• 한국전기전자재료학회논문지
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• 제19권10호
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• pp.953-959
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• 2006

Langmuir-Blodgett(LB)layers of Arachidic acid deposited by LB method were deposited onto slide glass as Y-type film. The structure of manufactured device is Au/arachidic acid/Al, the number of accumulated layers are $9{\sim}21$. Also, we then examined of the Metal-Insulator-Metal(MIM) device by means of I-V. The I-V characteristics of the device are measured from -3 to +3 V. The insulation property of a thin film is better as the distance between electrodes is larger.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.310-313
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• 2000

Polyaniline Emeraldine Base (PANI EB) polymerized by chemical oxidative polymerization was doped with Camphorsulfonic Acid(CSA). Polyaniline-Camphorsulfonic Acid Emeraldine Salt(PANI-CSA ES) solutions were solved in organic solvents and sonificated at the room temperature for different solvents in PANI-CSA ES solution and sonification time. PANI-CSA ES solutions was coated on PET films using bar coater. 1-Step oxidatively-polymerized Polyaniline-Camphorsulfonic Acid Emeraldine Salt(PANI-CSA ES) was solved in m-cresol:chloroform 1:1 co-solvents and their solution was bar-coated on PET film. The surface resistivities of these coated films were measured, The surface resistivity of PANI-CSA ES solution in m-cresol:chloroform 1:1 co-solvent system was 5${\times}$10$^2$$\Omega$/$\square$.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권4호
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• pp.318-322
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• 2004

Lactic acid is an environmentally benign organic acid that could be used as a raw material for biodegradable plastics if it can be inexpensively produced by fermentation. Two genes (ldhL and ldhD) encoding the L-(+) and D-(-) lactate dehydrogenases (L-LDH and D-LDH) were cloned from Lactobacillus sp., RKY2, which is a lactic acid hyper-producing bacterium isolated from Kimchi. Open reading frames of ldhL for and ldhD for the L and D-LDH genes were 962 and 998 bp, respectively. Both the L(+)- and D(-)-LDH proteins showed the highest degree of homology with the L- and D-lactate dehydrogenase genes of Lactobacillus plantarum. The conserved residues in the catalytic activity and substrate binding of both LDHs were identified in both enzymes.

• 한국응용과학기술학회지
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• 제20권2호
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• pp.148-153
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• 2003

Electron transfer through an Langmuir-Blodgett(LB) monolayer film sandwiched between metal electrodes. We used an eicosanoic acid material and the material was very famous as a thin film insulating material. Eicosanoic acid monolayer was deposited by Langmuir-Blodgett(LB) technique and a subphase was a $CdCl_2$ solution as a 2${\times}10^{-4}$ mol/L. Also we used a bottom electrode as an Al/$Al_2O_3$ and a top electrode as a Al and Ti/Al. Here, the $Al_2O_3$ on the bottom electrode was deposited by thermal evaporation method. The $Al_2O_3$ layer was acted on a tunneling barrier and insulating layer in tunnel diode. It was found that the proper transfer surface pressure for film deposition was 25 mN/m and the limiting area per molecule was about 24 ${\AA}^2$/molecule. When the positive and negative bias applied to the molecular device, the behavior shows that a tunnel switching characteristics. This result were analyzed regarding various mechanisms.

• 유기물자원화
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• 제18권3호
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• pp.68-76
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• 2010

