• Journal of Microbiology and Biotechnology
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• v.25 no.12
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• pp.2049-2057
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• 2015

Various salt concentrations (1.0%, 1.3%, 1.6%, 1.9%, and 2.1% labeled as sample A, B, C, D, and E, respectively) were investigated for microbial diversity, identification of Lactic Acid Bacteria (LAB) in salted kimchi cabbage, prepared under laboratory conditions. These samples were stored at 4°C for 5 weeks in proper aluminum-metalized pouch packaging with calcium hydroxide gas absorber. A culture-independent method known as polymerase chain reaction - denaturing gradient gel electrophoresis was carried out to identify LAB distributions among various salt concentration samples that had identified 2 Weissella (W. confusa and W. soli), 1 Lactobacillus (Lb. sakei), and 3 Leuconostoc (Lc. mesenteroides, Lc. lactis, and Lc. gelidum) in the overall kimchi samples. The pH, titratable acidity, viable cell counts, and coliform counts were not affected by salt variations. In order to assess sensory acceptance, the conducted sensory evaluation using a 9-point hedonic scale had revealed that samples with 1.3% salt concentration (lower than the manufacturer's regular salt concentration) was more preferred, indicating that the use of 1.3% salt concentration was acceptable in normal kimchi fermentation for its quality and safety. Despite similarities in pH, titratable acidity, viable cell counts, coliform counts, and LAB distributions among the various salt concentrations of kimchi samples, the sample with 1.3% salt concentration was shown to be the most preferred, indicating that this salt concentration was suitable in kimchi production in order to reduce salt intake through kimchi consumptions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.6
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• pp.449-453
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• 2003

Ferroelectric YMnO$_3$ thin films were etched with Ar/Cl$_2$ and CF$_4$/Cl$_2$ inductively coupled plasma (ICP). The maximum etch rate of YMnO$_3$ thin film was 300 $\AA$/min at a Ar/Cl$_2$ gas mixing ratio of 2/8, a RF power of 800 W, a DE bias of 200 V, a chamber pressure of 15 mTorr, and a substrate temperature of 30 $^{\circ}C$. From the X-ray photoelectron spectroscopy (XPS) analysis, yttrium etched by chemical reactions with Cl radicals assisted by Ar ion bombardments in Ar/Cl$_2$ plasma. In CF$_4$/Cl$_2$ plasma, yttrium are remained on the etched surface of YMnO$_3$ and formed of nonvolatile YF$_{x}$ compounds manganese etched effectively by chemical reactions with Cl and F radicals. From the X-ray diffraction (XRD) analysis, the (0004) diffraction peak intensity of the YMnO$_3$ thin film etched in Ar/Cl$_2$ plasma shows lower value than that in CF$_4$/Cl$_2$ plasma. It indicates that the crystallinty of YMnO$_3$ thin film is more easily damaged by the Ar ion bombardment than the changes of stoichiometry due to nonvolatile etch by-products.s.

• Progress in Superconductivity and Cryogenics
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• v.9 no.2
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• pp.23-26
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• 2007

The influence of water partial pressure in Metal-organic Deposition (MOD) method was investigated on the texture and the morphology of $YBa_2Cu_3O_{7-x}$ (YBCO) films grown on the buffered metal tapes. The water partial pressure was varied from 4.2% up to 10.0% with the other process variables, such as annealing temperature and oxygen partial pressure, kept constant. In this work, the fluorine-free Y & Cu precursor solution added with Sm was synthesized and coated by the continuous slot-die coating & calcination step. The next annealing step of the YBCO films was done by the reel-to-reel method with the gas flowed vertically down. From the x-ray diffraction analysis, the un-reacted phase like $BaF_2$ peak was found at the water partial pressure of 4.2%, but $BaF_2$ peak intensity is much reduced as the water partial pressure is increased. However, the higher water partial pressure of about 10% in this experiment leads to the poor crystallinity of YBCO films. The morphologies of the YBCO films were not different from each other when the water partial pressure was varied in this work. The maximum critical current density of 3.8MA/$cm^2$ was obtained at the water partial pressure of 6.2% with the annealing temperature of 780$^{\circ}C$ and oxygen partial pressure of 500ppm.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.1073-1079
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• 2010

