• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.5
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• pp.791-796
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• 2017

In this study, we investigated the influence of the fabrication process of stacked capacitors on the cell capacitance by using Load Lock (L/L) LPCVD system for dielectric thin film of DRAM capacitor. As a result, it was confirmed that the capacitance difference of about 3-4 fF is obtained by reducing the effective thickness of the oxide film by about $6{\AA}$ compared to the conventional non-L/L device. In addition, Cs was found to be about 3-6 fF lower than the calculated value, even though the measurement range of the thickness of the nitride film as an insulating film was in a normal management range. This is because the node poly FI CD is managed at the upper limit of the spec, resulting in a decrease in cell surface area, which indicates a Cs reduction of about 2fF. Therefore, it is necessary to control the thickness of insulating film and CD management within 10% of the spec center value in order to secure stable Cs.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.355-360
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• 2006

Antioxidative activity and physicochemical characteristics of heat-treated licorice extracted by ethyl-acetate (EtOAc) and ethyl-alcohol (EtOH) were evaluated at various treatment temperatures (110, 120, 130, 140, and $150^{\circ}C$), times (1, 2, 3, 4, and 5 hr), and moisture contents (10, 20, 30, 40, and 50%). Maximum extraction yields of EtOAc treated at $140^{\circ}C$, 2 hr, and 20% moisture content and EtOH extracts treated at $120^{\circ}C$, 2 hr, and 40% moisture content were 9.48 and 32.90%, whereas those of control were 3.74 and 14.60%, respectively. Highest total polyphenol content was obtained from 13.95 mg/g EtOH extract treated at $150^{\circ}C$, 3 hr, and 30% moisture content (control: 6.92 mg/g). Highest antioxidative activity $(IC_{50})$ was obtained from 0.32 g/L EtOAc treated at $140^{\circ}C$, 2 hr, and 20% moisture content (control: 0.57 g/L). Highest ascorbic acid equivalent antioxidant activity value of 2,112.61 mg ascorbic acid (AA) eq was obtained from EtOAc extract treated at $120^{\circ}C$, 2 hr, and 40% moisture content (control: 1,920.27 mg AA eq). Optimum heat treatment conditions were $130-140^{\circ}C$, 3 hr, and 30% moisture content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.689-695
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• 2007

Antioxidative activity and polyphenol contents of heated licorice in Korea extracted by ethyl.acetate (EtOAc) and ethyl.alcohol (EtOH) were evaluated at various heating temperatures (110, 120, 130, 140, and $150^{\circ}C$), times (1, 2, 3, 4, and 5 hr), and moisture contents (10, 20, 30, 40, and 50%). Maximum extraction yields of EtOAc extract was 10.9% at $130^{\circ}C$, 3 hr, and 50% moisture content and that of EtOH extract was 25.0% at $120^{\circ}C$, 2 hr, and 20% moisture content, whereas those of control were 0.8 and 15.8%, respectively. The highest total polyphenol content was 845.67 mg/100 g in EtOH extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 277.00 mg/100 g). The antioxidative activity ($IC_{50}$) was the highest value of 0.53 mg/mL in EtOAc extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 12.34 mg/mL). The highest ascorbic acid equivalent antioxidant activity value of 1,584 mg ascorbic acid (AA) eq was obtained from EtOAc extract at $120^{\circ}C$, 2hr, and 40% moisture content (control: 1,263 mg AA eq). Optimum heating conditions for the improvement of antioxidative activity of licorice in Korea was $120^{\circ}C$, 2 hr, and $20{\sim}40%$ moisture content.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1656-1662
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• 2012

This study was conducted to evaluate the vegetative value of sweet potato leaves and stalks by investigating their chemical composition and antioxidant activity. The major minerals were found to be Ca and K. The crude protein content of the leaves ranged from 15.57% in Geonpungmi to 20.34% in Yeonhwangmi, while that of stalks was between 3.71% in Yulmi and 5.97% in Sinchunmi. The total phenolics and flavonoids content of the leaves were about 3.0~4.0 times higher than those of stalks. The levels of polyphenols and flavonoids were high in Geonpungmi leaf and in Sinchunmi stalk. ABTS radical activities were high in Geonpungmi leaf (58.75 mg AA eq/g) and in Daeyumi stalk (14.95 mg AA eq/g). DPPH radical scavenging was high in Geonpungmi and Jeungmi leaves ($IC_{50}$, 0.11 mg/mL) and in Sinchunmi stalk ($IC_{50}$, 1.09 mg/mL).