비닐하우스에서 지렁이 분변토와 부식산의 혼합비율을 달리하여 토양에 시비하였을 때 열무의 생육특성 및 토양의 물리 화학성을 조사하였다. 10a 당 분변토 300kg(d.w.)에 고상 부식산 0, 5, 10, 15, 30, 50kg(a.i.)을 각각 혼합하여 시비하였으며, 관행퇴비 시비(600kg/10a)구와 무처리구를 두었다. 분변토가 시비된 모든 처리구에서 무처리구보다 엽수, 엽장, 엽폭, 엽의 생체중, 뿌리 길이, 직경, 뿌리의 생체중이 높게 나타났으며, 분변토+부식산이 시비된 처리구에서 열무 생육은 관행 시비의 경우와 대등하거나 그보다 상회하였다. 10a 당 분변토 300kg(d.w.)에 부식산 5kg을 혼합하였을 때 열무 엽의 생체중은 무처리의 1.79배, 뿌리의 생체중은 2.08배로 10kg 이상의 부식산을 혼합한 경우나 관행시비의 경우보다 현저하게 높았다. 분변토와 부식산을 시비한 토양에서 열무를 수확한 후에 토양의 이화학성 변화는 없는 것으로 나타났다.

• Current Research on Agriculture and Life Sciences
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• 제31권4호
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• pp.240-244
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• 2013

To evaluate utilization of persimmon peels as novel bio-materials, the general composition and antioxidant activities of Daebong persimmon vinegar (DPV), Daebong persimmon peel vinegar (DPPV) and commercial persimmon vinegar (CPV) were investigated. The pH of DPPV had slightly higher than that of other vinegars. The titratable acidities of vinegars were 3.24% (DPV), 2.77% (DPPV) and 7.78% (CPV), respectively. The reducing sugar contents showed that DPV had slightly higher than that of other vinegars. The browning degree of DPV was lower than CPV in contrast to the turbidity. The results of Hunter's color value have showed that overall values of CPV had significantly higher than DPPV and DPV. The total phenolic contents of DPV and CPV were 19.49 and 17.13 mg/100g GAE, respectively. The total flavonoid contents of DPPV (8.04 mg/100g CE) were two fold higher than that of DPV (3.85 mg/100g CE). The antioxidant activities, by DPPH and FRAP assays, of DPV showed stronger than those of other vinegars. Free sugars were mainly composed of fructose and glucose. Organic acids were presented in the order acetic acid, succinic acid, malic acid, tartaric acid, citric acid and oxalic acid. These results suggest that the Daebong persimmon peels could be utilized for vinegar production as a health-benefit material.

• Journal of Microbiology and Biotechnology
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• 제31권2호
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• pp.317-326
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• 2021

Vanillyl alcohol (VA), which is abundant in Vanilla bean, has strong antioxidant activity. However, the use of VA in the food and cosmetics industries is limited, due to its low solubility in emulsion or organic solvents. Meanwhile, medium chain fatty acids and medium chain monoglycerides have antibacterial activity. We synthesized butyric acid vanillyl ester (BAVE) or caprylic acid vanillyl ester (CAVE) from VA with tributyrin or tricaprylin through transesterification reaction using immobilized lipases. BAVE and CAVE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals in organic solvents. In addition, BAVE and CAVE decreased the production rate of conjugated diene and triene in the menhaden oil-in-water emulsion system. While BAVE showed no antibacterial activity, CAVE showed antibacterial activity against food spoilage bacteria, including Bacillus coagulans. In this study, the antibacterial activity of vanillyl ester with medium chain fatty acid was first revealed. Zeta potential measurements confirmed that BAVE and CAVE were inserted into B. coagulans membrane. In addition, the propidium iodide uptake assay and fluorescent microscopy showed that CAVE increased B. coagulans membrane permeability. Therefore, CAVE is expected to play an important role in the food and cosmetics industries as a bi-functional material with both antioxidant and antibacterial activities.