Forty-eight ((Duroc${\times}$Yorkshire)${\times}$Landrace) pigs with an average initial body weight (BW) of $48.47{\pm}1.13\;kg$ were used in a 12-week growth trial to investigate the influence of Anion (silicate) supplementation on growth performance, nutrient digestibility, meat quality and fecal noxious gas content in growing-finishing pigs. Pigs were allotted into three dietary treatments in a randomized complete block design according to sex and initial BW. Each dietary treatment consisted of four replications with four pigs per pen. Dietary treatments included: i) CON (basal diet), ii) HCI (basal diet+3 g/kg Anion), iii) HCII (basal diet+6 g/kg Anion). No significant difference (p>0.05) was detected for average daily gain (ADG), average daily feed intake (ADFI) and gain/feed ratio (G/F) throughout the experiment, although dietary supplementation of Anion numerically increased these characteristics compared with CON. The dietary HCI group significantly (p<0.05) increased the coefficient of total tract apparent digestibility (CTTAD) of dry matter (DM), nitrogen (N) and energy compared with the CON group (p<0.05). No significant difference was observed in meat quality except that meat firmness was linearly (p<0.05) increased by the Anion supplementation, while an increased tendency in meat color and a decreased tendency in 2-thiobarbituric acid reactive substances (TBARS) was also observed (p<0.10). Anion supplementation linearly (p<0.05) decreased the fecal $NH_3$ compared with the CON group. However, dietary Anion supplementation at 3 g/kg decreased the $H_2S$ concentration compared with CON, while no significant difference was detected in the HCII group, although the $H_2S$ emission was numerically decreased compared with CON. In conclusion, supplementation of the diet with 3 g/kg Anion was found to exert a beneficial effect on nutrient digestibility and meat quality of growing-finishing pigs, and concomitantly decreased the noxious gas emission without negative effect on growth performance.

• KSBB Journal
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• v.11 no.6
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• pp.654-662
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• 1996

Bacterial strains which degrade crude oil were isolated by liquid culture from oil-spilled soil, and four isolates were selected among them. The strain Hl7-1 was finally selected after testing emulsifying activity and oil conversion rate. The strain Hl7-1 was identified as a Nocardia sp. based on the test for morphological, biochemical and physiological characteristics. It appears to be highly specialized for growth on crude oil in minimal salts medium since it showed preference for oil or degradation products as substrates for growth. It was found that it could grow on at least fifteen different hydrocarbons. The optimum cultural and environmental conditions were seeked. Cell growth and emulsification activity as a function of time were also determined. Crude oil degradation and the reduction of product peak was identified by the analysis of remnant oil by gas chromatography after 3 days of cultivation. Approximately 83% of oil were converted into a form no longer extractable by organic solvents.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.110.1-110.1
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• 2010

A bench scale slurry bubble column reactor (SBCR) with active-Fe based catalyst was developed for the Fischer-Tropsch synthesis (FTS) reaction. Considering the highly exothermic reaction heat generated in the bench scale SBCR, an effective cooling system was devised consisting of a U-type dip tube submerged in the reactor. Also, the physical and chemical properties of the catalyst were controlled so as to achieve high activity for the CO conversion and liquid oil ($C_{5+}$) production. Firstly, the FTS performance of the FeCuK/$SiO_2$ catalyst in the SBCR under reaction conditions of $265^{\circ}C$, 2.5 MPa, and $H_2/CO=1$ was investigated. The CO conversion and liquid oil ($C_{5+}$) productivity in the reaction were 88.6% and 0.226 $g/g_{cat}-h$, respectively, corresponding to a liquid oil ($C_{5+}$) production rate of 0.03 bbl/day. To investigate the FTS reaction behavior in the bench scale SBCR, the effects of the space velocity and superficial velocity of the synthesis gas and reaction temperature were also studied. The liquid oil production rate increased upto 0.057 bbl/day with increasing space velocity from 2.61 to 3.92 $SL/h-g_{Fe}$ and it was confirmed that the SBCR bench system developed in this research precisely simulated the FTS reaction behavior reported in the small scale slurry reactor.