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1529-1536
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• 2006

We cloned a gene of ompH(D:4) from pigs infected with P. multocida D:4 in Korea [16]. The gene is composed of 1,026 nucleotides coding 342 amino acids (aa) with a signal peptide of 20 aa (GenBank accession number AY603962). In this study, we analyzed the ability of the ompH(D:4) to induce protective immunity against a wild-type challenge in mice. To determine appropriate epitope(s) of the gene, one full and three different types of truncated genes of the ompH(D:4) were constructed by PCR using pET32a or pRSET B as vectors. They were named ompH(D:4)-F (1,026 bp [1-1026] encoding 342 aa), ompH(D:4)-t1 (693 bp [55-747] encoding 231 aa), ompH(D:4)-t2 (561 bp [187-747] encoding 187 aa), and ompH(D:4)-t3 (540 bp [487-1026] encoding 180 aa), respectively. The genes were successfully expressed in Escherichia coli BL21(DE3). Their gene products, polypeptides, OmpH(D:4)-F, -t1, -t2, and -t3, were purified individually using nickel-nitrilotriacetic acid (Ni-NTA) affinity column chromatography. Their $M_rs$ were determined to be 54.6, 29, 24, and 23.2 kDa, respectively, using SDS-PAGE. Antisera against the four kinds of polypeptides were generated in mice for protective immunity analyses. Some $50{\mu}g$ of the four kinds of polypeptides were individually provided intraperitoneally with mice (n=20) as immunogens. The titer of post-immunized antiserum revealed that it grew remarkably compared with pre-antiserum. The lethal dose of the wild-type pathogen was determined at $10{\mu}l$ of live P. multocida D:4 through direct intraperitoneal (IP) injection, into post-immune mice (n=5, three times). Some thirty days later, the lethal dose ($10{\mu}l$) of live pathogen was challenged into the immunized mouse groups [OmpH(D:4)-F, -t1, -t2, and -t3; n=20 each, two times] as well as positive and negative control groups. As compared within samples, the OmpH(D:4)-F-immunized groups showed lower immune ability than the OmpH(D:4)-t1, -t2, and -t3. The results show that the truncated-OmpH(D:4)-t1, -t2, and -t3 can be used for an effective vaccine candidate against swine atrophic rhinitis caused by pathogenic P. multocida (D:4) isolated in Korea.

• Journal of Animal Environmental Science
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• v.16 no.1
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• pp.51-60
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• 2010

This experiment was conducted to investigate the effects of concentrated pig slurry separated from membrane filter and by environment-friendly agro-materials mixtures on growth of lettuce in hydroponics. The swine waste treatment system having a ultra filtration and a reverse osmosis process was designed in this study. Filtration of pig slurry was necessary to prevent the hose clogging in hydroponics. Primary separation using ultra filter was followed by concentration by RO (Reverse Osmosis). The concentrated pig slurry (CS) was mixed by five different environment-friendly agro-materials mixtures. The chemical nutrient solution was the solution of National Horticulture Research Station for the growth of lettuce. The concentration of nutrient solution in hydroponics was adjusted a range of 1.5 mS/cm in EC. The concentrated pig slurry was low in phosphorus(P), suspended solid and heavy matal, but rich in potassium (K). The concentrated slurry was lowest in the growth characteristics of leaf lettuce. And also SPAD value in leaf was reduced in plot treated with concentrated slurry. But the growth of lettuce in the mixtures plot (CS+BM+AA, CS+BM+AA+SW) in hydroponics was significantly high compared to concentrated slurry. The fresh yield of lettuce was 78, 84% that of nutrient solution as 131.9, 142.2g in plot of CS+BM+AA and CS+BM+AA+SW, respectively. Our studies have shown that it is possible to produce organic culture using concentrated slurry and environment-friendly agro-materials mixture, although growth is slower than when using a conventional inorganic hydroponic solution.

