• Preventive Nutrition and Food Science
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• 제4권1호
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• pp.79-83
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• 1999

A potentiometric biosensor employing a CO3-2 ion-selective electrode(ISE) and malic enzyme immobilization in al flow injection analysis (FIA) system was constructed. Analytical parameters were optimized for L-malate determination . The CO3-2 -ISE-FIA system was composed of a pump, an injector, a malic enzyme (EC1.1.1.40) reactor, a CO3-2 ion-selective electrode, a pH/mV meter and a recorder. Cofactor NADP was also injected with substrate for theenzyme reaction into the system. Optimized analytical parameters for L-malate determination in the CO3-2 ISE-FIA system were as follows ; flow rate, 14.5ml/hr ; sample injection volume, 100ul; enzyme loading in the reactor, 20 units ; length of the enzyme reactor , 7 cm ; tubing length form the enzyme reactor to the detector as a geometric factor in FIA, 15 cm . The response time for measuring the entire L-malate concentration range (10-2 ~10-5 mol/L ; 4 injections )was <15minutes . In this CO3-2 -ISE-FIA system, the potential differences due to th eformation of CO3-2 by the reaction of malic enzyme on L-malate were correlated to L-malate concentration in the range of 10-2 ~10-5mol/L ; the detection limit was 10-5 mol/L. This potentionmetric CO3-2 ISE--FIA system was found to be useful for L-malate measurement.

• 한국식품조리과학회지
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• 제21권4호
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• pp.466-474
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• 2005

This study aimed to determine the microbiological quality obtained by adding green tea extracts to prepare cook-chill foods. For this study, chicken meat salad was blended with green tea extracts at concentrations of 0, 2 and $3\%$ and prepared for a cook-chill system. The microbiological effects of green tea extracts were assessed during the production process by measuring process time, temperature, pH and Aw and by determining total plate counts and coliforms. The effects of green tea extracts on total plate counts and coliforms were observed during cold storage at $3^{\circ}C$ for five days. Green tea extracts improved the microbiological quality and showed antibacterial properties when added to chicken meat salad prepared in a cook-chill production system. The use of green tea extracts should be further explored as a means of enhancing freshness and quality in cook-chill foods.

• 한국물환경학회지
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• 제20권5호
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• pp.520-524
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• 2004

As a feasibility study for the application of carbon nanotubes to the treatment of environmental pollutants, the adsorption characteristics of humic acid on carbon nanotubes has been investigated. The dispersion features of carbon nanotubes in aquatic environment were investigated by measuring the variation of their electrokinetic potentials with pH, and the effects of some dispersants on their dispersion features were also examined. Under the experimental conditions, humic acid was observed to mostly adsorb on nanotubes within a few minutes and reach the equilibrium state within about one hour. The adsorption features of humic acid on nanotubes were found to follow the Freundlich model better than the Langmuir Model. Humic acid adsorbed on carbon nanotubes endothermically and the change of enthalpy in adsorption reaction was estimated to be ca. 18.37kJ/mol at standard state. The entropic change in adsorption reaction for humic acid was ca. 0.0503kJ/mol at standard state and the activation energy for adsorption was also estimated based on the change of rate constants with temperature. FT-IR investigations showed that the functional groups such as alcohol, ester, and aromatics existing in the chemical structure of humic acid might work as the bridge in its adsorption on nanotubes.

• 한국물환경학회지
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• 제28권3호
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• pp.394-400
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• 2012

We drew the stage-discharge relations of Byeokgye Stream, located in Yangpyeong-gun, Gyeonggi-do, and analysed the correlation between items of water pollutants by measuring the flow rate and water pollutants thirty-four times from April 2010 to December 2010. The results showed that it tended to be low water season from April to June and from October and December, while tending to be water season from July to September. The average flow rate was $2.137\;m^3/sec:\;0.464\;m^3/sec$ in low water season and $13.970\;m^3/sec$ in high water season. The stage-discharge curve thereon was $Q=40.107{\times}(h-1.200)^{2.877}$. As to the correlations, the correlation between the water temperature and COD was 0.58, and the correlations of SS with BOD and COD were 0.46 and 0.40 respectively. The correlation between SS and T-P was 0.73, showing higher than other items.

