}C$ and $58.7^{\circ}C$ at 30%, 45% and 60% RH, respectively. The values for median germination time varied from 2 to 4 days. The predicted models of germination rate, vigor rate, and median germination time were determined.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.207-211
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• 1993

The CO substitution reactions in the complex, $Cp(S-C_5H_7)CrCO$ with $PR_3(PR_3=PMePh_2,\;P(OCH_3)_3,\;PMe_2Ph)$ were investigated spectrophotometrically at various temperatures. From the reaction rates, it was suggested that the CO substitution reaction takes place by first-order (dissociative) pathway. Activation parameters in decaline are ${\Delta}H^{\neq}\;=\;24.58\;kcal\;{\cdot}\;mol^{-1},\;{\Delta}S^{\neq}\;=\;3.05 cal\;{\cdot}\;mol^{-1}{\cdot}K^{-1}$. Unusually low value of ${\Delta}S^{\neq}$ suggests an ${\eta}^5-S\;{\to}\;{\eta}^5-U$ conversion of the pentadienyl ligand. This was confirmed by the extended-Huckel molecular orbital (EHMO) calculations, which revealed that the total energy Of $Cp(S-C_5H_7)CrCO$ is about 6.84 kcal/mol more stable than that of $Cp(U-C_5H_7)CrCO$ and the energy of $[Cp(U-C_5H_7)CrCO^{\neq}$ transition state is about 4.25 kcal/mol lower than that of $[Cp(S-C_5H_7)Cr]^{\neq}$ transition state.

• Diabetes and Metabolism Journal
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• v.42 no.6
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• pp.480-487
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• 2018

Background: This study aimed to evaluate the relationship between the frequency of self-monitoring of blood glucose (SMBG) and glycosylated hemoglobin (HbA1c) levels among Korean adolescents with type 1 diabetes mellitus (T1DM). Factors affecting the SMBG frequency were analyzed in order to improve their glycemic control. Methods: Sixty-one adolescents aged 13 to 18 years with T1DM were included from one tertiary center. Clinical and biochemical variables were recorded. Factors associated with SMBG frequency were assessed using structured self-reported questionnaires. Results: Average total daily SMBG frequency was $3.8{\pm}2.1$ and frequency during the school day was $1.3{\pm}1.2$. The mean HbA1c level was $8.6%{\pm}1.4%$. As the daily SMBG frequency increased, HbA1c levels declined (P=0.001). The adjusted odds of achieving the target HbA1c in participants who performed daily SMBG ${\geq}5$ significantly increased 9.87 folds (95% confidence interval [CI], 1.58 to 61.70) compared with those performed SMBG four times a day. In the subjects whose SMBG frequency <1/day during the school day, an 80% reduction in the adjusted odds ratio 0.2 (95% CI, 0.05 to 0.86) showed compared to the group with performing two SMBG measurements in the school setting. The number of SMBG testing performed at school was significantly high for individuals assisted by their friends (P=0.031) and for those who did SMBG in the classrooms (P=0.039). Conclusion: Higher SMBG frequency was significantly associated with lower HbA1c in Korean adolescents with T1DM. It would be necessary to establish the school environments that can facilitate adequate glycemic control, including frequent SMBG.

• Journal of Life Science
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• v.29 no.11
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• pp.1173-1178
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• 2019

The purpose of this study was to isolate an agar-degrading marine bacterium and characterize its agarase. Bacterium BK-1, from Gwanganri Beach at Busan, Korea, was isolated on Marine 2216 agar medium and identified as Agarivorans sp. BK-1 by 16S rRNA gene sequencing. The extracellular agarase, characterized after dialysis of culture broth, showed maximum activity at pH 6.0 and $50^{\circ}C$ in 20 mM Tris-HCl buffer. Relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 67, 93, 97, 100, 58, and 52%, respectively. Relative activities at pH 5, 6, 7, and 8 were 59, 100, 95, and 91%, respectively. More than 90% of the activity remained after a 2 hr exposure to 20, 30, or $40^{\circ}C$; about 60% of the activity remained after a 2 hr exposure to $50^{\circ}C$. Almost all activity was lost after exposure to 60 or $70^{\circ}C$ for 30 min. Zymography revealed three agarases with molecular weights of 110, 90, and 55 kDa. Agarose was degraded to neoagarobiose (46.8%), neoagarotetraose (39.7%), and neoagarohexaose (13.5%), confirming the agarase of Agarivorans sp. BK-1 as a ${\beta}$-agarase. The neoagarooligosaccharides generated by this agarase could be used for moisturizing, bacterial growth inhibition, skin whitening, food treatments, cosmetics, and delaying starch degradation.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.4
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• pp.537-543
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• 1999