• 한국토양비료학회지
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• 제45권5호
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• pp.760-763
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• 2012

친환경 포도재배를 위하여 농가에서 용이하게 구입 및 제조가 가능한 유기농자재의 효과를 조사한 결과 본 연구에 사용한 농자재의 pH는 4.6이하였고, 아미노산액은 상대적으로 높은 비료성분을 함유하였다. 포도수확기 토양의 pH는 시험초기 (농자재 처리 전)와 비교할 때 감소하였고, EC와 유기물함량은 증가하였으며, 유효인산은 대조구 (관행처리)를 제외하고 증가하였다. 치환성 K는 은행잎추출액 처리구와 대조구, 치환성 Ca는 무처리구와 아미노산용액 처리구에서 감소하였고, 치환성 Mg는 모든 농자재 처리구에서 감소하였다. 포도 잎의 질소 (N) 함량은 chitosan과 아미노산액 처리구, P는 chitosan, 목초액 및 아미노산액 처리구, K는 chitosan과 아미노산액 처리구, Ca은 chitosan 처리구, Mg 함량은 아미노산액 처리구에서 가장 높았다. 포도 수량은 목초액 처리구와 대조구에서 $1,581{\sim}1,583kg\;10^{-1}$로 가장 많았고, 당도는 무처리구를 제외하고 같은 수준을 보였다.

• 한국식품저장유통학회지
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• 제31권2호
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• pp.235-244
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• 2024

A nonthermally sterilized raw apple vinegar was manufactured using an ultra-fine filtration process (0.2 ㎛ membrane filter) and its quality was comparable to commercially available vinegar products. First, using apple concentrate as a raw material, it was possible to produce non-thermal sterilized Using a two-stage fermentation process of alcohol and acetic acid fermentations, a non-thermally sterilized raw apple vinegar with pH 2.94 and an acidity of 6.20% was produced from an apple concentrate. The fermentation process increased the browning index significantly. However, the fundamental quality parameters of the non-thermal sterilized raw apple vinegar (A) with sterilized apple vinegar (B) did not differ significantly. The pH (2.92-2.95) of apple vinegar (A and B) was higher than that (pH 2.65-2.70) of commercial vinegar (C and D), and the total acidity, which is in the range of 6.20-6.21% and 6.53-6.90%, respectively, was higher in samples C and D than in samples A and B. However, four kinds of organic acids were detected in non-thermal sterilized raw apple vinegar (A), and its total organic acid content (6,245.00 mg%) was significantly higher than that of other samples (B, C, D) (p<0.05). In particular, malic acid content, as a main organic acid in apples, was very high in sample (A) (244.83 mg%) and sample (B) (210.21 mg%), compared to commercial products C (125.78 mg%) and D (86.90 mg%). The total polyphenol content and antioxidant activity of fermented apple vinegar (A, B) were more than twice as high as those of commercial products (C, D). Vinegar A had higher total polyphenol content than vinegar B. The above results suggest it is possible to manufacture and commercialize non-thermal sterilized raw apple vinegar with higher organic acid content and antioxidant properties using ultra-fine filtration.

• 한국토양환경학회지
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• 제2권1호
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• pp.45-50
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• 1997

산업구조의 변화와 더불어 많은 수의 휴ㆍ폐광산이 생김에 따라 그에 따른 환경오염 문제가 발생되고 있다. 특히 주로 황철광에서 생성된 폐수의 중금속 이온과 낮은 pH는 생태계를 파괴하는 피해를 입힌다. 따라서 산성광산폐수의 처리를 위한 많은 방법들이 연구되고 개발되고 있다. 본 연구에서는 산성광산 폐수의 생물학적 처리에서 사용되는 4가지 유기물원들의 중금속 처리 능력을 비교 분석하였다. 버섯퇴비, 참나무 퇴비, 슬러지 cake, 우분의 4가지 유기물원 중 산성 광산 폐수의 처리에 효과가 있는 것은 참나무 퇴비와 우분이었다. 참나무 퇴비는 주로 이온 교환이나 -OH와 -COO-등의 작용기에 의한 흡착에 의해서 중금속을 처리하였으며, 우분을 사용한 경우는 자체 내에 존재하고 있는 황산염환원균의 활성에 의해서 중금속을 처리하였다. 따라서 이 두 가지 유기물원을 혼합하여 사용한다면 상호 보완 작용에 의해 효과적인 처리 효율을 얻을 수 있을 것이다.