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.21-29
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• 1996

Levels of total, neutral and polar lipids from the seeds of eight species of the Cucurbitaceae f Cucurbita moschata, Lufa cylindrica, Citrullus vulgari, Cucumis melo var. makuwa, Cucumis satvus, Lag leucantha. Trichosanthes kirilowii and Momordica charantia, were determinded, and their fatty compositions were also analyzed by gas-liquid chromatography. The results were summarized as foll. Lipid contents of the seeds range from 21.9 to 50.7%, which contained 98% up of neutral lipi the fatty acid compositon of ottal lipids from the seeds of Cucurbita moschata, Lufa cylindrica, Ci vulgari, Cucumis melo var. makuwa, Cucumis sativus and Lagenaria leucantha, linoleic acid is the mos dominant component(56.8${\sim}$84.0%) followed by oleic acid(5.7${\sim}$22.2%) and palmitic acid(6.1${\sim}$1) with a trace amount of ${\alpha}-linolenic$ acid(below 0.6%). On the contrary, the seed oils of Tricho kirilowii and Momordica charantia are characterized by presence of considerable amounts of con trienoic acid such as punicic acid($_{9c.11t.13c-}C_{18:3}$) and ${\alpha}-eleostearic$ acid($_{9c.11t.13c-}C_{18:3}$). For example total lipids of T. kirilowii seeds were mainly composed of linoleic acid(40.5%) and punicic acid(3) in the fatty acid composition, while those of M. charantia seeds predominantly comprised ${\alpha}-eleos$ acid as a main component(66.9%), accompanied by oleic acid(11.7%) and linoleic acid(10.4%). oil ${\beta}-eleostearic$ acid($_{9t.11t.13c-}C_{18:3}$) was checked as a trace. Fatty acid profiles of neutral lipids close resemblance to those of total lipids in all the seed oils, but are different from those of polar In particular, conjugate trienoic acids including punicic acid and ${\alpha}-eleostearic$ acid which are oc as the most abundant component in both neutral lipids of T. kirilowii and M. charantia seed oils, ar ent in a extremely small amount in both polar lipids. The fatty acid distribution in the polar lipid the samples except for T. kirilowii and M. charantia seed oils, showed a tendency of consid increased level of saturated fatty acids(25.0${\sim}$29.4%) compared with that in the neutral lipids(9.9%). The results obtained in this experiment suggest us that the seed oils of the Cucurbitaceae

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.162-162
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• 2014

최근 들어 wearable computing에 대한 수요가 증가하면서 flexible device에 대한 연구가 활발히 진행되고 있다. 하지만, flexible device를 구현하기 위해서는 기판의 damage를 줄이기 위한 저온공정, device life-time 향상을 위한 passivation, 와이어 본딩 등 다양한 문제들이 해결 되어야 한다. 이러한 문제들 중, polymer 기판과 금속간의 접착력을 향상시키기 위해서 많은 연구자들은 기판의 표면에 adhesive layer를 도포하거나 금속잉크의 solvent를 변화시키는 등의 연구를 진행해왔다. 종래의 연구는 기존 device를 대체 할 수 있을 정도의 생산성과 polymer 기판에 대한 열 적인 손상 이 문제가 되었다. 종래의 문제를 해결하기 위하여 저온공정, in-line system이 가능한 준 준 대기압 플라즈마를 사용하였다. 본 연구에서는 금속잉크를 Ink-jet으로 jetting하여 와이어 본딩 하는 과정에서 전도성 ink의 선폭을 유지시키고 접착력을 향상하기 위하여 준 대기압 플라즈마 공정을 이용하여 이러한 문제점을 해결하고자 하였다. Polymer 기판 표면에 roughness를 만들기 위해 대략 수백 nm 크기를 갖는 graphene flake를 spray coating하여 마스크로 사용하고 준 대기압 플라즈마를 이용하여 표면을 식각 함으로써 roughness를 형성시켰다. 준 대기압 플라즈마를 발생시키기 위해 double discharge system에서 6 slm/1.5 slm (He/O2) gas composition을 하부 전극에 흘려보내고 60 kHz, 5 kV 파워를 인가하였다. 동시에 상부 전극에는 30 kHz, 5 kV 파워를 인가하여 110초 동안 표면 식각 공정을 진행하였다. Graphene flake mask가 coating되어 있는 유연기판을 산소 플라즈마 처리 한 후 물에 3초 동안 세척하여 표면에 남아있는 graphene flake를 제거하고 6 slm/0.3 slm (He/SF6)의 유량으로 주파수와 파워 모두 동일 조건으로 110초 동안 표면 처리를 하였다. Figure 1은 표면 개질 과정과 graphene flake를 mask로 사용하여 얻은 roughness 결과를 SEM을 이용하여 관찰한 결과이다. 이와 같이 실험한 결과 ink와 기판간의 접촉면적을 늘려주고 접촉 각을 조절하여 Wenzel model 을 형성 할 수 있는 표면 roughness를 생성하였고 표면의 화학적 결합을 C-F group으로 치환하여 표면의 물과 접촉각 이 $47^{\circ}$에서 $130^{\circ}$로 증가하는 것을 확인하였다.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.526-534
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• 2019