Whole horse beans (Vicia faba cv. Alfred) (WHB) were pressure toasted at different temperatures of 100, 118 and $136^{\circ}C$ for 3, 7, 15 and 30 minutes in order to determine an optimal heating conditions to increase bypass starch (BPSt) as glucose source which is usually limiting nutrient in highly producing dairy cows in the Netherlands. Starch (St) Ruminal Degradative Kinetics and Fermentation Characteristics of (SRDC) of WHB were determined using in sacco technique in 4 lactating dairy cows fed 47% hay and 53% concentrate according to Dutch dairy cow requirements. Measured characteristics of St were soluble fraction (S), potentially degradable fraction (D) and rate of degradation (Kd) of insoluble but degradable fraction. Based on measured characteristics, percentage bypass starch (BPSt) was calculated according to the Dutch new feed evaluation system: the DVE/OEB system. Pressure toasting temperatures significantly affected starch gelatinization (p<0.01). Degradability of Starch in the rumen was highly reduced by pressure toasting (p<0.01). S varied from 58.2% in the raw WHB (RWHB as a control) to 19.6% in $136^{\circ}C/15min$. S was reduced rapidly with increasing time and temperature (p<0.01). D varied from 41.8% in RWHB to 80.5% in $136^{\circ}C/15min$. D fraction was enormously increased with increasing time and temperature (p<0.01). Kd varied from 4.9%h in RWHB to 3.4%/h in $136^{\circ}C/15min$. All these effects resulted in increasing %BPSt from 29.0% in RWHB to 53.1% in $136^{\circ}C/15min$. Therefore BPSt increased from 93.5 g/kg in RWHB to 173.5 g/kg in $136^{\circ}C/15min$. The effects of pressure toasting on %BPSt and BPSt seemed to be linear up to the highest values tested. Therefore no optimal pressure toasting conditions could be determined at this stage. But among 10 treatments, The treatment of $136^{\circ}C/15min$was the best with the highest BPSt content. It was concluded that pressure toasting was effective in shifting starch degradation from rumen to small intestine to increase bypass starch.

• Journal of Microbiology and Biotechnology
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• v.24 no.4
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• pp.545-555
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• 2014

It has been previously demonstrated that laccases exhibit great potential for use in several industrial and environmental applications. In this paper, two laccase isoenzyme genes, lccB and lccC, were cloned and expressed in Pichia pastoris GS115. The sequence analysis indicated that the lccB and lccC genes consisted of 1,563 and 1,584 bp, and their open reading frames encoded 520 and 527 amino acids, respectively. They had 72.7% degree of identity in nucleotides and 86.7% in amino acids. The expression levels of LccB and LccC were up to 32,479 and 34,231 U/l, respectively. The recombinant laccases were purified by ultrafiltration and $(NH_4)_2SO_4$ precipitation, showing a single band on SDS-PAGE, which had a molecular mass of 58 kDa. The optimal pH and temperature for LccB were 2.0 and $55^{\circ}C$ with 2,2'-azinobis-[ 3-ethylbenzthiazolinesulfonic acid (ABTS) as a substrate, whereas LccC exhibited optimal pH and temperature at 3.0 and $60^{\circ}C$. The apparent kinetic parameters of LccB were 0.43 mM for ABTS with a $V_{max}$ value of 51.28 U/mg, and the Km and $V_{max}$ values for LccC were 0.29 mM and 62.89 U/mg. The recombinant laccases were able to decolorize five types of dyes. Acid Violet 43 (100 g/ml) was completely decolorized by LccB or LccC (2 U/ml), and the decolorization of Reactive Blue KN-R (100 g/ml) was 91.6% by LccC (2 U/ml). Thus, the study characterizes useful laccase isoenzymes from T. versicolor that have the capability of being incorporated into the treatment of similar azo and anthraquinone dyes from dyeing industries.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.220-231
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• 2002

The fish fauna and Community were surveyed from April 2000 to September 2001 at 23 stations in the nam river, the first tributary located to the lower reach of the Nakdong River system. During the study period, 39 species belonging to 29 genera and 11 families were collected. Of which 14 species are endemic species or subspecies in Korea. Introduced species from other river system, O. bidens had not been collected at all after the report of Yang (1973) but many individuals were captured at main stream and tributary in this survey. Introduced species from abroad M. salmoides increased at most of stations. Dominant species in main stream were Z. platypus, O. bidens and H. labeo. On the contrary, Z. temmincki, Z. platypus and S. gracilis majimae dominated the tributaries. Diversity indices of main stream and tributaries were 0,979 and 0.966 respectively. St. 3 of main stream and St.1 and 16 of tributaries had high diversity indices (1.05, 0.962, 0.956) and lower dominant indices (0.102, 0.369, 0.200). As a whole, dominant index was 0.160, diversity index 1.044 and evenness index 0.656. It indicated that the community structure of this river was stable and diverse relatively.