• 한국작물학회지
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• 제41권5호
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• pp.563-568
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• 1996

담배 생육단계별 RNA, protease 활성도와 단백질 패턴의 변화를 파악하여 노화가 진행되는 과정에서 생리 ㆍ생화학적인 변화의 기초자료를 얻고자 본 실험을 수행하였으며 결과는 다음과 같다. 가용성 단백질 함량은 출엽 후 15일까지 증가하여 출엽 후 35일까지 일정하게 유지하였다. 총 RNA 함량은 출엽 후 15일에 가장 높았으며 출엽후 30일까지 급격한 감소를 보였다. Protease 활성 변화는 중성 protease (pH 7.8)가 활성이 높았으며 노화말기인 출엽 후 50일부터 갑자기 증가하였다. 전기영동 패턴은 큰 변화가 없었으나 61.0kd의 polypeptide은 출엽 후 35일부터 생성되어 노화말기까지 증가하였다.

• 한국염색가공학회지
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• 제23권1호
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• pp.43-50
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• 2011

Electrically conductive yarn coated with silver particles are widely used to make smart wear but recent studies on smart fabrics are focused on measuring method of electrical characteristics and improving technologies of its electric properties. Also durability of conductive yarn with environmental change was also important work to make smart fabric. We compared resistance changes of silver coated conductive yarns under various physical and chemical conditions such as repeated strain, heat exposure and pH for basic informations on smart wear manufacturing process. And we deduct that repeated strain among the physical conditions was most effective factors on yarn resistance change and the low resistance change was observed with increasing the number of filaments in identical yarn fineness.

• 한국식생활문화학회지
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• 제30권4호
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• pp.457-462
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• 2015

The goal of this study is to show that the investigate is preference of beetroot cookie is preferred by consumers and can help to replace calcium, which is depleted because of the stress. As the amount of beetroot powder is increased, pH value, spread factors, loss and leaving rates, and texture properties of cookies were decreased. As a result of the measuring of colorimetric characteristics, the values of "L", "a", "b" were all decreased as the amount of beetroot powder was increased. The cookies containing 30% of beetroot powder was estimated as the most suitable to eat because of the flavor, color, and taste of the beetroot. But cookies having 20% of beetroot powder were estimated as the best to eat because of the texture, sticking power, hardness, and general preference. According to the results, the cookies containing 20% of beetroot powder were selected as the most suitable cookies to eat.

• 생명과학회지
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• 제20권6호
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• pp.960-963
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• 2010

왕겨를 증류하여 생성된 왕겨초 증류액을 이용하여 접촉성 피부염에 어떤 영향이 있는지를 검토하였다. 왕겨초 증류액(2%)에 자소옆을 첨가한 샘플은 dinitrochlorobenzene에 의해 유발된 접촉성 피부염 질환 동물모델에서 피부상피조직의 비후정도를 약 20%정도의 수준으로 완화시키며, 이는 면역조직화학적인 방법으로 확인하였다. 이 결과로, 왕겨초 증류액은 아토피 완화 효과를 가지므로 이들의 적합한 조건을 확립한다면 향장소재 또는 이의 조성물로 유용하게 이용될 수 있다고 판단된다.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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• pp.45-49
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• 1999

Plant cell culture is emerging to express bioactive foreign proteins because it has several advantages in that it is safe, economical, genetically stable and eukaryotic expression system comparing with other expression systems. However several limitations such as slow growth rate, low expression level and lack of well established down stream process need to be answered. As a preliminary approach to produce the immunologically interested molecules through the plant cell culture, we tested if granulocyte-macrophage colony stimulating factors (GM-CSFs) from both murine (mGM-CSF) and human (hGM-CSF) are produced as a biologically active form through plant cell culture. The murine and human GM-CSF genes were cloned into the plant expression vector, pBI121, and Ti-plasmid mediated transformation of tobacco leaves was conducted using Agrobacterium tumefaciens harboring both recombinant GM-CSF (rGM-CSF) genes. Cell suspension culture was established from the leaf-derived calli of transgenic tobacco plant. Northern blot analysis indicated the expression of the introduced mGM-CSF gene in both transgenic plant and cell suspension cultures. In addition, the biological activities of both murine and human GM-CSF from plant cell culture were confirmed by measuring the proliferation of the GM-CSF dependent FDC-PI and TF-1 cells, respectively.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.35.1-35.1
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• 2009

Vertically aligned zinc oxide (ZnO) nanorods (NRs) with different surface morphology were grown by metal organic chemical vapor deposition (MOCVD) on sapphire substrate. The films thus prepared were characterized by measuring X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) studies. To study the effect of surface morphology on wettability, the contact angle (CA) of water was measured. It was demonstrated that the CA of the deposited ZnO NRs varied between $104^{\circ}$ and $135^{\circ}$ depending upon the surface morphology. Variable temperature photoluminescence (PL) have employed to probe the exciton recombination in high density and vertically aligned ZnO Nanorod arrays. The low-temperature PL characterizes the dominant near-band-edge excitonic emissions from such nanorod arrays.