Chlorella gloriosa (Chlorellaceae, Trebouxiophyceae) was isolated from seawater off the coast of the Dokdo Islands in Korea. An axenic culture was established using the streak-plate method on f/2 agar media supplemented with antibiotics, allowing identification of the isolate by morphological, molecular, and physiological analyses. The morphological characteristics observed by light and electron microscopy revealed typical morphologies of C. gloriosa species. The molecular phylogenetic inference drawn from the small-subunit 18S rRNA sequence verified that the microalgal strain belongs to C. gloriosa. Additionally, gas chromatography-mass spectrometry analysis showed that the isolate was rich in nutritionally important omega-3 and -6 polyunsaturated fatty acids and high-performance liquid chromatography analysis revealed that the high-value antioxidants lutein and violaxanthin were biosynthesized as accessory pigments by this microalga, with arabinose, galactose, and glucose as the major monosaccharides. Therefore, in this study, a Korean marine C. gloriosa species was discovered, characterized, and described, and subsequently added to the national culture collection.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.781-790
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• 2011

The effects of seedtime and maturity stage on nutritive value of five maize stover varieties, including conventional maize (Kexiangyu 11, CM), fodder maize (Huqing 1, FM), high oil maize (Gaoyou 115, HOM), sweet maize (Kexiangtianyu 1, SM) and waxy maize (Kexiangluoyu 1, WM), were examined based on chemical composition, in vitro gas production and in situ incubation techniques. Maize stover was sampled at d 17 and d 30 after tasseling, and designated as maturity stage 1 and stage 2, respectively. The average dry matter (DM) organic matter (OM), crude protein (CP) and fiber contents were the greatest for HOM, SM and FM, respectively. CM had the highest in vitro organic matter disappearance (IVOMD) and volatile fatty acid (VFA) concentration. The highest ammonia nitrogen ($NH_3$-N) concentration in the incubation solution, and effective degradability of DM ($ED_{DM}$) and neutral detergent fiber ($ED_{NDF}$) were observed in SM. Advanced maturity stage increased (p<0.05) DM content, $ED_{DM}$ and $ED_{NDF}$, but decreased (p<0.05) OM and CP contents, and decreased (p<0.05) b and a+b values, IVOMD and molar proportion of valerate in the incubation solution for maize stover. Maize sown in summer had greater (p<0.05) OM content, but lower DM, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) content compared with maize sown in spring. Maize sown in summer had greater (p<0.001) IVOMD, $NH_3$-N concentration in the incubation solution and $ED_{NDF}$, but lower (p<0.01) ratio of acetate to propionate compared to maize sown in spring. The interaction effect of variety${\times}$seedtime was observed running through almost all chemical composition, in vitro gas production parameters and in situ DM and NDF degradability. The overall results suggested that SM had the highest nutrient quality, and also indicated the possibility of selecting maize variety and seedtime for the utilization of maize stover in ruminants.