• Korean Journal of Materials Research
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• v.8 no.1
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• pp.52-57
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• 1998

기존 산화물 투명전극에 비해 더욱 우수한 전기전도성을 가지는 다층구조의 투명전도막을 마그네트론 스퍼터링 장치를 이용해 제작하였다. 전기전도성을 극대화하기 위해 비저항이 가장 낮은 Ag 금속을 사용하고, 금속층의 상하부에 반사광을 재반사시키는 산화물층을 형성시킨 다층막구조를 이용하였다. Ag 금속막은 충분한 투과율과 전기전도성을 확보하기 위해 연속된 막을 이루기 시작하는 두께인 140$\AA$로 증착하였고, ITO 박막은 가시광 영역의 반사광을 재반사시키는 최적의 두께인 600$\AA$ 내외로 증차하였다. Ag 박막의 증착조건과 후속 ITO 박막증착공정은 Ag박막의 특성에 영향을 미치므로 다층막의 전기적, 광학적 특성은 이들 증착 조건에 민감한 영향을 받음을 확인하였다. 상온에서 Ag박막을 형성하고 ITO박막은 7mTorr의 낮은 압력에서 증착하여 제작한 투명전도막은 SVGA 급의 STN-LCD용 투명전극으로 사용 가능한 4Ω/ㅁ 이하의 낮은 면저항과 빛의 파장이 550nm일 때 85%이상의 투과도를 나타내었다.

• Journal of Sensor Science and Technology
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• v.4 no.1
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• pp.9-14
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• 1995

To fabricate low field magnetic sensors using magnetoresistance(MR) effects, we deposited thin layers of $600{\AA}$ in thickness of Ni-Co(0.7Ni-0.3Co) alloy on slide glasses. In the layers we ordered 4 arms of the fullbridge sensors in the shape of grid structure to be inclined at an angle of $45^{\circ}$ to main axis and made the areal rate increase to 67%. While the response characteristics of the fabricated sensors had good linearity in the magnetic field of ${\pm}0.5mT$ ranges, the white noise was 0.2 nV and the voltage sensitivity was 7.6 $nV/{\mu}T$.

• Journal of the Korean Chemical Society
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• v.62 no.6
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• pp.427-432
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• 2018

The reaction of [$[Ni(L)]Cl_2{\cdot}2H_2O$ (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[$14,4,0^{1.18},0^{7.12}$]docosane) with 1,1-cyclohexanediacetic acid ($H_2cda$) yields mononuclear nickel(II) complex, [$Ni(L)(Hcda^-)_2$] (1). This complex has been characterized by X-ray crystallography, electronic absorption, cyclic voltammetry and thermogravimetric analyzer. The crystal structure of 1 exhibits a distorted octahedral geometry with four nitrogen atoms of the macrocycle and two 1,1-cyclohexanediacetate ligands. It crystallizes in the triclinic system P-1 with a = 11.3918(7), b = 12.6196(8), $c=12.8700(8){\AA}$, $V=1579.9(2){\AA}^3$, Z = 2. Electronic spectrum of 1 also reveals a high-spin octahedral environment. Cyclic voltammetry of 1 undergoes one wave of a one-electron transfer corresponding to $Ni^{II}/Ni^{III}$ process. TGA curve for 1 shows three-step weight loss. The electronic spectra, electrochemical and TGA behavior of the complex are significantly affected by the nature of the axial $Hcda^-$ ligand.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.609-617
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• 1998

A microorganism capable of producing high level of extracellular cyclodextrin glucanotransferase(EC 2.4.1.19 ; CGTase) was isolated from Kimchi. 2-O-$\alpha$-D-glucopyranosyl L-ascorbic acid(AA-2G) was synthesized by transglycosylation reaction of CGTase using starch as a donor and L-ascorbic acid as an acceptor. The isolated strain S-6 was identified as Bacillus sp. S-6. The maximal CGTase production was observed in a medium containing 0.5% soluble starch, 1% yeast extract, 1% NaCO3, 0.1% K2HPO4, and 0.02% MgSO4 with initial pH 8.0. The strain was cultured at 37$^{\circ}C$ for 40 hr with reciprocal shaking. Using the culture supernatant as crude enzyme, the optimal pH and temperature of the CGTase activity of this strain were 7.0 and 4$0^{\circ}C$. In the effects of pH and temperature on the stability of the enzyme, the enzyme was stable in the range of pH 6.0~10.0 and up to 45$^{\circ}C$, respectively.